Data items in the EM_2D_CRYSTAL_ENTITY category record
the symmetry details of a 2D crystal assembly component.
Space-group number from International Tables for Crystallography,
Vol. A (1987).
Unit-cell angle gamma of the reported structure, in degrees.
Additional details describing this 2D crystal component
Unit-cell length a corresponding to the structure reported, in Angstroms.
Unit-cell length b corresponding to the structure reported, in Angstroms.
The 17 plane groups are classified as oblique, rectangular, square, and hexagonal.
To describe 2D crystals of biological molecules,
the plane groups are expanded to their equivalent noncentrosymmetric space groups.
The space group setting is chosen such that the 2D crystal plane
corresponds to the 'ab' plane of the space group.
.
Enumerated space group descriptions include the H-M plane group symbol
and plane group class.
The thickness of the crystal sample in the out-of-plane
direction.
The value of attribute entity_assembly_id in category em_2d_crystal_entity identifies
an assembly component with 2d crystal symmetry.
This data item is a pointer to attribute id in category em_entity_assembly in the
EM_ENTITY_ASSEMBLY category.
The value of attribute id in category em_2d_crystal_entity must uniquely identify
a set of the crystal parameters for this assembly component.
Data items in the EM_2D_CRYSTAL_SELECTION category record details
for the selection of 2D crystals.
Any additional details used for selecting 2d crystals.
negative monitor contrast facilitated particle picking
The value of attribute selection_id in category em_2d_crystal_selection identifies
the general set of selection conditions associated with specific
filament selection conditions described in this category.
The value of attribute selection_id in category em_2d_crystal_selection points to
the attribute id in category em_particle_selection in the EM_PARTICLE_SELECTION category.
Data items in the 3D_FITTING category
record details of the method of fitting atomic
coordinates from a PDB file into a 3d-em
volume map file
Example 1 - EMDB entry EM1078
<mmcif_em:em_3d_fittingCategory>
<mmcif_em:em_3d_fitting entry_id="EM1078" id="1">
<mmcif_em:details xsi:nil="true" />
<mmcif_em:method>AUTOMATIC</mmcif_em:method>
<mmcif_em:ref_protocol>RIGID BODY REFINEMENT</mmcif_em:ref_protocol>
<mmcif_em:ref_space>REAL</mmcif_em:ref_space>
<mmcif_em:target_criteria xsi:nil="true" />
</mmcif_em:em_3d_fitting>
<mmcif_em:em_3d_fitting entry_id="EM1078" id="2">
<mmcif_em:details xsi:nil="true" />
<mmcif_em:method>AUTOMATIC</mmcif_em:method>
<mmcif_em:ref_protocol>RIGID BODY REFINEMENT</mmcif_em:ref_protocol>
<mmcif_em:ref_space>REAL</mmcif_em:ref_space>
<mmcif_em:target_criteria xsi:nil="true" />
</mmcif_em:em_3d_fitting>
<mmcif_em:em_3d_fitting entry_id="EM1078" id="3">
<mmcif_em:details xsi:nil="true" />
<mmcif_em:method>AUTOMATIC</mmcif_em:method>
<mmcif_em:ref_protocol>RIGID BODY REFINEMENT</mmcif_em:ref_protocol>
<mmcif_em:ref_space>REAL</mmcif_em:ref_space>
<mmcif_em:target_criteria xsi:nil="true" />
</mmcif_em:em_3d_fitting>
</mmcif_em:em_3d_fittingCategory>
Example 2 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_3d_fittingCategory>
<mmcif_em:em_3d_fitting entry_id="1DYL" id="1">
<mmcif_em:details> THE CRYSTAL STRUCTURE OF THE CAPSID
PROTEIN FROM CHOI ET AL (1997) PROTEINS 3 27:345-359
(SUBUNIT A OF PDB FILE 1VCQ) WAS PLACED INTO THE CRYO-EM
DENSITY MAP. THE CAPSID PROTEIN WAS FIRST MANUALLY POSITIONED
INTO THE CRYO-EM DENSITY CORRESPONDING TO POSITIONS OF THE
FOUR INDEPENDENT MONOMER DENSITIES BETWEEN THE INNER LEAFLET
OF THE BILAYER AND THE RNA. THESE POSITIONS WERE THEN REFINED
BY RIGID BODY REFINEMENT IN REAL SPACE WITH THE PROGRAM EMFIT
(CHENG ET AL. 1995, CELL 80, 621-630). THE QUALITY OF THE FIT
CAN BE SEEN FROM THE MAP DENSITY WITHIN THE PROTEIN. ALL 4563
ATOMS ARE IN DENSITY OF AT LEAST 4 SIGMA (96.73) ABOVE THE
AVERAGE (512.04), 1167 ATOMS ARE IN DENSITY BETWEEN 4 AND 5
SIGMA, 3174 ATOMS ARE IN DENSITY BETWEEN 5 AND 6 SIGMA, AND 222
ATOMS ARE IN DENSTY OF 6 SIGMA OR ABOVE. THE VARIATION IN
DENSITY OVER THE FITTED PROTEIN CAN BE VISUALIZED WITH THE
PSEUDO TEMPERATURE FACTOR. THE DENSITY VALUE AT EACH ATOM IS
GIVEN IN THE 8TH COLUM (USUALLY THE OCCUPANCY) AS THE NUMBER
OF STANDARD DEVIATION ABOVE BACKGROUND. COLUMN NINE (USUALLY
THE TEMPERATURE FACTOR) CONTAINS THE VALUE OF THE RELATIVE
DENSITY WITHIN THE FITTED PROTEIN SCALED LINEARLY SO THAT THE
MINIMUM DENSITY IS 100.0 AND THE MAXIMUM DENSITY IS 1.0. THE
ATOMS THAT LIE IN THE LOWER DENSITY REGIONS WILL HAVE THE
HIGHEST PSEUDO TEMPERATURE FACTORS. </mmcif_em:details>
<mmcif_em:method>AUTOMATIC</mmcif_em:method>
<mmcif_em:ref_protocol>RIGID BODY REFINEMENT</mmcif_em:ref_protocol>
<mmcif_em:ref_space>REAL</mmcif_em:ref_space>
<mmcif_em:target_criteria>R-FACTOR</mmcif_em:target_criteria>
</mmcif_em:em_3d_fitting>
</mmcif_em:em_3d_fittingCategory>
Any additional details regarding fitting of atomic
coordinates into the 3d-em volume.
partial
Description of local variance of fit of the atomic coordinates into the
3dem volume map.
The method used to fit atomic coordinates
into the 3dem reconstructed map.
The overall B (temperature factor) value for the 3d-em volume.
Description of the quality of fit of the atomic coordinates into the
3dem volume map.
The type of protocol used in the refinement.
rigid body
A flag to indicate whether fitting was carried out in real
or reciprocal refinement space.
The quality of fit of the atomic coordinates into the
3dem volume map.
best visual fit using the program O
This data item is a pointer to _entry_id in
the ENTRY category.
The value of attribute id in category em_3d_fitting must uniquely identify
a fitting procedure of atomic coordinates
into 3dem reconstructed volume map.
Data items in the 3D_FITTING_LIST category
lists the methods of fitting atomic coordinates from a PDB file
into a 3d-em volume map file
Example 1 - based on EM entry 1078
<mmcif_em:em_3d_fitting_listCategory>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1" id="1">
<mmcif_em:end_seq>219</mmcif_em:end_seq>
<mmcif_em:entry_id>EM1078</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id>A</mmcif_em:fitted_pdb_chain_id>
<mmcif_em:fitted_pdb_entry_id>1PDF</mmcif_em:fitted_pdb_entry_id>
<mmcif_em:pdb_chain_id>A</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1EL6</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz>x, y, z</mmcif_em:start_pdb_symm_as_xyz>
<mmcif_em:start_seq>1</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31 xsi:nil="true" />
<mmcif_em:transform_matrix32 xsi:nil="true" />
<mmcif_em:transform_matrix33 xsi:nil="true" />
<mmcif_em:transform_matrix34 xsi:nil="true" />
<mmcif_em:transform_matrix41>2</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>EM1078</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1EL6</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1" id="B">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id>219</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id>B</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1PDF</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq>x, y, z</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31>3</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>1</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>EM1078</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1EL6</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>C</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>219</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1PDF</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="x, y, z" id="C">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id xsi:nil="true" />
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id xsi:nil="true" />
<mmcif_em:pdb_entry_id xsi:nil="true" />
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq xsi:nil="true" />
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21>4</mmcif_em:transform_matrix21>
<mmcif_em:transform_matrix22>1</mmcif_em:transform_matrix22>
<mmcif_em:transform_matrix23>EM1078</mmcif_em:transform_matrix23>
<mmcif_em:transform_matrix24>1EL6</mmcif_em:transform_matrix24>
<mmcif_em:transform_matrix31>A</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>1</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>219</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1PDF</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>D</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>x, y, z</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43 xsi:nil="true" />
<mmcif_em:transform_matrix44 xsi:nil="true" />
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1EL6" id="EM1078">
<mmcif_em:end_seq>H</mmcif_em:end_seq>
<mmcif_em:entry_id>B</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id>x, y, z</mmcif_em:fitted_pdb_entry_id>
<mmcif_em:pdb_chain_id>219</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq>1PDF</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31 xsi:nil="true" />
<mmcif_em:transform_matrix32 xsi:nil="true" />
<mmcif_em:transform_matrix33>9</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>EM1078</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1EL6</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>C</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1PDF" id="219">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id>I</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id xsi:nil="true" />
<mmcif_em:pdb_entry_id>x, y, z</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq xsi:nil="true" />
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23>10</mmcif_em:transform_matrix23>
<mmcif_em:transform_matrix24>1</mmcif_em:transform_matrix24>
<mmcif_em:transform_matrix31>EM1078</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>1EL6</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>A</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>219</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1PDF</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>J</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>x, y, z</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1" id="14">
<mmcif_em:end_seq>219</mmcif_em:end_seq>
<mmcif_em:entry_id>EM1078</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id>N</mmcif_em:fitted_pdb_chain_id>
<mmcif_em:fitted_pdb_entry_id>1PDF</mmcif_em:fitted_pdb_entry_id>
<mmcif_em:pdb_chain_id>B</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1EL6</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz>x, y, z</mmcif_em:start_pdb_symm_as_xyz>
<mmcif_em:start_seq>1</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31 xsi:nil="true" />
<mmcif_em:transform_matrix32 xsi:nil="true" />
<mmcif_em:transform_matrix33 xsi:nil="true" />
<mmcif_em:transform_matrix34 xsi:nil="true" />
<mmcif_em:transform_matrix41>15</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>EM1078</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1EL6</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1" id="C">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id>219</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id>O</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1PDF</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq>x, y, z</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31>16</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>1</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>EM1078</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1EL6</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>A</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>219</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1PDF</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="x, y, z" id="P">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id xsi:nil="true" />
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id xsi:nil="true" />
<mmcif_em:pdb_entry_id xsi:nil="true" />
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq xsi:nil="true" />
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21>17</mmcif_em:transform_matrix21>
<mmcif_em:transform_matrix22>1</mmcif_em:transform_matrix22>
<mmcif_em:transform_matrix23>EM1078</mmcif_em:transform_matrix23>
<mmcif_em:transform_matrix24>1EL6</mmcif_em:transform_matrix24>
<mmcif_em:transform_matrix31>B</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>1</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>219</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1PDF</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>Q</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>x, y, z</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43 xsi:nil="true" />
<mmcif_em:transform_matrix44 xsi:nil="true" />
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1H6W" id="EM1078">
<mmcif_em:end_seq>B</mmcif_em:end_seq>
<mmcif_em:entry_id>A</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id>1-y, 1+x-y, z</mmcif_em:fitted_pdb_entry_id>
<mmcif_em:pdb_chain_id>397</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>250</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq>1PDI</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31 xsi:nil="true" />
<mmcif_em:transform_matrix32 xsi:nil="true" />
<mmcif_em:transform_matrix33>22</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>2</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>EM1078</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1OCY</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>A</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>397</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1PDI" id="527">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id>B</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id xsi:nil="true" />
<mmcif_em:pdb_entry_id>1-y, 1+x-y, z</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq xsi:nil="true" />
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23>23</mmcif_em:transform_matrix23>
<mmcif_em:transform_matrix24>2</mmcif_em:transform_matrix24>
<mmcif_em:transform_matrix31>EM1078</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>1H6W</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>A</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>250</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>397</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1PDI</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>C</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>y-x, 1-x, z</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1OCY" id="EM1078">
<mmcif_em:end_seq>E</mmcif_em:end_seq>
<mmcif_em:entry_id>A</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id>1-y, 1+x-y, z</mmcif_em:fitted_pdb_entry_id>
<mmcif_em:pdb_chain_id>527</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>397</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq>1PDI</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31 xsi:nil="true" />
<mmcif_em:transform_matrix32 xsi:nil="true" />
<mmcif_em:transform_matrix33>29</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>2</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>EM1078</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1H6W</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>A</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>250</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1PDI" id="397">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id>F</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id xsi:nil="true" />
<mmcif_em:pdb_entry_id>y-x, 1-x, z</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq xsi:nil="true" />
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23>30</mmcif_em:transform_matrix23>
<mmcif_em:transform_matrix24>2</mmcif_em:transform_matrix24>
<mmcif_em:transform_matrix31>EM1078</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>1OCY</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>A</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>397</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>527</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1PDI</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>F</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>y-x, 1-x, z</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="2" id="34">
<mmcif_em:end_seq>527</mmcif_em:end_seq>
<mmcif_em:entry_id>EM1078</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id>H</mmcif_em:fitted_pdb_chain_id>
<mmcif_em:fitted_pdb_entry_id>1PDI</mmcif_em:fitted_pdb_entry_id>
<mmcif_em:pdb_chain_id>A</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1OCY</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz>1-y, 1+x-y, z</mmcif_em:start_pdb_symm_as_xyz>
<mmcif_em:start_seq>397</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31 xsi:nil="true" />
<mmcif_em:transform_matrix32 xsi:nil="true" />
<mmcif_em:transform_matrix33 xsi:nil="true" />
<mmcif_em:transform_matrix34 xsi:nil="true" />
