Contacts of the helix formed by residues 293 - 317 (chain A) in PDB entry 2GPV


Residue contacts within the protein are derived with the CSU software (Sobolev V., Sorokine A., Prilusky J., Abola E.E. and Edelman M. (1999) Automated analysis of interatomic contacts in proteins. Bioinformatics, 15, 327-332). A short description of the analytical approach is given at the end of the page.
For CSU analysis of other PDB entry

Note:
Non-standard 3 letter residue codes indicate a heterogroup. To identify and analyse, use LPC software

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with SER 293 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    291A  THR      3.9     1.0    +      -       -      -
    292A  LEU*     1.3    75.8    -      -       -      +
    294A  LEU*     1.3    65.9    +      -       -      +
    295A  ALA*     4.2     2.5    -      -       -      -
    296A  ASP*     3.0    22.9    +      -       -      +
    297A  GLN*     3.0    20.1    +      -       -      +
    383A  GLU*     2.7    29.5    +      -       -      +
    384A  ASP*     5.8     0.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 294 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    292A  LEU      3.7     1.0    +      -       -      +
    293A  SER*     1.3    73.2    -      -       -      +
    295A  ALA*     1.3    56.4    +      -       -      +
    297A  GLN*     3.6    26.5    -      -       -      +
    298A  MET*     3.0    34.0    +      -       +      +
   1328G  LEU*     4.5    22.1    -      -       +      +
   1329G  MET*     6.2     5.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 295 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    293A  SER*     3.1     1.6    -      -       -      -
    294A  LEU*     1.3    79.0    -      -       -      +
    296A  ASP*     1.3    58.8    +      -       -      +
    298A  MET*     3.3    11.2    -      -       -      +
    299A  SER*     2.9    33.3    +      -       -      +
    383A  GLU*     4.2    24.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 296 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    292A  LEU*     4.4    18.7    -      -       +      +
    293A  SER*     3.0    20.1    +      -       -      +
    295A  ALA*     1.3    77.2    -      -       -      +
    297A  GLN*     1.3    66.6    +      -       -      +
    299A  SER*     3.0     5.7    +      -       -      -
    300A  LEU*     2.9    30.4    +      -       +      +
    381A  HIS      4.2     2.8    -      -       -      +
    382A  ILE*     3.7    17.8    -      -       +      +
    383A  GLU*     2.8    31.5    +      -       -      +
    384A  ASP*     2.9    34.3    +      -       -      +
    388A  VAL*     4.6     3.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 297 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    284A  LYS*     5.4     2.8    -      -       -      +
    289A  PHE*     3.3    55.6    +      -       +      +
    290A  SER*     3.4    16.8    +      -       -      +
    292A  LEU*     2.7    28.5    +      -       +      +
    293A  SER      3.0    12.4    +      -       -      +
    294A  LEU*     3.6    23.4    -      -       -      +
    296A  ASP*     1.3    75.0    -      -       -      +
    298A  MET*     1.3    64.4    +      -       -      +
    300A  LEU*     3.3     0.8    +      -       -      -
    301A  LEU*     3.2    28.7    +      -       -      +
   1328G  LEU*     3.4    25.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 298 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    294A  LEU*     3.0    19.1    +      -       +      +
    295A  ALA*     3.3    12.8    -      -       -      +
    297A  GLN*     1.3    78.2    -      -       -      +
    299A  SER*     1.3    52.7    +      -       -      +
    301A  LEU*     3.3     2.8    +      -       -      +
    302A  GLN*     2.8    56.9    +      -       -      +
   1321G  GLU*     5.0    10.1    -      -       +      +
   1324G  ILE*     3.8    19.9    -      -       +      +
   1325G  ARG*     4.0    42.2    -      -       -      +
   1328G  LEU*     3.7    21.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 299 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    295A  ALA*     2.9    20.1    +      -       -      +
    296A  ASP*     3.0     6.2    +      -       -      -
    298A  MET*     1.3    74.0    -      -       -      +
    300A  LEU*     1.3    66.1    +      -       -      +