<mmcif_em:transform_matrix41>35</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>2</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>EM1078</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1H6W</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="250" id="A">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id>397</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id>I</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1PDI</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq>y-x, 1-x, z</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31>36</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>2</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>EM1078</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1OCY</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>A</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>397</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>527</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1PDI</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="y-x, 1-x, z" id="I">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id xsi:nil="true" />
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id xsi:nil="true" />
<mmcif_em:pdb_entry_id xsi:nil="true" />
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq xsi:nil="true" />
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21>37</mmcif_em:transform_matrix21>
<mmcif_em:transform_matrix22>2</mmcif_em:transform_matrix22>
<mmcif_em:transform_matrix23>EM1078</mmcif_em:transform_matrix23>
<mmcif_em:transform_matrix24>1H6W</mmcif_em:transform_matrix24>
<mmcif_em:transform_matrix31>A</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>250</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>397</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1PDI</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>J</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>x, y, z</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43 xsi:nil="true" />
<mmcif_em:transform_matrix44 xsi:nil="true" />
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1H6W" id="EM1078">
<mmcif_em:end_seq>L</mmcif_em:end_seq>
<mmcif_em:entry_id>A</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id>y-x, 1-x, z</mmcif_em:fitted_pdb_entry_id>
<mmcif_em:pdb_chain_id>397</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>250</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq>1PDI</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31 xsi:nil="true" />
<mmcif_em:transform_matrix32 xsi:nil="true" />
<mmcif_em:transform_matrix33>42</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>2</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>EM1078</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1OCY</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>A</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>397</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1PDI" id="527">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id>L</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id xsi:nil="true" />
<mmcif_em:pdb_entry_id>y-x, 1-x, z</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq xsi:nil="true" />
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23>43</mmcif_em:transform_matrix23>
<mmcif_em:transform_matrix24>2</mmcif_em:transform_matrix24>
<mmcif_em:transform_matrix31>EM1078</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>1H6W</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>A</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>250</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>397</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1PDI</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>M</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>x, y, z</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="2" id="47">
<mmcif_em:end_seq>397</mmcif_em:end_seq>
<mmcif_em:entry_id>EM1078</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id>O</mmcif_em:fitted_pdb_chain_id>
<mmcif_em:fitted_pdb_entry_id>1PDI</mmcif_em:fitted_pdb_entry_id>
<mmcif_em:pdb_chain_id>A</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1H6W</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz>y-x, 1-x, z</mmcif_em:start_pdb_symm_as_xyz>
<mmcif_em:start_seq>250</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31 xsi:nil="true" />
<mmcif_em:transform_matrix32 xsi:nil="true" />
<mmcif_em:transform_matrix33 xsi:nil="true" />
<mmcif_em:transform_matrix34 xsi:nil="true" />
<mmcif_em:transform_matrix41>48</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>2</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>EM1078</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1OCY</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="397" id="A">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id>527</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id>O</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1PDI</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq>y-x, 1-x, z</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31>49</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>2</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>EM1078</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1H6W</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>A</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>250</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>397</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1PDI</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="x, y, z" id="P">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id xsi:nil="true" />
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id xsi:nil="true" />
<mmcif_em:pdb_entry_id xsi:nil="true" />
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq xsi:nil="true" />
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21>50</mmcif_em:transform_matrix21>
<mmcif_em:transform_matrix22>2</mmcif_em:transform_matrix22>
<mmcif_em:transform_matrix23>EM1078</mmcif_em:transform_matrix23>
<mmcif_em:transform_matrix24>1OCY</mmcif_em:transform_matrix24>
<mmcif_em:transform_matrix31>A</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>397</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>527</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1PDI</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>P</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>x, y, z</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43 xsi:nil="true" />
<mmcif_em:transform_matrix44 xsi:nil="true" />
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1OCY" id="EM1078">
<mmcif_em:end_seq>R</mmcif_em:end_seq>
<mmcif_em:entry_id>A</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id>y-x, 1-x, z</mmcif_em:fitted_pdb_entry_id>
<mmcif_em:pdb_chain_id>527</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>397</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq>1PDI</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31 xsi:nil="true" />
<mmcif_em:transform_matrix32 xsi:nil="true" />
<mmcif_em:transform_matrix33>55</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>3</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>EM1078</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1QEX</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>A</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1PDP" id="288">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id>A</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id xsi:nil="true" />
<mmcif_em:pdb_entry_id>x, y, z</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq xsi:nil="true" />
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23>56</mmcif_em:transform_matrix23>
<mmcif_em:transform_matrix24>3</mmcif_em:transform_matrix24>
<mmcif_em:transform_matrix31>EM1078</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>1QEX</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>B</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>288</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1PDP</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>B</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>x, y, z</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="3" id="60">
<mmcif_em:end_seq>288</mmcif_em:end_seq>
<mmcif_em:entry_id>EM1078</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id>F</mmcif_em:fitted_pdb_chain_id>
<mmcif_em:fitted_pdb_entry_id>1PDP</mmcif_em:fitted_pdb_entry_id>
<mmcif_em:pdb_chain_id>B</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1QEX</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz>y-x, -x, z</mmcif_em:start_pdb_symm_as_xyz>
<mmcif_em:start_seq>1</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31 xsi:nil="true" />
<mmcif_em:transform_matrix32 xsi:nil="true" />
<mmcif_em:transform_matrix33 xsi:nil="true" />
<mmcif_em:transform_matrix34 xsi:nil="true" />
<mmcif_em:transform_matrix41>61</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>3</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>EM1078</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1QEX</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1" id="A">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id>288</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id>G</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1PDP</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq>x, y, z</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31>62</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>3</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>EM1078</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1QEX</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>B</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>288</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1PDP</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="x, y, z" id="H">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id xsi:nil="true" />
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id xsi:nil="true" />
<mmcif_em:pdb_entry_id xsi:nil="true" />
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq xsi:nil="true" />
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21>63</mmcif_em:transform_matrix21>
<mmcif_em:transform_matrix22>3</mmcif_em:transform_matrix22>
<mmcif_em:transform_matrix23>EM1078</mmcif_em:transform_matrix23>
<mmcif_em:transform_matrix24>1QEX</mmcif_em:transform_matrix24>
<mmcif_em:transform_matrix31>A</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>1</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>288</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1PDP</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>I</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>-y, x-y, z</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43 xsi:nil="true" />
<mmcif_em:transform_matrix44 xsi:nil="true" />
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1QEX" id="EM1078">
<mmcif_em:end_seq>M</mmcif_em:end_seq>
<mmcif_em:entry_id>A</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id>x, y, z</mmcif_em:fitted_pdb_entry_id>
<mmcif_em:pdb_chain_id>288</mmcif_em:pdb_chain_id>
<mmcif_em:pdb_entry_id>1</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq>1PDP</mmcif_em:start_seq>
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23 xsi:nil="true" />
<mmcif_em:transform_matrix24 xsi:nil="true" />
<mmcif_em:transform_matrix31 xsi:nil="true" />
<mmcif_em:transform_matrix32 xsi:nil="true" />
<mmcif_em:transform_matrix33>68</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>3</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>EM1078</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1QEX</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>B</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>1</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
<mmcif_em:em_3d_fitting_list _3d_fitting_id="1PDP" id="288">
<mmcif_em:end_seq xsi:nil="true" />
<mmcif_em:entry_id>N</mmcif_em:entry_id>
<mmcif_em:fitted_pdb_chain_id xsi:nil="true" />
<mmcif_em:fitted_pdb_entry_id xsi:nil="true" />
<mmcif_em:pdb_chain_id xsi:nil="true" />
<mmcif_em:pdb_entry_id>x, y, z</mmcif_em:pdb_entry_id>
<mmcif_em:start_pdb_symm_as_xyz xsi:nil="true" />
<mmcif_em:start_seq xsi:nil="true" />
<mmcif_em:transform_matrix11 xsi:nil="true" />
<mmcif_em:transform_matrix12 xsi:nil="true" />
<mmcif_em:transform_matrix13 xsi:nil="true" />
<mmcif_em:transform_matrix14 xsi:nil="true" />
<mmcif_em:transform_matrix21 xsi:nil="true" />
<mmcif_em:transform_matrix22 xsi:nil="true" />
<mmcif_em:transform_matrix23>69</mmcif_em:transform_matrix23>
<mmcif_em:transform_matrix24>3</mmcif_em:transform_matrix24>
<mmcif_em:transform_matrix31>EM1078</mmcif_em:transform_matrix31>
<mmcif_em:transform_matrix32>1QEX</mmcif_em:transform_matrix32>
<mmcif_em:transform_matrix33>A</mmcif_em:transform_matrix33>
<mmcif_em:transform_matrix34>1</mmcif_em:transform_matrix34>
<mmcif_em:transform_matrix41>288</mmcif_em:transform_matrix41>
<mmcif_em:transform_matrix42>1PDP</mmcif_em:transform_matrix42>
<mmcif_em:transform_matrix43>O</mmcif_em:transform_matrix43>
<mmcif_em:transform_matrix44>-y, x-y, z</mmcif_em:transform_matrix44>
</mmcif_em:em_3d_fitting_list>
</mmcif_em:em_3d_fitting_listCategory>
The end sequence ID for the pdb entry chain
used in the fitting
The EM entry id pointer
The chain id for the resulting fitted coordinates
The PDB code for the entry produced by the fitting.
Description of a particular component pdb entry used in fitting.
The chain id for the entry used in fitting.
The PDB code for the entry used in fitting.
The symmetry required to be applied to the starting
PDB entry chain before starting the fitting procedure
The start sequence ID for the pdb entry chain
used in the fitting
The (1,1) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (1,2) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (1,3) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (1,4) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (2,1) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (2,2) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (2,3) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (2,4) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (3,1) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (3,2) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (3,3) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (3,4) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (4,1) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (4,2) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (4,3) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The (4,4) element of a 4,4 matrix relating
the starting PDB chain to the fitted coordinates
in the case of rigid body refinement
The value of attribute 3d_fitting_id in category em_3d_fitting_list is a pointer
to attribute id in category em_3d_fitting in the 3d_fitting category
This data item is a unique identifier.
Data items in the EM_3D_RECONSTRUCTION category
record details of the 3D reconstruction procedure from 2D projections.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_3d_reconstructionCategory>
<mmcif_em:em_3d_reconstruction entry_id="1DYL" id="1">
<mmcif_em:citation_id>1</mmcif_em:citation_id>
<mmcif_em:details xsi:nil="true" />
<mmcif_em:resolution>9</mmcif_em:resolution>
</mmcif_em:em_3d_reconstruction>
</mmcif_em:em_3d_reconstructionCategory>
The Amplitude correction method.
Frequency amplitude correction with X-ray scattering data enhances
the Fourier amplitudes of a reconstructed cryo-EM volume so they
more closely resemble those of experimental low-angle X-ray
scattering data. Normal amplitude correction (in which case the
SNR weighted averaging of particles will still occur properly) may
be applied or without it, in which case the (phase-flipped) data
is not corrected during averaging, then the final 3D model is 'fixed'.
Details of the B-factor correction method.
This data item is a pointer to attribute id in category citation in the
CITATION category.
The CTF-correction method.
The Contrast Transfer Function CTF compensation for low contrast
specimens (e.g. frozen-hydrated), for which phase contrast is the only
significant mechanism, then higher defocus levels must be used to
achieve any significant transfer, and several images at different
focus levels must be combined to complete the information lost from
the transfer gaps of any one image. The CTF correction can be applied
to each extracted particle separately or to the whole micrograph after
digitisation. The simplest level of compensation is to reverse phases
at the negative lobes of the CTF.
CTF correction of each particle
General details on the 3d recontruction
Orientation determination using the random-conical data
collection method. This method uses a defined geometry in
the data collection, and is able to find the handedness of
the structure unambiguously. Each specimen field is imaged
twice, once tilted, once untilted. Particles are selected
simultaneously from both untilted- and tilted-specimen fields,
using a special interactive particle-selection program that is
able to "predict" the location of a particle in the tilted-specimen
field when its counterpart has been selected in the untilted field.
From the untilted-specimen particle data set, all particles are
selected that exhibit the same view. This can be done by using
alignment followed by classification. The corresponding
tilted-specimen data subset can be used to compute a reconstruction:
the orientations of the tilted-particle projections lie on a cone
with fixed angle (the tilt angle) and random azimuths (the
in-plane angles found in the alignment of the untilted particle set).
1
Orientation determination using common lines (a.k.a.
"angular reconstitution"). This method is based on the fact that
in Fourier space any two projections intersect along a central line
("the common line"). Hence, in principle, the relative orientations
between three projections can be determined - except that the
handedness of the constellation is ambiguous. Because of the low
signal-to-noise ratio of raw particle images, averages of projections
falling into roughly the same orientation must be used. Since the
procedure leads to solutions presenting local minima, it must be
repeated several times to find solutions that form a cluster,
presumably around the global minimum. Such clustering of solutions
can be detected by multivariate statistical analysis of the resulting
3D maps. Two clusters are expected, one for each enantiomorph.
After initial structure is obtained, it should be further refined
using 3D projection matching strategy described next.
2
Orientation determination by 3D projection matching. Here the
existing 3D map is projected in many orientations on a regular
angular grid, and the resulting projections that are compared,
one by one, with each of the experimental projections. This comparison
(by cross-correlation ) yields a refined set of Eulerian angles ,
with which a refined reconstruction can be computed using one
of the possible reconstruction techniques. This procedure requires
iteration until the angles for each projection stabilize.
3
Details of the envelope function correction method.
The average phase residual for the helical assembly.
The layer-line resolution. Layer-lines fade out and are only visible
to a certain resolution.
The number of datasets used in the 3d reconstruction for the helical assembly.
Details on how located layer lines are used to choose a selection rule
which best fits the data. Based on this selection rule the filament is
then reboxed and restraightened using the original digitized image so
that the final image contains an integral number of helical repeats.
The selection rule define helical lattices which relate the layer-
line number l to the order of the Bessel function, n, contributing
to the layer-line. (n is the start number, ie number around the
circumference, of the contributing helix).
The diffraction pattern from a helix consists not of discrete spots
but of difraction spots which have been broadened into layer-lines.
The order of the Bessel functions allowed to contribute to the
diffraction pattern of a helix on a given layer line versus the
layer line along the ordinate gives a function which is described
by a lattice. Such a plot is analogous to the diffraction pattern
from a planar array corresponding to a flattened helix and is called
an (n,l) plot.
e.g. the n,l plot corresponding to the selection rule l = 5n + 12m
where m is an integer and indicates e.g. 12 (ribosomes) per repeat
five turns long, whilst the n,l plot corresponding to the selection
rule l = 5n + 17m indicates 17(ribosomes) per repeat five turns along.
General details describing any local or approximate symmetry used in
the single particle reconstruction
The algorithm method used for the 3d-reconstruction.
e.g.
Random-conical reconstruction:
a method of data collection and reconstruction used for single particles,
typically used initially in a project, to obtain a first low-resolution
reconstruction of the macromolecule [Radermacher et al., 1987]. Two images
of the same specimen field are collected, one with untilted grid, the
other with the grid tilted by 50 to 60 degrees. Any set of particles
presenting the same view in the untilted-specimen image form a
random-conical projection set in the associated tilted-specimen image.
Helical reconstruction
Helical reconstruction is used when the protein of interest forms a
natural helix. Since the helix is a recurring structure with a very
well defined pattern, the repeating pattern of the helix can be
exploited to solve the structure. In this case, no alignment of the
particles is needed, since the individual positions of subunits within
the helix are clearly defined by the shape of the helix. Two common
examples of structures solved by helical reconstruction are TMV and
microtubules.
Icosahedral reconstruction
Icosahedral reconstructions also take advantage of internal symmetry
and repetition to generate a detailed three-dimensional structure from
the data set. In this case, the symmetry is icosahedral (twenty-one sided).
Many viruses exhibit icosahedral symmetry in their capsid proteins,
and this method has been used to solve their structures.
Electron crystallography
Electron crystallography is similar to x-ray crystallography in that it
exploits the repeating pattern found within a crystal to generate a
structure. Just as with x-ray crystallography, difraction patterns are
generated and are used to define an electron density map. However, it
differs in that the crystal used is a two-dimensional sheet as opposed
to three three-dimensional crystals of x-ray crystallography.
Common Lines
Another reconstruction method searches for the intersection of any two
projections in Fourier space. The Fourier transform of the experimental
projections all form slices around a common core in Fourier space.
Therefore, the intersection of these projections are unique (unless the
projections perfectly overlap), and their relative orientation can be
found when three or more projections are used. A principal problem with
this method is that the handedness of the image is lost. This, however,
can later be corrected by visual examination of the model with other
known structural information.
Back Projection
As its name implies, back projection is the inverse function of projection.
When an n-dimensional object is projected, each projection is an n-1
dimensional sum of its density along the projection axis. Therefore, a
sphere would have circles as its projections. A cube, on the other hand,
would produce either squares, diamonds, or other intermediate parallelograms
depending on the direction of projection. The actual shape, of course,
depends on the orientation from which the projection was made. The reverse
function is called back projection and regenerates the original object.
cross-common lines
The number of asymmetric units used in
the single particle reconstruction
The number of particles used in the 3d reconstruction
The final resolution (in angstroms)of the 3d reconstruction.
The method used to determine the final resolution
of the 3d reconstruction.
The Fourier Shell Correlation criterion as a measure of
resolution is based on the concept of splitting the (2D)
data set into two halves; averaging each and comparing them
using the Fourier Ring Correlation (FRC) technique.
FSC at 0.5 cut-off
The actual pixel size of projection set of images in x
IF only attribute voxel_size_x in category em_3d_reconstruction is given
then a cube is assumed.
The actual pixel size of projection set of images in y
IF only attribute voxel_size_x in category em_3d_reconstruction is given
then a cube is assumed.
The actual pixel size of projection set of images in z
IF only attribute voxel_size_x in category em_3d_reconstruction is given
then a cube is assumed.
This data item is a pointer to attribute id in category entry in the ENTRY category.
The value of attribute id in category em_3d_reconstruction must
uniquely identify the 3d reconstruction.
Data items in the EM_3D_REFINEMENT category record details
about the class/particle refinement.
In random conical tilt, images were assigned angular positions through
rotational alignment and tilt-angles. From each different class, a
three-dimensional preliminary model is constructed. To improve the output,
those preliminary models from each class that have a high degree of
similarity are merged. In theory, these models corresponded to groups
of the same molecule just viewed from different orientations. Once all
the good random conical tilt models (and their corresponding particle
data sets) have been merged, iterative angular refinement is used to
improve the model's resolution. Equidistant projections are first
generated from the merged model. The entire particle data set (whether
the old random conical tilt experimental particles, or new untilted
experimental particles, or both) is then cross correlated to each
reference projection. A correlation coefficient is generated between
each experimental particle and reference projection. For each individual
experimental particle, it is matched to the reference projection that
gave the highest correlation coefficient. Therefore, it is assumed that
this particle matches the Euler angles of the reference projection.
Alignment radius (pixels) used in alignment search
the angular_search_step_size used in refinement
Convergence criterion fraction
e.g. Converges when x16 % of all images move < 1.5 * stepsize
This data item is a pointer to attribute id in category entry in the ENTRY category.
the max_spatial_frequency used in refinement (1/A)
The criterion used to determine the maximum spatial frequency.
Description of the 3d refinement method
the number of iterations used in refinement
The number of particles used in refinement.
the Projection radius in pixels
the structure_radius in pixels
The value of attribute id in category em_3d_refinement must uniquely identify
the refinement used in the em experiments.
Data items in the EM_ARRAY_FORMATION category
record details of growth conditions for the array
samples.
Example 1 - based on PDB entry 1AT9 and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_array_formationCategory>
<mmcif_em:em_array_formation id="1" type="2D-CRYSTAL">
<mmcif_em:apparatus xsi:nil="true" />
<mmcif_em:atmosphere>room air</mmcif_em:atmosphere>
<mmcif_em:buffer_id>2</mmcif_em:buffer_id>
<mmcif_em:citation_id>2</mmcif_em:citation_id>
<mmcif_em:details>on grid</mmcif_em:details>
<mmcif_em:method xsi:nil="true" />
<mmcif_em:pH>5.2</mmcif_em:pH>
<mmcif_em:temp>18</mmcif_em:temp>
<mmcif_em:time xsi:nil="true" />
</mmcif_em:em_array_formation>
</mmcif_em:em_array_formationCategory>
The type of the apparatus used for growing the array.
Langmuir trough
The type of atmosphere in which arrays were grown.
room air
This data item is a pointer to attribute id in category em_solution_composition.
This data item is a pointer to attribute id
in category citation in the CITATION category.
Any additional items concerning array growth.
Two-dimensional Crystallization-- Purified protein (2 mg/ml) was mixed
with E. coli lipids solubilized in OTG (mixed micelles stock solution,
4 mg/ml E. coli lipids in 20 mM Mes-NaOH (pH 6), 5% OTG, 0.01% NaN3)
to achieve a lipid to protein ratio of 1 (w/w). The final protein
concentration was adjusted to 1.33 mg/ml, and the final OTG content
was adjusted to 1.93%. The reconstitution mixture (60 microliters)
was preincubated at room temperature for 30 min and dialyzed against
1.5 liters of 10 mM Mes-NaOH (pH 6), 100 mM NaCl, 100 mM MgCl2,
2 mM dithiothreitol, 0.01% NaN3 for 24 h at room temperature,
24 h at 37 C, and another 24 h at room temperature.
The method used for growing the array.
lipid monolayer
the pH value used for growing the array.
4.7
This data item is a pointer to attribute id in category em_solution_composition in the
EM_SOLUTION_COMPOSITION category.
The value of the temperature in degrees Kelvin used for
growing the arrays.
293
The length of time required to grow the array.
approximately 2 days
The value of attribute id
in category em_array_formation must uniquely identify the sample.
The value of attribute type
in category em_array_formation must identifies the type of array studied.
Data items in the em_assembly category record basic information
about the assembly represented by the EM map.
based on PDB entry 1DGI
<mmcif_em:em_assemblyCategory>
<mmcif_em:em_assembly entry_id="1DGI" id="1">
<mmcif_em:array>NO</mmcif_em:array>
<mmcif_em:composition>virus-receptor complex</mmcif_em:composition>
<mmcif_em:name>Poliovirus-CD155</mmcif_em:name>
<mmcif_em:num_components>2</mmcif_em:num_components>
<mmcif_em:superstructure>NO</mmcif_em:superstructure>
</mmcif_em:em_assembly>
</mmcif_em:em_assemblyCategory>
based on PDB entry 2BG9
<mmcif_em:em_assemblyCategory>
<mmcif_em:em_assembly entry_id="2BG9" id="1">
<mmcif_em:array>YES</mmcif_em:array>
<mmcif_em:composition>integral membrane receptor</mmcif_em:composition>
<mmcif_em:name>Acetylcholine receptor, Torpedo postsynaptic membrane</mmcif_em:name>
<mmcif_em:num_components>1</mmcif_em:num_components>
<mmcif_em:superstructure>YES</mmcif_em:superstructure>
</mmcif_em:em_assembly>
</mmcif_em:em_assemblyCategory>
A flag to indicate whether the imaged assembly
is part of a regular array, e.g, a 2D or helical crystal.
The known composition of the sample.
Any additional details about the assembly.
The name of the biological assembly
helical crystals of acetylcholine receptor
poliovirus - CD155 receptor complex
The number of components of the biological assembly.
A flag to indicate whether the imaged assembly
is part of a larger structure, e.g., a membrane, virus, or cell.
This data item is a pointer to attribute id in category entry in the ENTRY category.
The value of attribute id in category em_assembly must uniquely identify
the EM experiment.
Data items in the EM_CLASSES category record details
about the particle classification.
Particle classification involves grouping images that are similar,
and separating images that are distinct. In practical use, this means
that experimental projections that have the same orientation (shape)
are placed within the same category for later averaging. In this case,
orientation means that the particles are showing the same face to the
viewer and the only difference between them is that they can be rotated
by some angle in the plane of the image. The experimental projections
might also be shifted relative to each other, but the centering of
the experimental projections is often done before classification.
is this required?
E(e1,e2,e3) = E(w,h,i)
cos(i)cos(h)cos(w)-sin(i)sin(h) cos(i)cos(h)sin(w)+sin(i)sin(h) -cos(i)sin(h)
-sin(i)cos(h)cos(w)-cos(i)sin(h) sin(i)cos(h)sin(w)+cos(i)sin(h) sin(i)sin(h)
sin(h)cos(w) sin(h)sin(w) cos(h)
The alignment_method used
The percentage angular error threshold
The average_angular_error in degrees
The average_translational_pixel_shift_error
The clustering_method used
Description of the classes derived in the em experiments.
We have used size variation analyses to classify images recorded
from preparations of the WT S. cerevisiae PDC to which sufficient
E1 was added to occupy its 60 binding sites and the same preparation
with about one-third of the E1 binding sites occupied. Two 3D
reconstructions representative of images that vary in size by 10-12%
(~50 Angstroms in diameter) from these preparations were computed to
document the E1 organization about the core and the length of its
inner linkers.
In this regard, our previous structure of the WT bovine kidney PDC in
which ~22 E1s were bound indicated that the outer shell could readily
accommodate 60 molecules of E1 without significant crowding. Surprisingly,
this study shows that extensive E1 binding favors a more extended inner
linker and an altered arrangement of E1 about the core.