    302A  GLN*     3.7    12.3    +      -       -      +
    303A  SER*     3.4    15.2    +      -       -      -
    379A  SER*     3.6    30.4    +      -       -      -
    381A  HIS*     4.1    17.2    +      -       -      +
    382A  ILE*     4.2    11.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 300 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    289A  PHE*     4.2    11.9    -      -       +      -
    292A  LEU*     4.1    24.9    -      -       +      -
    296A  ASP      2.9    18.2    +      -       -      +
    297A  GLN      3.9     3.6    -      -       -      +
    299A  SER*     1.3    74.4    -      -       -      +
    301A  LEU*     1.3    66.7    +      -       -      +
    303A  SER      3.2     1.6    +      -       -      -
    304A  ALA*     3.0    23.9    +      -       -      +
    374A  LEU*     3.7    22.0    -      -       +      +
    375A  ALA*     4.6     6.3    -      -       -      +
    377A  SER*     3.4    22.3    +      -       -      +
    378A  ASP      6.1     0.4    -      -       -      +
    379A  SER*     4.7     1.6    -      -       -      +
    382A  ILE*     3.3    34.5    -      -       +      -
    388A  VAL*     4.4    16.8    -      -       +      -
    391A  LEU*     4.2    15.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 301 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    279A  ILE*     4.2    20.2    -      -       +      -
    280A  ILE*     3.9    40.8    -      -       +      -
    283A  ALA*     4.3    11.9    -      -       +      -
    289A  PHE*     4.1    17.9    -      -       +      -
    297A  GLN      3.2    15.0    +      -       -      +
    298A  MET      3.6     6.5    -      -       -      +
    300A  LEU*     1.3    78.1    -      -       -      +
    302A  GLN*     1.3    63.2    +      -       -      +
    304A  ALA      4.6     0.2    -      -       -      +
    305A  TRP*     3.0    35.2    +      -       +      +
    308A  ILE*     5.0     3.1    -      -       +      -
    374A  LEU*     4.0    14.8    -      -       +      -
   1324G  ILE*     4.0    16.7    -      -       +      +
   1328G  LEU*     4.4    17.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 302 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    298A  MET*     2.8    43.5    +      -       -      +
    299A  SER*     3.7    12.6    +      -       -      +
    300A  LEU      3.2     0.4    -      -       -      -
    301A  LEU*     1.3    77.1    -      -       -      +
    303A  SER*     1.3    58.3    +      -       -      +
    305A  TRP*     3.1    21.2    +      -       -      -
    381A  HIS*     5.3    10.9    -      -       -      -
   1320G  LEU*     5.1     6.9    -      -       +      +
   1321G  GLU*     3.6    27.3    +      -       -      +
   1324G  ILE*     4.0    15.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 303 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    299A  SER      3.4     6.8    +      -       -      -
    300A  LEU      3.2     0.8    +      -       -      -
    301A  LEU      3.2     0.4    -      -       -      -
    302A  GLN*     1.3    81.0    -      -       -      +
    304A  ALA*     1.3    58.1    +      -       -      +
    305A  TRP*     3.7     3.8    +      -       -      -
    306A  MET*     5.1     0.9    +      -       -      +
    307A  GLU*     4.3     9.7    -      -       -      +
    377A  SER*     3.4    40.5    +      -       -      +
    378A  ASP      4.5     0.2    -      -       -      -
    379A  SER*     3.5    20.4    -      -       -      -
    428A  SER*     5.0     5.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 304 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    300A  LEU      3.0    14.6    +      -       -      +
    303A  SER*     1.3    74.8    -      -       -      +
    305A  TRP*     1.3    67.1    +      -       -      +
    306A  MET      3.2     3.4    -      -       -      -
    307A  GLU*     3.0    14.4    +      -       +      +
    308A  ILE*     2.9    30.1    +      -       +      +
    373A  ALA      3.8     6.3    -      -       -      +
    374A  LEU*     3.8    22.2    -      -       +      +
    377A  SER*     3.6    17.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 305 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    276A  LEU*     3.8    32.5    -      -       +      -
    279A  ILE*     4.5     4.0    -      -       +      +
    301A  LEU*     3.0    21.3    +      -       +      +