1
The focal pair method of orientation determination, refinement, and
3D reconstruction as implemented in the IMIRS software package was
used except that an additional step of particle-size evaluation was
performed in the current reconstruction. Data sets consisting of
1,500 and 690 particle images of PDC with a molar ratio of 60 E1/E2
core and ~24 E1/E2 core, respectively, were processed. For both data
sets, an iterative procedure was implemented to classify the particles
according to their sizes by using the SIZEDIFF program with contrast
transfer function correction incorporated. A preliminary 3D reconstruction
was calculated by combining all of the particles, and this "average"
reconstruction was used to classify the images into a 1.0 size group
comprising a 3% size variation of the images. For the PDC with ~60
E1/E2 core, the converged structure from 128 images in the 1.0 size
group, was then used as a model to classify 45 and 80 images in the
0.95 and 1.05 size groups, respectively. For the WT PDC preparation
(24 E1/E2 core) the converged structure from 80 images in the 1.0
size group was used as model to classify 46 and 53 images in the
0.95 and 1.05 size groups, respectively. The image size distribution
appears bell-shaped and is consistent with a more extensive data set
of the human PDC (Y.G., Z.H.Z., Y. Hiromasa, H. Bao, X. Yan,
T. E. Roche, and J.K.S., unpublished results). The finding that 1.0
size groups consist of the larger and smaller reconstructions in the
PDC preparations according to their greater or lesser degree of
E1 occupancy, respectively, indicates that the extent of E1 binding
is related to the variable size of the molecules.
2
A classification was performed using the self-organizing map (SOM)
algorithms of the XMIPP package. The entire set was first low
pass-filtered to 3.2 nm, and a reference-free alignment was performed
using the Spider software package. Transformations in x, y, and
in-plane angle were imposed, and the data set was fed to the kernel
density SOM procedure using a 10 x 10 grid. The procedure generates
a grid of code vectors that represent the assigned images. It was
verified that clean looking code vectors represented classes of clean
particles, while particles assigned to defect-ridden code vectors were
themselves of poor quality. The procedure was repeated several times
with different parameters, and in each case a set of roughly 3000 good
particles was obtained. Further processing was conducted on a set
containing 2943 particles.
3
The picked particles were submitted to a multivariate statistical
analysis without alignment and were classified into clusters of
particles with similar features. To this end, a program package
kindly provided by J. P. Bretaudiere was used. The various cluster
averages revealed square and round shaped particles at different
angular orientations. These averages were taken as references for
subsequent angular and translational alignment of the extracted 4096
particles. Aligned particles were classified again, and cluster
averages were calculated.
4
This data item is a pointer to attribute id in category entry in the ENTRY category.
The euler angle about z-axis
The euler angle about y-axis
The second euler angle about z-axis
The fractional_minimum_amplitude
The global_correlation_coefficient
The global_real-space_correlation_coefficient
flag for method used for internal resolution
The number of particles used in the class average
The class origin in X
The class origin in Y
The value of attribute id in category em_classes must uniquely identify
the classes used in the em experiments.
Data items in the EM_CRYO_STAIN category record details
about the staining techniques used.
Text describing a reference citation
on the staining techniques used
If the details given are for a cryogen staining
method the name of the cryogen used
General details on the staining techniques used
The humidity at which the staining technique was used
Details on the instrument used in the staining technique
used
Text describing the protocol for the staining techniques used
A pointer to attribute id in category em_sample_preparation in the
EM_SAMPLE_PREPARATION category
The staining technique temperature used
Text giving details on the time factors
involved in the staining techniques used
The general class or type of the staining technique
used
This data item is a pointer to attribute id
in category entry in the ENTRY category.
The value of attribute id in category em_cryo_stain must uniquely identify
set of stain parameters
Data items in the EM_DETECTOR category record details
of the image detector type.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_detectorCategory>
<mmcif_em:em_detector entry_id="1DYL" id="1">
<mmcif_em:type>FILM</mmcif_em:type>
</mmcif_em:em_detector>
</mmcif_em:em_detectorCategory>
The detector type used for recording images.
Usually film or CCD camera.
This data item is a pointer to attribute id in category entry in the ENTRY category.
The value of attribute id in category em_detector must uniquely identify
the detector used for imaging.
Data items in the EM_DETECTOR_CCD category record details
of the CCD detector type.
Example 1 -
<mmcif_em:em_detector_CCDCategory>
<mmcif_em:em_detector_CCD detector_id="1">
<mmcif_em:details xsi:nil="true" />
</mmcif_em:em_detector_CCD>
</mmcif_em:em_detector_CCDCategory>
Any additional information about the detection system.
The detector dimension in x
The detector dimension in y
The CCD detector model used for recording images.
The detector pixel size
The value of attribute detector_id in category em_detector_CCD must uniquely identify
the description of the CCD detector.
The value of attribute detector_id in category em_detector_CCD is a pointer to
attribute id in category em_detector in category EM_DETECTOR.
Data items in the EM_DETECTOR_FILM category record details
of the image detector type.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
Any additional information about the detection system.
The detector dimension in x
The detector dimension in y
Description of film_processing_conditions
The film type used for recording images.
The value of attribute detector_id in category em_detector_film must uniquely identify
the characteristics of the film detector.
The value of attribute detector_id in category em_detector_film is a pointer to
attribute id in category em_detector in category EM_DETECTOR.
The EM_ELECTRON_DIFFRACTION category records basic
information about electron diffraction experiment.
Example 1 - based on PDB entry 1TUB and laboratory records for the
structure corresponding to PDB entry 1TUB
<mmcif_em:em_electron_diffractionCategory>
<mmcif_em:em_electron_diffraction entry_id="1TUB" id="1">
<mmcif_em:d_res_high>3.7</mmcif_em:d_res_high>
<mmcif_em:details xsi:nil="true" />
<mmcif_em:num_diff_patterns>94</mmcif_em:num_diff_patterns>
<mmcif_em:num_images>149</mmcif_em:num_images>
<mmcif_em:num_unique_reflections>12000</mmcif_em:num_unique_reflections>
<mmcif_em:tilt_range_max>55</mmcif_em:tilt_range_max>
<mmcif_em:tilt_range_min>0</mmcif_em:tilt_range_min>
</mmcif_em:em_electron_diffraction>
</mmcif_em:em_electron_diffractionCategory>
the highest resolution d-value for the electron diffraction experiment.
5.0
Details of the electron diffraction experiment
THE MODEL WAS DERIVED USING ELECTRON DIFFRACTION
AND IMAGE DATA FROM TWO DIMENSIONAL CRYSTALS OF TUBULIN
INDUCED BY THE PRESENCE OF ZN++ IONS.
WHAT FOLLOWS ARE THE COORDINATES FOR THE AB-TUBULIN DIMER
BOUND TO TAXOL AS OBTAINED BY ELECTRON CRYSTALLOGRAPHY OF
ZINC-INDUCED SHEETS. THIS IS THE UNREFINED MODEL, BUILT
INTO A RAW DENSITY MAP WHERE THE RESOLUTION IN THE PLANE
OF THE SHEET WAS 3.7 ANGSTROMS AND THAT PERPENDICULAR TO
THE SHEET ABOUT 4.8 ANGSTROMS. THE MODEL DOES NOT CONTAIN
MOST OF THE C-TERMINAL RESIDUES OF EITHER MONOMER WHICH
WERE DISORDERED IN THE MAP. THE LOOP BETWEEN HELIX H1 AND
STRAND S2, AND THAT BETWEEN H2 AND S3 ARE PRESENT FOR
COMPLETENESS BUT WERE BUILT INTO VERY WEAK DENSITY.
GIVEN THE LIMITED RESOLUTION OF THE MAP, THE CONFORMATION
OF THE SIDE CHAINS, ESPECIALLY THOSE CORRESPONDING TO
RESIDUES ON THE SURFACE OF THE DIMER, MUST BE TAKEN
CAUTIOUSLY. IN ADDITION, BECAUSE THIS IS AN UNREFINED
MODEL, CERTAIN GEOMETRY ERRORS MAY STILL BE PRESENT IN THE
STRUCTURE. PLEASE TAKE THIS INTO ACCOUNT WHEN
INTERPRETING YOUR OWN DATA BASED ON THE PRESENT TUBULIN
STRUCTURE. ALTHOUGH THE POSITION OF RESIDUES (WITH THE
EXCEPTION OF THOSE IN THE LOOPS MENTIONED ABOVE) SHOULD
NOT CHANGE SIGNIFICANTLY UPON REFINEMENT, DRAWING
INFORMATION AT THE LEVEL OF SIDE CHAIN CONFORMATION IS
CLEARLY NOT ADVISED. FINALLY, PLEASE NOTICE THAT THE
TAXOID IN THE MODEL IS THE TAXOL DERIVATIVE TAXOTERE.
1
The number of diffraction patterns collected in the electron
diffraction experiment.
The number of 2D crystal images collected in the electron
diffraction experiment.
The total number of structure factors measured
in the electron diffraction experiment, before merging to a unique set.
25743
The number of unique structure factors from the electron diffraction experiment.
12000
the overall phase error in degrees.
the rejection criteria (phase error) in degrees.
The maximum tilt angle used in the electron diffraction experiment.
The minimum tilt angle used in the electron diffraction experiment.
This data item is a pointer to attribute id in category entry in the ENTRY category.
The value of attribute id in category electron_diffraction must
uniquely identify the electron diffraction experiment.
data items in the em_electron_diffraction_shell category
record details about the quality of the phase information
within a specified resolution range.
based on pdb entry 1TUB
<mmcif_em:em_electron_diffraction_shellCategory>
<mmcif_em:em_electron_diffraction_shell electron_diffraction_id="1" id="1">
<mmcif_em:d_res_high>4.0</mmcif_em:d_res_high>
<mmcif_em:d_res_low>5.0</mmcif_em:d_res_low>
<mmcif_em:residual>36</mmcif_em:residual>
</mmcif_em:em_electron_diffraction_shell>
<mmcif_em:em_electron_diffraction_shell electron_diffraction_id="1" id="2">
<mmcif_em:d_res_high>3.7</mmcif_em:d_res_high>
<mmcif_em:d_res_low>4.0</mmcif_em:d_res_low>
<mmcif_em:residual>46</mmcif_em:residual>
</mmcif_em:em_electron_diffraction_shell>
</mmcif_em:em_electron_diffraction_shellCategory>
the highest resolution d-value for the resolution range.
5.0
the lowest resolution d-value for the resolution range.
4.0
the phase residual value for the electron diffraction experiment.
this data item is a pointer to attribute id in category em_electron_diffraction
in the em_electron_diffraction category.
the value of attribute id in category electron_diffraction_shell must
uniquely identify a resolution range of the electron diffraction data.
data items in the em_electron_diffraction_tilt_angle category
record details about data collected at a specific tilt angle.
based on pdb entry 1TUB
<mmcif_em:em_electron_diffraction_tilt_angleCategory>
<mmcif_em:em_electron_diffraction_tilt_angle electron_diffraction_id="1" id="1">
<mmcif_em:num_images>12</mmcif_em:num_images>
<mmcif_em:num_patterns>18</mmcif_em:num_patterns>
<mmcif_em:tilt_angle>0</mmcif_em:tilt_angle>
</mmcif_em:em_electron_diffraction_tilt_angle>
<mmcif_em:em_electron_diffraction_tilt_angle electron_diffraction_id="1" id="2">
<mmcif_em:num_images>51</mmcif_em:num_images>
<mmcif_em:num_patterns>57</mmcif_em:num_patterns>
<mmcif_em:tilt_angle>45</mmcif_em:tilt_angle>
</mmcif_em:em_electron_diffraction_tilt_angle>
<mmcif_em:em_electron_diffraction_tilt_angle electron_diffraction_id="1" id="3">
<mmcif_em:num_images>86</mmcif_em:num_images>
<mmcif_em:num_patterns>19</mmcif_em:num_patterns>
<mmcif_em:tilt_angle>55</mmcif_em:tilt_angle>
</mmcif_em:em_electron_diffraction_tilt_angle>
</mmcif_em:em_electron_diffraction_tilt_angleCategory>
the number of images measured at the specified tilt angle.
51
the number of diffraction patterns measured at the specified tilt angle.
57
the tilt angle at which diffraction data and/or images were obtained.
45.0
this data item is a pointer to attribute id in category em_electron_diffraction
in the EM_ELECTRON_DIFFRACTION category.
the value of attribute id in category electron_diffraction_tilt_angle must
uniquely identify the tilt angle.
Data items in the EM_EMBEDDING_AGENT category record details
about the type of reagents into which the sample was embedded
Details on a reference citation on the embedding agent used
General details on the embedding agent used
The temperature the embedding agent was used at
Details about the effect of time resolution for
the embedding agent used
The type of embedding agent used
This data item is a pointer to attribute id
in category entry in the ENTRY category.
The value of attribute id in category em_embedding_agent must uniquely identify
set of the embedding agent parameters
The EM_ENTITY_ASSEMBLY category defines a hierarchy-independent
list of assemblies relevant to the EM experiment.
The recommended convention is that the imaged assembly, defined
in the category EM_ASSEMBLY, is listed first.
Components, arrays and superstructures of the assembly
are also described.
The hierarchy independence enables descriptions of
symmetry, sample preparation, particle selection, and map masks
at multiple levels.
based on PDB entry 1DGI
<mmcif_em:em_entity_assemblyCategory>
<mmcif_em:em_entity_assembly id="1">
<mmcif_em:assembly_id>1</mmcif_em:assembly_id>
<mmcif_em:name>poliovirus-CD155 complex</mmcif_em:name>
<mmcif_em:symmetry_type>point symmetry</mmcif_em:symmetry_type>
<mmcif_em:type>COMPLEX ASSEMBLY</mmcif_em:type>
</mmcif_em:em_entity_assembly>
<mmcif_em:em_entity_assembly id="2">
<mmcif_em:assembly_id>1</mmcif_em:assembly_id>
<mmcif_em:name>poliovirus</mmcif_em:name>
<mmcif_em:symmetry_type>point symmetry</mmcif_em:symmetry_type>
<mmcif_em:type>VIRUS</mmcif_em:type>
</mmcif_em:em_entity_assembly>
<mmcif_em:em_entity_assembly id="3">
<mmcif_em:assembly_id>1</mmcif_em:assembly_id>
<mmcif_em:name>CD155 receptor</mmcif_em:name>
<mmcif_em:symmetry_type>asymmetric</mmcif_em:symmetry_type>
<mmcif_em:type>PROTEIN</mmcif_em:type>
</mmcif_em:em_entity_assembly>
</mmcif_em:em_entity_assemblyCategory>
based on PDB entry 2BG9
<mmcif_em:em_entity_assemblyCategory>
<mmcif_em:em_entity_assembly id="1">
<mmcif_em:assembly_id>1</mmcif_em:assembly_id>
<mmcif_em:name>acetylcholine receptor</mmcif_em:name>
<mmcif_em:symmetry_type>asymmetric</mmcif_em:symmetry_type>
<mmcif_em:type>PROTEIN</mmcif_em:type>
</mmcif_em:em_entity_assembly>
<mmcif_em:em_entity_assembly id="2">
<mmcif_em:assembly_id>1</mmcif_em:assembly_id>
<mmcif_em:name>torpedo post-synaptic membrane</mmcif_em:name>
<mmcif_em:symmetry_type xsi:nil="true" />
<mmcif_em:type>MEMBRANE</mmcif_em:type>
</mmcif_em:em_entity_assembly>
<mmcif_em:em_entity_assembly id="3">
<mmcif_em:assembly_id>1</mmcif_em:assembly_id>
<mmcif_em:name>helical crystal</mmcif_em:name>
<mmcif_em:symmetry_type>helical</mmcif_em:symmetry_type>
<mmcif_em:type>ARRAY</mmcif_em:type>
</mmcif_em:em_entity_assembly>
</mmcif_em:em_entity_assemblyCategory>
This data item is a pointer to attribute id in category em_assembly in the
em_assembly category.
Additional details about the component.
The Gene Ontology (GO) identifier for the component.
The GO id is the appropriate identifier used by the Gene Ontology
Consortium. Reference: Nature Genetics vol 25:25-29 (2000).
GO:0005876
GO:0015630
The InterPro (IPR) identifier for the component.
The IPR id is the appropriate identifier used by the Interpro Resource.
Reference: Nucleic Acid Research vol 29(1):37-40(2001).
001304
002353
The name of the component of the observed assembly.
The cell from which the component was
obtained.
CHO
HELA
3T3
The cellular location of the component.
cytoplasm
endoplasmic reticulum
plasma membrane
A flag to indicate whether the component is engineered.
The expression system used to produce the component.
eschericia coli
saccharomyces cerevisiae
The plasmid used in the expression system used to produce the component.
pBR322
pMB9
The organelle from which the component was
obtained.
golgi
mitochondrion
cytoskeleton
The common name of the species of the natural organism from which
the component was obtained.
The species of the natural organism from which the component
was obtained.
The strain of the natural organism from which the component was
obtained, if relevant.
DH5a
BMH 71-18
The tissue of the natural organism from which the component was
obtained.
heart
liver
eye lens
The type of symmetry of the assembly, component or superstructure.
Alternative name of the component.
FADV-1
A description of the biological structure type of
the assembly, component, or superstructure.
For assemblies containing multiple components,
use 'COMPLEX ASSEMBLY'.
The value of attribute id in category em_entity_assembly must uniquely identify
the assembly, component, or superstructure.
; attribute name in category item '_em_entity_assembly.id
Data items in the EM_ENTITY_ASSEMBLY_LIST category record details
of the molecular entities within the assembly.
based on PDB entry 1DGI
<mmcif_em:em_entity_assembly_listCategory>
<mmcif_em:em_entity_assembly_list assembly_id="1" entity_id="1" id="VP1">
<mmcif_em:number_of_copies>60</mmcif_em:number_of_copies>
</mmcif_em:em_entity_assembly_list>
<mmcif_em:em_entity_assembly_list assembly_id="1" entity_id="2" id="VP2">
<mmcif_em:number_of_copies>60</mmcif_em:number_of_copies>
</mmcif_em:em_entity_assembly_list>
<mmcif_em:em_entity_assembly_list assembly_id="1" entity_id="3" id="VP3">
<mmcif_em:number_of_copies>60</mmcif_em:number_of_copies>
</mmcif_em:em_entity_assembly_list>
<mmcif_em:em_entity_assembly_list assembly_id="1" entity_id="4" id="VP4">
<mmcif_em:number_of_copies>60</mmcif_em:number_of_copies>
</mmcif_em:em_entity_assembly_list>
<mmcif_em:em_entity_assembly_list assembly_id="1" entity_id="5" id="CD155frag">
<mmcif_em:number_of_copies>60</mmcif_em:number_of_copies>
</mmcif_em:em_entity_assembly_list>
</mmcif_em:em_entity_assembly_listCategory>
based on PDB entry 2BG9
<mmcif_em:em_entity_assembly_listCategory>
<mmcif_em:em_entity_assembly_list assembly_id="1" entity_id="1" id="alpha">
<mmcif_em:number_of_copies>2</mmcif_em:number_of_copies>
</mmcif_em:em_entity_assembly_list>
<mmcif_em:em_entity_assembly_list assembly_id="1" entity_id="2" id="beta">
<mmcif_em:number_of_copies>1</mmcif_em:number_of_copies>
</mmcif_em:em_entity_assembly_list>
<mmcif_em:em_entity_assembly_list assembly_id="1" entity_id="3" id="gamma">
<mmcif_em:number_of_copies>1</mmcif_em:number_of_copies>
</mmcif_em:em_entity_assembly_list>
<mmcif_em:em_entity_assembly_list assembly_id="1" entity_id="4" id="delta">
<mmcif_em:number_of_copies>1</mmcif_em:number_of_copies>
</mmcif_em:em_entity_assembly_list>
</mmcif_em:em_entity_assembly_listCategory>
The oligomeric state of the entity.
The value (in daltons) of the molecular weight of each component
of the assembly determined by attribute mol_wt_method in category em_entity_assembly_list.
The method used in determining
the molecular weight.
The number of copies of the entity within the assembly.
This data item is a pointer to attribute id in category em_assembly in
the EM_ASSEMBLY category.
A pointer to entity id.
The value of attribute id in category em_entity_assembly_list must uniquely identify
the component.
Data items in the EM_ENTITY_ASSEMBLY_MOL_WT category record details
of the molecular weight of structural elements in each component.
Example 1 - microtubule
<mmcif_em:em_entity_assembly_mol_wtCategory>
<mmcif_em:em_entity_assembly_mol_wt entity_assembly_id="1" id="1">
<mmcif_em:details>predicted from gene sequence</mmcif_em:details>
<mmcif_em:mol_wt>12000</mmcif_em:mol_wt>
<mmcif_em:mol_wt_method>calculated</mmcif_em:mol_wt_method>
</mmcif_em:em_entity_assembly_mol_wt>
</mmcif_em:em_entity_assembly_mol_wtCategory>
Details of the method used to determine the molecular weight.
Scanning Transmission Electron Microscopy Mass Measurement-- PM28
isoforms solubilized in OTG were adsorbed for 1 min to glow discharged
thin carbon films supported by a thick fenestrated carbon layer (directly
after cation-exchange chromatography). The gold-plated copper grids were
then washed on 8 drops of quartz double-distilled water and were
freeze-dried at -80C overnight in the microscope. For mass analysis,
annular dark-field images were recorded in a STEM (VG-HB5) at 80 kV
and doses of 325 +/- 35 electrons/nm2. Digital acquisition of the images
and microscope parameters, system calibration, and mass analysis were
carried out as described previously. The total experimental error was
calculated as the standard error of the mean, plus 5% of the measured
particle mass to account for the absolute calibration uncertainty.
The value (in megadaltons) of the experimentally
determined molecular weight of each component
of the assembly.
The method used to determine the molecular weight.
The value of attribute entity_assembly_id in category em_entity_assembly_mol_wt identifies
a component defined in the EM_ENTITY_ASSEMBLY category. This is a pointer to
attribute id in category em_entity_assembly.
The value of attribute id in category em_entity_assembly_mol_wt must uniquely identify
the molecular weight value provided for each component.
The EM_ENTRY category records a unique identifier for the
data block describing an EM experiment.
The value of attribute id in category em_entry identifies the data block.
Note that this item need not be a number; it can be any unique
identifier.
RDV2
Data items in the em_assembly category record basic information
about the method used to produce the EM map.
based on PDB entry 1DGI
<mmcif_em:em_exptlCategory>
<mmcif_em:em_exptl entry_id="1DGI">
<mmcif_em:reconstruction_method>SINGLE PARTICLE</mmcif_em:reconstruction_method>
<mmcif_em:resolution_published>22.0</mmcif_em:resolution_published>
</mmcif_em:em_exptl>
</mmcif_em:em_exptlCategory>
A description of the method used in the EM experiment
to generate the map.
SINGLE PARTICLE: reconstruction of asymmetric particles or
particles with point symmetry, e.g., ribosome, GroEL,
icosahedral phage
FILAMENT: reconstruction of particles with helical symmetry,
e.g., filamentous phage, helical acetylcholine receptor crystal
2D CRYSTAL: reconstruction of a 2D lattice, e.g., aquoporin
crystal, bacteriorhodopsin crystal
3D CRYSTAL: reconstruction of a 3D lattice, e.g., yeast
peroxisome crystal, acrosomal bundle
INDIVIDUAL STRUCTURE (TOMOGRAM): reconstruction of a single object,
e.g., bacterial cell, desmosomal knot
MULTIPLE SELECTION: multiple methods used.
The author determined highest resolution
of the reconstruction
The author determined lowest resolution
of the reconstruction
The author determined resolution of the reconstruction
This data item is a pointer to attribute id in category entry in the ENTRY category.
Data items in the EM_FSC_CURVE category record the
values for the Fourier Shell Correlation Curve
The x values in the FSC curve
The y values in the FSC curve
attribute curve_id in category em_fsc uniquely identifies a fsc plot
and is a pointer to attribute curve_id in category em_fsc in the
EM_FSC category
This data item uniquely identifies a row
in the FSC curve
Data items in the EM_HELICAL_ENTITY category record details
for a helical or filament type of assembly component.
The angular rotation per helical subunit.
The axial rise per subunit in the helical assembly.
A description of the filament axial symmetry
observed
General details on the filaments studied
The value for the dyad to describe the repeat
parameters for a set of filaments
The value of attribute entity_assembly_id
in category em_helical_entity identifies a particular assembly component.
This data item is a pointer to attribute id
in category entity_assembly in the EM_ENTITY_ASSEMBLY category.
The value of attribute id in category em_helical_entity must uniquely identify
a set of the filament parameters for this assembly component.
Data items in the EM_HELICAL_SELECTION category record details
for the selection of helical or filament particle types.
The numeber of number of helices used
used to refine the repeat parameters
The numeber of unit cells or asymmetric units
used to refine the repeat parameters
The value of attribute selection_id in category em_helical_selection identifies
the general set of selection conditions associated with specific
filament selection conditions described in this category.
The value of attribute selection_id in category em_filament_particle_selection points to
the attribute id in category em_particle_selection in the EM_PARTICLE_SELECTION category.
Data items in the EM_IMAGE_READOUT_CCD category record details
of the CCD readout and parameters for digitization of the image.
Example 1 -
<mmcif_em:em_image_readout_ccdCategory>
<mmcif_em:em_image_readout_ccd image_scanning_id="2">
<mmcif_em:details xsi:nil="true" />
</mmcif_em:em_image_readout_ccd>
</mmcif_em:em_image_readout_ccdCategory>
The detector binning in x direction
The detector binning in y direction
Any additional details about CCD image scanning.
The detector offset in x from the top left corner of the CCD
The detector offset in y from the top left corner of the CCD
The detector read-out speed
The value of attribute id in category em_image_readout_ccd must uniquely identify
a set of CCD image scanning parameters.
This value is a pointer to '_em_image_readout_ccd.id' in
the EM_IMAGE_SCANNING category.
Data items in the EM_IMAGE_SCANNING category record
type of image scanning device used digitized the image.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_image_scanningCategory>
<mmcif_em:em_image_scanning entry_id="1DYL" id="2">
<mmcif_em:type>FILM_SCANNING</mmcif_em:type>
</mmcif_em:em_image_scanning>
</mmcif_em:em_image_scanningCategory>
This data item is a pointer to attribute id
in category citation in the CITATION category.
The type of scanning used in the experiment.
This data item is a pointer to attribute id in category entry in the
ENTRY category.
The value of attribute id in category em_image_scanning must uniquely identify
a particular scanning protocol.
Data items in the EM_IMAGE_SCANNING_FILM category record details
of the film scanning device (microdensitometer)
and parameters for digitization of the image.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_image_scanning_filmCategory>
<mmcif_em:em_image_scanning_film image_scanning_id="2">
<mmcif_em:bits_per_pixel xsi:nil="true" />
<mmcif_em:details xsi:nil="true" />
<mmcif_em:od_range xsi:nil="true" />
<mmcif_em:scanner_model xsi:nil="true" />
<mmcif_em:step_size xsi:nil="true" />
</mmcif_em:em_image_scanning_film>
</mmcif_em:em_image_scanning_filmCategory>
The detector binning in x direction
The detector binning in y direction
The number of bits per pixel used in digitization.
8
Any additional details about scanning film images.
The optical density range (OD=-log 10 transmission).
To the eye OD=1 appears light grey and OD=3 is opaque.
1.4
The film scanner model.
The spot size
The sampling step size (microns) set on the scanner.
The value of attribute id in category em_image_scanning_film must uniquely identify
a set of image scanning parameters.
This value is a pointer to '_em_image_scanning_film.id' in
the EM_IMAGE_SCANNING category.
Data items in the EM_IMAGING category record details about
the parameters used in imaging the sample in the electron microscope.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_imagingCategory>
<mmcif_em:em_imaging entry_id="1DYL" id="1">
<mmcif_em:accelerating_voltage>200</mmcif_em:accelerating_voltage>
<mmcif_em:calibrated_magnification xsi:nil="true" />
<mmcif_em:citation_id>1</mmcif_em:citation_id>
<mmcif_em:details xsi:nil="true" />
<mmcif_em:energy_filter xsi:nil="true" />
<mmcif_em:energy_window xsi:nil="true" />
<mmcif_em:illumination_mode>bright field</mmcif_em:illumination_mode>
<mmcif_em:microscope_id>1</mmcif_em:microscope_id>
<mmcif_em:mode>low dose</mmcif_em:mode>
<mmcif_em:nominal_defocus_max>7600</mmcif_em:nominal_defocus_max>
<mmcif_em:nominal_defocus_min>975</mmcif_em:nominal_defocus_min>
<mmcif_em:nominal_magnification>50000</mmcif_em:nominal_magnification>
<mmcif_em:sample_support_id>1</mmcif_em:sample_support_id>
<mmcif_em:specimen_holder_model>gatan 626-0300</mmcif_em:specimen_holder_model>
<mmcif_em:temperature>95</mmcif_em:temperature>
<mmcif_em:tilt_angle_max>0</mmcif_em:tilt_angle_max>
<mmcif_em:tilt_angle_min>0</mmcif_em:tilt_angle_min>
</mmcif_em:em_imaging>
</mmcif_em:em_imagingCategory>
A value of accelerating voltage (in kV) used for imaging.
300
The magnification value obtained for a known standard just
prior to, during or just after the imaging experiment.
61200
The method used to determine the calibrated magnification.
This data item is a pointer to attribute id in category citation in
the CITATION category.
The details about the condenser aperture used including dimension,
material, and treatment.
Any additional imaging details.
Tilt series for tomographic reconstruction was recorded
over a 124 degree angular range, using a 2 degree angular
interval, with a high voltage electron microscope.
Acceleration voltage = 1.0 MV. Em = AEI.
Alignment using gold markers and cross-correlation.
Reconstruction technique: Modified back-projection.
Direction of missing wedge:
1
All image processing steps described below were performed using the
Semper image processing system(Synoptics Ltd., Cambridge, United Kingdom).
2
The value of attribute detector_id in category em_imaging must uniquely identify
the type of detector used in the experiment.
The camera length (in millimetres). The camera length is the
product of the objective focal length and the combined magnification
of the intermediate and projector lenses when the microscope is
operated in the diffraction mode.
The method used to determine the electron dose received by the specimen.
The electron dose range received by the specimen
(electrons per square angstrom).
0.9 - 1.1
The type of energy filter spectrometer apparatus.
FEI
The energy filter range in electron volts (eV)set by spectrometer.
0 - 15
The mode of illumination.
The value of attribute image_scans_id in category em_imaging identifies
the scanning protocol used in the experiment.
The item is a pointer to attribute id in category em_image_scanning in category
EM_IMAGE_SCANNING.
The imaging cryogen used
A pointer to attribute id in category em_microscope in the EM_MICROSCOPE category
The mode of imaging.
The maximum defocus value of the objective lens (in nanometres) used
to obtain the recorded images.
7600
The minimum defocus value of the objective lens (in nanometres) used
to obtain the recorded images.
975
The magnification indicated by the microscope readout.
60000
Description of the objective aperture used including the dimension,
material, and treatment.
This data item is a pointer to attribute id in category em_sample_support in
the EM_SAMPLE_SUPPORT category.
Description of the selective aperture used
The name of the model of specimen holder used during imaging.
Description of the spot size as determined by the setting of the first
condenser lens.
The mean specimen stage temperature (degrees Kelvin) during imaging
in the microscope.
The maximum angle at which the specimen was tilted to obtain
recorded images.
60
The minimum angle at which the specimen was tilted to obtain
recorded images.
0
This data item is a pointer to attribute id in category entry in the ENTRY category.
The value of attribute id in category em_imaging must uniquely identify
each imaging experiment.
Data items in the EM_MAP category record details
about the type of the 3d-em map. The map is represented
logically as a three-dimensional array of data-values
of the same data-type. To interpret the contents of of a 3d-map file
it is necessary to know the data-type of the array and the size of the
array in three dimensions (i.e.the number of columns, rows and sections).
In a 1d-array representation columns are the fastest changing, followed by
rows and sections. The first element of the array will have index 0.
The 3d-em map is in a defined orientation/position in Universal 3D Space.
This space is described by a right-handed cartesian coordinate system
(and is the same coordinate system as that used for structures deposited
in the PDB).
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_mapCategory>
<mmcif_em:em_map entry_id="EM9999" id="1">
<mmcif_em:details xsi:nil="true" />
<mmcif_em:num_columns>100</mmcif_em:num_columns>
<mmcif_em:num_rows>100</mmcif_em:num_rows>
<mmcif_em:num_sections>100</mmcif_em:num_sections>
<mmcif_em:value_density_max xsi:nil="true" />
<mmcif_em:value_density_mean xsi:nil="true" />
<mmcif_em:value_density_min xsi:nil="true" />
</mmcif_em:em_map>
</mmcif_em:em_mapCategory>
This data item is a pointer to the 2D_CRYSTAL_GROW category.
This data item is a pointer to the 3D_RECONSTRUCTION category.
The author_threshold for isosurface_countour_level for the map
The map axis order fast
The map axis order fast
The map axis order slow
Value of unit cell angle alpha in degrees.
Value of unit cell angle beta in degrees.
Value of unit cell angle gamma in degrees.
Unit cell length a.
Error standard deviation of unit cell length a.
Unit cell length b.
Error standard deviation of unit cell length b.
Unit cell length c.
Error standard deviation of unit cell length c.
The limit in column size
The contrast convention used for the map
The map data_type describes the types of data in the map.
Mode defines the data structure on disc.
Mode 0=integer*1;mode 1=integer*2;mode 2=real*4. Mode 2 is the normal
mode used in CCP4 programs.
Any additional details about the map.
Description of any enforced symmetry present in the map
The method used to determine the hand of the virus.
The hand is fixed for the reconstruction by combining the
projections in a consistent way. Information gleaned from
pairs of images of tilted particles must be used to validate a
particular choice of hand.
This data item is a pointer to the IMAGING category.
The isosurface_countour_level for the map
Description of any local symmetry present in the map
Pointer to the MAP_EIGENVALUES category.
This data item is a pointer to the MAP_FILES category.
This data item is a pointer to the MAP_STRUCTURE_FACTORS category.
This data item is a pointer to the EM_SYMMETRY category.
The number of atoms.
The number of class averages (one class average contains
images that are the same) resulting from the multivariate statistical
analysis of the individual images of particles are 2d projections
of a 3d structure in different projection directions. Given a
sufficiently large number of good 2d projections the 3d structure
can be reconstructed knowing the orientational relationship
between all the projection class averages. For an entirely asymmetric
particle at least three different projections are required to solve
the orientation problem.
The number of columns of the map.
The number of observations.
The number of rows of the map.
The number of sections of the map.
The number of unique electron reflections collected.
The x origin of the map.
The y origin of the map.
The z origin of the map.
The percentage of possible reflections collected to specified resolution.
The method used to determine the phase origin of the virus map.
The x pixel size
The y pixel size
The z pixel size
Description of any plane group present
The R-free statistic value measures the agreement between the atomic
model and the diffraction data for a 'test' set of reflections (usually
10%) that is omitted during refinement.
The R-factor value compares overall agreement between the amplitudes
of two sets of structure factors as follows:
R= sigma || Fobs | - | Fcalc || / sigma | Fobs |
For each reflection the magnitude of the computed difference between
the observed structure-factor amplitude from the native data
set |Fobs| and the calculated amplitude from the model in its current
trial location |Fcalc| is summed for all reflections and divided by
the sum of the observed structure factors.
Wavelength of electrons in angstroms.
Date (YYYY-MM-DD) of map release
2001-05-08
The limit in row size
The limit in section size
The space group number for the map
The length of the x interval in microns.
The length of the y interval in microns.
The length of the z interval in microns.
for 2d crystals the thickness
Maximum density value in the map.
Mean (average) density value of the map.
Minimum density value in the map.
The standard deviation density value of the map.
This data item is a pointer to the ENTRY category.
Unique identifier of the volume map.
Data items in the EM_MAP_CTF_CORRECTION category record details
about the CTF correction method.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_map_ctf_correctionCategory>
<mmcif_em:em_map_ctf_correction id="1" map_id="1">
<mmcif_em:details xsi:nil="true" />
<mmcif_em:method xsi:nil="true" />
</mmcif_em:em_map_ctf_correction>
</mmcif_em:em_map_ctf_correctionCategory>
Any additional details about ctf correction.
The method used to correct for the image distortions introduced
by the phase contrast transfer function (CTF). CTF correction
could be applied to the entire scanned micrograph or alternatively
they may be applied to the extracted images of individual particles
or at the end of the analysis to the density map reconstructed
from the micrograph.
Unique identifier for CTF correction of the map.
This data item is a pointer to the EM_MAP category.
Data items in the EM_MAP_EIGENVALUES category record details
about values of the eigenvectors for projection sets.
2d projection images are considered as a linear combination of
the main eigenvectors 'eigenimages' of the projection set,
enabling a reduction of the total amount of data and simplifying
its interpretation. The eigenvalue spectrum gives an indication
of the randomness of the data that is included in the reconstruction.
The completeness of the data can be verified eg all eigenvalues exceeded 1.0.
Example 1 -
<mmcif_em:em_map_eigenvaluesCategory>
<mmcif_em:em_map_eigenvalues id="1" map_id="1">
<mmcif_em:details xsi:nil="true" />
<mmcif_em:max_value xsi:nil="true" />
<mmcif_em:min_value xsi:nil="true" />
<mmcif_em:spectrum xsi:nil="true" />
</mmcif_em:em_map_eigenvalues>
</mmcif_em:em_map_eigenvaluesCategory>
Any additional details about the eigenvalues.
The maximum eigenvalue. A low inverse eigenvalue indicates that many,
well-spaced samples have been averaged to generate the coefficient
while a high one indicates that only a few sample points were used
so that the coefficient is more susceptible to noise.
The minimum eigenvalue. A low inverse eigenvalue indicates that many,
well-spaced samples have been averaged to generate the coefficient
while a high one indicates that only a few sample points were used
so that the coefficient is more susceptible to noise.
A description of the eigenvalue spectrum for the data set used in the 3d
reconstruction for the map. A data set consisting of pure noise has a
characteristic eigenvalue spectrum which depends on the number of images,
the number of image elements and the noise statistics.
Since the eigenvalues are only determined by the spacing and number of
the sample points, the eigenvalue spectrum is not affected by the signal
to noise in the data or the reliability of the orientations. This
information is seen from the resolution dependence of the phase residual
seen during refinement.
For the eigenvectors to be significant, the associated eigenvalues should
stand out from the noise eigenvalue spectrum.
Unique identifier of the EIGENVALUES category.
This data item is a pointer to the EM_MAP category.
Data items in the EM_MAP_FIGURE record details
about figures associated with the map. These can consist
of figures with associated text which are related to the map.
Example 1 -
<mmcif_em:em_map_figureCategory>
<mmcif_em:em_map_figure id="1" map_id="1">
<mmcif_em:details xsi:nil="true" />
<mmcif_em:map_files_id>file1</mmcif_em:map_files_id>
<mmcif_em:num_bytes>1000</mmcif_em:num_bytes>
</mmcif_em:em_map_figure>
</mmcif_em:em_map_figureCategory>
Any additional details about the figure uploaded with the map.
These could include captions.
Unique identifier of the figure assembly.
The number of bytes in the image file.
Unique identifier of the figure assembly.
This data item is a pointer to the EM_MAP category.
Data items in the EM_MAP_FILES category record details
about files relating to the map. These files can be
uploaded and include files containing information
about
Example 1 -
<mmcif_em:em_map_filesCategory>
<mmcif_em:em_map_files id="1" map_id="1">
<mmcif_em:details xsi:nil="true" />
</mmcif_em:em_map_files>
</mmcif_em:em_map_filesCategory>
Any additional details about the files.
The orthogonal slices x_slice file identifier.
The orthogonal slices y_slice file identifier.
The orthogonal slices z_slice file identifier.
Unique identifier of the MAP_FILES category.
This data item is a pointer to the EM_MAP category.
Data items in the EM_MAP_RESOLUTION category record details
about the Fourier Shell Correlation
The most popular method at the moment for resolution assessment is the
Fourier Shell Correlation, although there is no standard way to define
the cutoff value. It assumes a uniform distribution of the resolution
along the three-dimensions (so there is a single value of resolution).
The Fourier Shell Correlation curve is defined as a list of value pairs
(x, y) where x is the spatial frequency (or inverse resolution in 1/A)
and y is the correlation coefficient (a value between 0 and 1).
Example 1
<mmcif_em:em_map_resolutionCategory>
<mmcif_em:em_map_resolution entry_id="EM9999">
<mmcif_em:title>ACh receptor FSC Plot</mmcif_em:title>
<mmcif_em:x_axis>Resolution (A-1)</mmcif_em:x_axis>
<mmcif_em:y_axis>Correlation Coefficient</mmcif_em:y_axis>
</mmcif_em:em_map_resolution>
</mmcif_em:em_map_resolutionCategory>
Method used to determine the resolution of the map. The first of the
two fundamentally different methods is one that relies on dividing the
the data into two halves and then calculating two independent
reconstructions which are then compared by Fourier Shell Correlation
(FSC) or differential phase residual (DPR). The second different method
of assessing resolution is more relevant where there is a combination of EM
and X-ray data. The similarity between the EM density and the electron
density corresponding to the atomic structure can be used to determine
the resolution of the EM map.
attribute curve_id in category em_map_resolution uniquely identifies a fsc plot
The cutoff value to estimate the resolution value can be defined by:
- the point of the curve where the correlation is 0.5
- the point of the curve that crosses a significance threshold curve
According to Orlova et al. 1997 (J Mol Biol, 271:417) this significance
threshold curve is defined as the 3*sigma (sigma = standard deviation of
the FSC) for non-symmetrical particles. (units: 1/A)
[stc stands for significance threshold curve]
Any additional details about the resolution determination method.
The value of the differential phase residual criterion.
The two dimensional differential phase residual spatial frequency value.
The differential phase residual value.
The value of the fourier shell correlation criterion.
A more accurate measure of the resolution is obtained by multiplying
the sigma threshold value by the square root of the number of
asymmetric units within the given point group symmetry. Reference:
(Orlova et al, J mol Biol, 271, 417-437,1997).
The fourier shell correlation significance threshold in sigma.
e.g. a 3 sigma threshold is three standard deviations over
the random noise value.
The fourier shell correlation spatial frequency value.
_em_map_resolution.map_id is a pointer to _em_map.id in the EM_MAP category
The Nyquist frequency is double the sampling step. e.g. for data
sampled at 5 angstroms the Nyquist frequency is 1/10 angstroms.
It is important to have the sampling rate of the data high enough
so that the image information stays sufficiently away from the
Nyquist frequency, otherwise there is a danger that the high-
resolution information in both of the reconstruction volumes
may be correlated.
The cut-off criteria used in the resolution determination.e.g an FSC
limit of 0.5 is used as a conservative measure of resolution.
the curve has to be weigthed taking into the account the number of
independent asymmetric units (N). In that case the curve would be
defined as sqrt(N)*3*sigma. This is the weighted factor used.
If this weighted factor is always defined as 3*sqrt(N) then we only
need to know the number of independent units N.
The spectral-signal-to-noise ratio value.
This two-dimensional resolution determination method compares reprojections.
The title of the FSC graph - equivalent to the
name of the assembly of observed complexes.
The title of the x_axis in the FSC graph
Usually the resolution in reciprical Angstroms
may be spatial_frequency
The title of the y_axis in the FSC graph
The Correlation coefficient
or sigma_value
This data item is a pointer to attribute id
in category entry in the ENTRY category.
Data items in the EM_MAP_STRUCTURE_FACTORS category record details
about structure factors relating to the map. These are uploaded
in a file.
Example 1 -
<mmcif_em:em_map_structure_factorsCategory>
<mmcif_em:em_map_structure_factors id="1" map_id="1">
<mmcif_em:details xsi:nil="true" />
<mmcif_em:method xsi:nil="true" />
</mmcif_em:em_map_structure_factors>
</mmcif_em:em_map_structure_factorsCategory>
Any additional details about the structure factors file.
Pointer to the MAP_FILES category.
A description of how the structure factors of the
masked cryo-EM maps were calculated.
For example structure factors could be calculated by
Fourier transformation using the progrma SFALL of the
CCP4 package.
Unique identifier of the map structure factors.
This data item is a pointer to the MAP category.
Data items in the EM_MAP_SURFACE_RENDERING category record details
about surface rendering of the map. The surface of the map has to
be defined and 'rendered' to make understandable images. The quality
of the structure can be judged visually by looking at the high-resolution
texture of the molecular surface. It can make sense to threshold/interpret
data to 100% (or up to 120%) of the expected volume of the molecular assembly
which has been calculated from the molecular mass. To emphasize the fine
structures in the map thresholding values as little as 25% may be used.
Example 1 -
<mmcif_em:em_map_surface_renderingCategory>
<mmcif_em:em_map_surface_rendering id="1" map_id="1">
<mmcif_em:details xsi:nil="true" />
<mmcif_em:map_files_id>file1</mmcif_em:map_files_id>
<mmcif_em:method xsi:nil="true" />
<mmcif_em:threshold_volume_mol_wt xsi:nil="true" />
</mmcif_em:em_map_surface_rendering>
</mmcif_em:em_map_surface_renderingCategory>
Any additional details about the surface rendered image.
This data item is a pointer to the EM_FILES category.
The method used to obtain the surface rendered image.
The threshold volume molecular weight (as a percentage) used to
produce the surface rendered image.
Unique identifier of the surface rendered image figure of the assembly.
This data item is a pointer to the EM_MAP category.
Data items in the EM_MAP_SYMMETRY category record details
about the symmetry of the assembly in the map.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_map_symmetryCategory>
<mmcif_em:em_map_symmetry map_id="1">
<mmcif_em:enforced_symmetry xsi:nil="true" />
<mmcif_em:equiv_pos_as_xyz xsi:nil="true" />
<mmcif_em:id>1</mmcif_em:id>
<mmcif_em:plane_group_name_H-M xsi:nil="true" />
</mmcif_em:em_map_symmetry>
</mmcif_em:em_map_symmetryCategory>
This is the enforced symmetry applied to the map.
This is an equivalent xyz position.
Unique identifier of the map symmetry.
This is the plane group described using Herman Maugin nomenclature.
This data item is a pointer the MAP category.
Data items in the EM_MICROGRAPHS category record details
about em raw data images
The amplitude contrast e.g. 0.06
Astigmatism(axial): an electron-optical lens aberration that causes
the defocus to be a function of azimuth, and the contrast transfer
function to deviate from circular symmetry about the optical axis.
As a consequence, the Thon rings deform into elliptic or hyperbolic
patterns, depending on the size of defocus and the size of the
astigmatic defocus difference.
A flag for Y or N for astigmatism estimation
The astigmatism ratio e.g. 0.96
For each micrograph smaller images are cropped from the
image with the power spectrum found for all small images
and they are averaged to improve signal to noise ratio.
A flag for Y or N for circular averaging
The difference between the two is that in Phase only correction
only the phase of the CTF is flipped whereas in Phase and Amplitude
correction, Wiener filtering is done to correct both phase and
amplitude. If the envelope function and noise spectrum parameters
are not available then phase only correction is recommended.
For example if the parameters calculated from far from focus images
are used to correct near to focus images (after adjusting for the
defocus difference), the envelope function and noise spectrum
parameter estimates of far from focus images are not reliable for
near to focus images.
The threshold set for edge detection for carbon and ice images.
parameters of the CTF used for correcting are estimated
from each image
or
parameters estimated for the far from images are used to
correct near to focus images after compensating for the defocus
The exposure time in micro-seconds
The exposure type
Field size refers to the width of each small image cropped.
An attribute averaging_overlap in category em_micrographs implies that the
successive images have an overalp of
(1-_em_micrographs.averaging_overlap)*field size.
A higher value of attribute averaging_overlap in category em_micrographs means
a greater number of smaller images are used for averaging.
If the signal to noise ratio is very low, the averaging overlap
should be changed for better estimate of power spectrum.
The type of image filter used
This data item is a pointer to attribute id
in category em_microscope in the EM_MICROSCOPE category.
The nominal defocus e.g. 2.00
The upper cutoff frequency
The refined defocus estimate e.g. 1.975
This data item is a pointer to attribute id
in category em_sample_preparation in the EM_SAMPLE_PREPARATION category.
This data item is a pointer to attribute id in category entry in the ENTRY category.
The value of attribute image_id in category em_micrograph must uniquely identify
an image used in the em experiments.
Data items in the EM_MICROSCOPE category record details
about the microscope
The source of electrons. The electron gun.
The microscope model
The spherical aberration coefficient (Cs) in millimetres,
of the objective lens.
1.4
The value of attribute id in category em_microscope must uniquely identify
a microscope used in the em experiments.
Data items in the EM_ORTHOGONAL_SLICES category record
details about orthogonal slices through the map. These consist
of an x-slice, y-slice and z-slice through the map.
Example 1 -
<mmcif_em:em_orthogonal_slicesCategory>
<mmcif_em:em_orthogonal_slices map_id="1">
<mmcif_em:id>1</mmcif_em:id>
<mmcif_em:x_slice_id>1</mmcif_em:x_slice_id>
<mmcif_em:x_slice_number>1</mmcif_em:x_slice_number>
<mmcif_em:y_slice_id>1</mmcif_em:y_slice_id>
<mmcif_em:y_slice_number>1</mmcif_em:y_slice_number>
<mmcif_em:z_slice_id>1</mmcif_em:z_slice_id>
<mmcif_em:z_slice_number>1</mmcif_em:z_slice_number>
</mmcif_em:em_orthogonal_slices>
</mmcif_em:em_orthogonal_slicesCategory>
This data item is a unique identifier for the ORTHOGONAL_SLICES category.
The orthogonal x slice id.
The orthogonal x slice number.
The orthogonal y slice id.
The orthogonal y slice number.
The orthogonal z slice id.
The orthogonal z slice number.
This data item is a pointer to the MAP category.
Data items in the EM_PARTICLE_SELECTION category record details
about the method to pick select from the raw micrographs.
The particle picking centering method
The so-called center of gravity method where the image is scanned and
the intensity peaks calculated to find the center of the particle 'mass'.
The image is then shifted by the correct amounts to maximize the number
of peaks near the center.
Another centering method averages all the picked particles together, and
then cross correlates each individual particle to the average. The cross
correlation function is used to determine by how much to shift each particle
when trying to center it. When all the particles have been cross correlated
to the average and shifted, a new average is generated. Once again, all the
particles are compared to the new average, and shifted as necessary to
center them as best as possible. This iterative process is repeated until no
significant shift is necessary for all the particles Crosscorrelating to a
global average is but one variation on this theme. Similar methods also use
an external model or a rotational average of the particle itself as the
centering reference. Unfortunately, it can be difficult to obtain a
reasonable external refernce, so a global average or a rotational average
are most often used.
This data item is a pointer to attribute id in category citation in the
CITATION category.
Maxima having correlation scores below this threshold are
not considered as possible particle locations.
General details on the particle picking method
Particles were picked using a program written in-house for selecting
filaments. Lines are drawn over the filaments using the computer mouse,
and the program selects coordinates for boxing the particles at a
user-selected interval while keeping track of groups of particles
coming from the same filament. This is useful where polarity can be
determined per filament by two-dimensional averaging. The program also
keeps track of the angle of the overlaid, user-drawn line, which is
used for preliminary vertical orientation of the particles.
8440 particles of 80 x 80 pixel size were selected from the filaments.
1
A reference was established by selecting a well preserved particle
and symmetrizing it 20-fold rotationally. Cross-correlation functions
of this reference with images of digitized micrographs containing
adsorbed particles of PM28 revealed correlation peaks at the particle
positions, irrespective of their angular orientation. Using this
particle picking method a gallery of 4096 particles was created.
2
Minimum difference between a peak and its surrounding trough in
the correlation score.
Radius used to test if a point's correlation score is locally maximal.
Maximium radius of the peaks in the correlation score.
The particle picking method
Minimum radius of the peaks in the correlation score.
Description of the pre-processing filters used
The value of attribute entity_assembly_id in category em_particle_selection identifies
assembly or assembly component associated with this set of
selection conditions.
This data item is a pointer to attribute id
in category em_entity_assembly in the EM_ENTITY_ASSEMBLY category.
The value of attribute id in category em_particle_selection uniquely identifies a
set of selection conditions for this entity.
Data items in the EM_SAMPLE_PREPARATION category
record details of sample conditions prior to loading
onto grid support.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_sample_preparationCategory>
<mmcif_em:em_sample_preparation id="1">
<mmcif_em:array_formation_id xsi:nil="true" />
<mmcif_em:entity_assembly_id>1</mmcif_em:entity_assembly_id>
<mmcif_em:pH>7.6</mmcif_em:pH>
<mmcif_em:sample_concentration>5</mmcif_em:sample_concentration>
<mmcif_em:solution_id>1</mmcif_em:solution_id>
</mmcif_em:em_sample_preparation>
</mmcif_em:em_sample_preparationCategory>
This data item is a pointer to attribute id
in category em_array_formation in the ARRAY_FORMATION category.
Details on the sample preparation
Selectively stained by injection of horseradish peroxidase,
embedded in Spurr's resin and cut into 2-3 um thick sections.
1
Enzyme Preparations. S. cerevisiae PDC was purified to near homogeneity
from baker's yeast by modification of a published procedure. Highly
purified E1 was obtained by resolution of PDC with 2 M NaCl at pH 7.3
followed by FPLC on a Superdex 200 column. The weight-average molecular
weight of the PDC was determined by light scattering measurement to be
~8 x 106. On the basis of the known molecular weight of the complex and
its component enzymes and the experimentally determined polypeptide chain
ratios of E2/BP/E3, we estimated that the subunit composition of the
S. cerevisiae PDC is ~24 E1 tetramers, 60 E2 monomers, 12 BP monomers,
and 8 E3 dimers. Sufficient E1 was added to a sample of the PDC
preparation to increase the molar ratio of E1/E2 core to 60:1.
This product is designated larger PDC or ~60 E1/E2 core PDC
2
embedment in vitreous ice.
3
Detergent-solubilized particles eluted from the cation-exchange
column were directly adsorbed for 1 min to parlodion carbon-coated
copper grids rendered hydrophilic by glow discharge at low pressure
in air. Grids were washed with 4 drops of double-distilled water
and stained with 2 drops of 0.75% uranyl formate. Images were recorded
on Eastman Kodak Co. SO-163 sheet film with a Hitachi H-7000
electron microscope operated at 100 kV. Electron micrographs of
single particles adsorbed to the carbon film were digitized using
a Leafscan-45 scanner (Leaf Systems, Inc., Westborough, MA).
4
This data item is a pointer to attribute id in category entity_assembly in the
entity_assembly category.
The pH value of the observed sample buffer.
The value of the concentration (mg/mL for mg per milliliter)
of the complex in the sample.
This data item is a pointer to attribute id in category em_solution_composition in the
EM_SOLUTION_COMPOSITION category.
This data item is a pointer to attribute id
in category em_sample_support in the EM_SAMPLE_SUPPORT category.
The value of attribute id in category em_sample_preparation must
uniquely identify the sample preparation.
Data items in the EM_SAMPLE_SUPPORT category record details
of the electron microscope grid type, grid support film and pretreatment
of whole before sample is applied
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_sample_supportCategory>
<mmcif_em:em_sample_support id="1">
<mmcif_em:citation_id>2</mmcif_em:citation_id>
<mmcif_em:details xsi:nil="true" />
<mmcif_em:film_material>HOLEY CARBON</mmcif_em:film_material>
<mmcif_em:grid_material>COPPER</mmcif_em:grid_material>
<mmcif_em:grid_mesh_size>400</mmcif_em:grid_mesh_size>
<mmcif_em:grid_type>MESH</mmcif_em:grid_type>
<mmcif_em:method xsi:nil="true" />
<mmcif_em:pretreatment>GLOW DISCHARGE</mmcif_em:pretreatment>
</mmcif_em:em_sample_support>
</mmcif_em:em_sample_supportCategory>
This data item is a pointer to attribute id
in category citation in the CITATION category.
A description of any additional details concerning the sample support.
This grid plus sample was kept at -170 deg C for a month before use
1
A 3-microliter sample of each PDC preparation (~0.35 mg/ml containing
20 microgram/ml bacitracin) was deposited, blotted, and quick-frozen
in liquid ethane on a glow-discharged carbon-coated holey grid.
The vitrified samples were recorded at ~1 micrometer under focus at
~10 e/Angstroms-squared dose for image processing. A second exposure
of ~2-3 micrometer under focus was recorded and used as an aid
in analyzing the images with the focal pair method. The images were
recorded on Kodak SO 163 film at a nominal magnification of x50,000
in a JEOL JEM 1200 electron microscope operated at 100 kV.
2
Orientation of 4300 Ribosome projections identified by 3D projection
matching using low resolution reference. (Penczek et al., 1994).
Reconstruction (SIRT) simultaneously performed CTF correction
(Zhu et al. submitted).
3
The support material covering the em grid.
The name of the material from which the grid is made.
The value of the mesh size (per inch) of the em grid.
400
A description of the grid type.
A description of the method used to produce the support film.
1% formvar in chloroform cast on distilled water
A description of the grid plus support film pretreatment.
glow-discharged for 30 sec in argon
The value of attribute id in category em_sample_support must uniquely identify
the sample support.
Data items in the EM_SINGLE_PARTICLE_ENTITY category record details
for a single particle assembly component.
Additional details describing the single particle
The point group symmetry of the single particle
n value for circular and dihedral
point group symmetries (n > 8).
The value of attribute entity_assembly_id in category em_single_particle_entity identifies
a particular assembly component.
This data item is a pointer to attribute id in category em_entity_assembly in the
EM_ENTITY_ASSEMBLY category.
The value of attribute id in category em_single_particle_entity must uniquely identify
a set of the single particle parameters for this assembly component.
Data items in the EM_SINGLE_PARTICLE_SELECTION category
record details of images from scanned micrographs and the
number of particles selected from a scanned set of micrographs.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_single_particle_selectionCategory>
<mmcif_em:em_single_particle_selection selection_id="1">
<mmcif_em:citation_id>1</mmcif_em:citation_id>
<mmcif_em:details xsi:nil="true" />
<mmcif_em:method>INTERACTIVE</mmcif_em:method>
</mmcif_em:em_single_particle_selection>
</mmcif_em:em_single_particle_selectionCategory>
This data item is a pointer to attribute id in category citation in the
CITATION category.
Any additional details used for selecting observed assemblies.
negative monitor contrast facilitated particle picking
The method used for selecting observed assemblies.
particles picked interactively from monitor
The number of micrographs used
The number of particles selected from the projection set of images.
840
The protocol used for selecting observed assemblies.
The value of attribute selection_id in category em_single_particle_selection identifies
the general set of selection conditions associated with specific
single particle selection conditions described in this category.
The value of attribute selection_id in category em_single_particle_selection points to
the attribute id in category em_particle_selection in the EM_PARTICLE_SELECTION category.
Data items in the EM_SOLUTION_COMPOSITION category
record details of the sample buffer.
Any additional details to do with buffer.
aerated
The name of the buffer.
Acetic acid
The pH of the buffer.
6.93
The value of attribute id in category em_solution_composition must
uniquely identify the sample solution conditions.
Data items in the EM_STAIN category record details
about the staining techniques used.
Text describing a reference citation
on the staining techniques used
General details on the staining techniques used
The humidity at which the staining technique was used
Text describing the protocol for the staining techniques used
A pointer to attribute id in category em_sample_preparation in the
EM_SAMPLE_PREPARATION category
The staining technique temperature used
Text giving details on the time factors
involved in the staining techniques used
The general class or type of the staining technique
used
This data item is a pointer to attribute id
in category entry in the ENTRY category.
The value of attribute id in category em_stain must uniquely identify
set of stain parameters
Electron tomography allows the structural organisation of individual
cells and organelles and bacterial cells to be studied at nanometre
resolution. The samples are unique objects which precludes averaging
over many copies so that tomograms are built from images of a tilt
series taken from a single copy of the object.
the StagePosition in X
the StagePosition in Y
General details on the tomographic experiment
This data item is a pointer to attribute id in category entry in the ENTRY category.
Number of sections used in reconstruction of tomographic map.
Tilt angle increment in (degrees) used in reconstruction of
tomographic map.
The value of attribute id in category em_tomography must uniquely identify
a collection of observed complexes.
Data items in the EM_TOMOGRAPHY_IMAGE category
record details of each of the images collected
The defocus used for each image
The electron_dose used for each image
This data item is a pointer to attribute id in category entry in the ENTRY category.
The exposure_time used for each image
The magnification used for each image
The pixel_size used for each image
The shift in x used for each image
The shift in y used for each image
The tilt_angle used for each image
The value of attribute id in category em_tomography_image must uniquely identify
each tilted image
Data items in the EM_VIRUS_ENTITY category record details
of a virus component.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_virus_entityCategory>
<mmcif_em:em_virus_entity entity_assembly_id="1" id="1">
<mmcif_em:empty>NO</mmcif_em:empty>
<mmcif_em:enveloped>YES</mmcif_em:enveloped>
<mmcif_em:ictvdb_id>00.073.0.01.023</mmcif_em:ictvdb_id>
<mmcif_em:virus_host_category>VERTERBRATES</mmcif_em:virus_host_category>
<mmcif_em:virus_host_species>HOMO SAPIENS</mmcif_em:virus_host_species>
<mmcif_em:virus_isolate>STRAIN</mmcif_em:virus_isolate>
<mmcif_em:virus_type>VIRUS</mmcif_em:virus_type>
</mmcif_em:em_virus_entity>
</mmcif_em:em_virus_entityCategory>
Flag to indicate if the virus is empty or not.
Flag to indicate if the virus is enveloped or not.
The International Committee on Taxonomy of Viruses
(ICTV) Taxon Identifier is the Virus Code used throughout the
ICTV database (ICTVdb). The ICTVdb id is the appropriate
identifier used by the International Committee on Taxonomy of Viruses
Resource. Reference: Virus Taxonomy, Academic Press (1999).
ISBN:0123702003.
http://www.ncbi.nlm.nih.gov/ICTVdb/
01.0.2.0.001
01.0.2.0.002
The host category description for the virus.
The host cell from which the virus was isolated.
HELA
CHO
The host species from which the virus was isolated.
homo sapiens
gallus gallus
The isolate from which the virus was obtained.
STRAIN HIV-1
SEROTYPE A
The type of virus.
The value of attribute entity_assembly_id in category em_virus_entity identifies
a particular assembly component.
This data item is a pointer to attribute id in category em_entity_assembly in the
EM_ENTITY_ASSEMBLY category.
The value of attribute id in category em_virus_entity must uniquely identify
a set of the filament parameters for this assembly component.
Data items in the EM_VIRUS_SHELLS category record details
of the viral shell number, diameter of each shell and triangulation
number of an icoshedral virus.
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_virus_shellsCategory>
<mmcif_em:em_virus_shells id="1" virus_entity_id="1">
<mmcif_em:shell_diameter>400</mmcif_em:shell_diameter>
<mmcif_em:triangulation_num>4</mmcif_em:triangulation_num>
</mmcif_em:em_virus_shells>
</mmcif_em:em_virus_shellsCategory>
The value of the diameter (in angstroms) for each
protein shell of the virus.
The triangulation number (T number) refers to the organisation
of the virus geometry. figure.
It is given by the following relationship:
T= h*2 + hk +k*2, where h and k are positive integers that
define the position of the five-fold vertex on the original
hexagonal net.
4
131
1
The value of attribute id in category em_em_virus_shells must uniquely identify
the number and diameter of each virus protein shell and its
triangulation number.
The value of attribute virus_entity_id in category em_virus_shells is
a pointer to attribute id in category em_virus_entity in the VIRUS_ENTITY
category.
Data items in the EM_VITRIFICATION category
record details about the method and cryogen used in
rapid freezing of the sample on the grid prior to its
insertion in the electron microscope
Example 1 - based on PDB entry 1DYL and laboratory records for the
structure corresponding to PDB entry 1DYL
<mmcif_em:em_vitrificationCategory>
<mmcif_em:em_vitrification entry_id="1DYL" id="1">
<mmcif_em:citation_id>1</mmcif_em:citation_id>
<mmcif_em:cryogen_name>ETHANE</mmcif_em:cryogen_name>
<mmcif_em:details> SAMPLES WERE PREPARED AS THIN
LAYERS OF VITREOUS ICE AND
MAINTAINED AT NEAR LIQUID NITROGEN
TEMPERATURE IN THE ELECTRON MICROSCOPE
WITH A GATAN 626-0300 CRYOTRANSFER
HOLDER. </mmcif_em:details>
<mmcif_em:humidity>90</mmcif_em:humidity>
<mmcif_em:instrument xsi:nil="true" />
<mmcif_em:protocol>PLUNGE VITRIFICATION</mmcif_em:protocol>
<mmcif_em:sample_preparation_id>1</mmcif_em:sample_preparation_id>
<mmcif_em:temp>95</mmcif_em:temp>
<mmcif_em:time_resolved_state xsi:nil="true" />
</mmcif_em:em_vitrification>
</mmcif_em:em_vitrificationCategory>
This data item is a pointer to attribute id in category citation in the
CITATION category.
This is the name of the cryogen.
Any additional details relating to vitrification.
argon atmosphere
The humidity (%) in the vicinity of the vitrification process.
90
The type of instrument used in the vitrification process.
The procedure for vitrification.
blot for 2 seconds before plunging
This data item is a pointer to attribute id in category em_sample_preparation in the
EM_SAMPLE_PREPARATION category.
The temperature (in degrees Kelvin) at which vitrification took place.
4.2
The length of time after an event effecting the sample that
vitrification was induced and a description of the event.
30 msec after spraying with effector'
This data item is a pointer to attribute id in category entry in the ENTRY category.
The value of attribute id in category em_vitrification must uniquely identify
the vitrification procedure.