    302A  GLN*     3.1    30.0    +      -       -      -
    303A  SER      4.4     2.6    +      -       -      -
    304A  ALA*     1.3    79.1    -      -       -      +
    306A  MET*     1.3    96.6    +      -       +      +
    308A  ILE*     3.0    11.0    +      -       -      +
    309A  LEU*     2.8    37.6    +      -       +      +
    432A  VAL*     4.3    24.0    -      -       +      +
    435A  PHE*     6.0     5.2    -      +       -      -
    436A  TYR*     6.1     2.9    -      +       -      -
    500A  OHT      4.0    36.3    -      +       -      -
   1320G  LEU*     3.7    35.9    -      -       +      +
   1324G  ILE*     5.5     2.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 306 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    303A  SER      5.1     0.9    +      -       -      +
    304A  ALA      3.2     0.8    -      -       -      -
    305A  TRP*     1.3   106.0    -      -       +      +
    307A  GLU*     1.3    58.4    +      -       -      +
    309A  LEU*     4.4     7.2    -      -       -      -
    310A  ILE*     2.9    49.6    +      -       +      +
    428A  SER*     3.7    18.8    -      -       -      +
    431A  ALA*     3.8    20.6    -      -       +      -
    432A  VAL*     3.8    28.5    -      -       +      +
    435A  PHE*     5.3     2.7    -      -       +      -
    500A  OHT      3.6    47.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 307 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    303A  SER      4.3     9.9    +      -       -      +
    304A  ALA*     3.0    17.2    +      -       -      +
    306A  MET*     1.3    77.8    -      -       -      +
    308A  ILE*     1.3    56.6    +      -       -      +
    311A  LEU*     2.9    31.4    +      -       -      +
    373A  ALA*     3.9    26.0    -      -       +      +
    377A  SER*     5.6     1.8    -      -       -      -
    421A  LEU*     5.3     2.4    -      -       -      +
    424A  LEU*     3.6    31.9    -      -       +      +
    425A  ARG*     2.8    48.4    +      -       -      +
    428A  SER*     3.5    21.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 308 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    279A  ILE*     3.9    37.2    -      -       +      +
    282A  TRP*     4.2    13.5    -      -       +      -
    301A  LEU*     5.0     2.0    -      -       +      -
    304A  ALA*     2.9    35.9    +      -       +      +
    305A  TRP*     3.5     7.2    -      -       -      +
    307A  GLU*     1.3    74.1    -      -       -      +
    309A  LEU*     1.3    65.7    +      -       -      +
    311A  LEU*     3.4     5.6    +      -       -      +
    312A  GLY*     3.0    19.1    +      -       -      -
    370A  LYS*     3.7    41.9    -      -       +      +
    373A  ALA*     4.9     4.3    -      -       +      -
    374A  LEU*     4.2    22.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 309 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    272A  ALA*     4.0    24.0    -      -       +      +
    275A  GLU*     3.3    47.6    -      -       +      +
    276A  LEU*     4.2     6.5    -      -       +      +
    279A  ILE*     3.8    15.9    -      -       +      -
    305A  TRP*     2.8    40.5    +      -       +      +
    306A  MET*     3.9     6.3    -      -       -      +
    308A  ILE*     1.3    73.1    -      -       -      +
    310A  ILE*     1.3    58.4    +      -       -      +
    312A  GLY*     2.9    19.1    +      -       -      -
    313A  VAL*     3.2    11.8    +      -       -      +
    500A  OHT      3.8    35.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 310 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    306A  MET*     2.9    33.2    +      -       +      +
    307A  GLU      4.1     1.3    -      -       -      +
    309A  LEU*     1.3    76.6    -      -       -      +
    311A  LEU*     1.3    61.9    +      -       -      +
    313A  VAL*     3.1    15.8    -      -       -      +
    314A  VAL*     3.1    17.7    -      -       +      +
    345A  LEU*     5.9     0.2    -      -       +      -
    349A  ILE*     4.6    19.1    -      -       +      -
    352A  LEU*     4.0    17.7    -      -       +      -
    424A  LEU*     3.8    18.8    -      -       +      -
    427A  THR*     4.1    13.9    -      -       +      -
    428A  SER*     3.9    12.8    -      -       -      -
    431A  ALA*     3.7    30.5    -      -       +      -
    500A  OHT      4.8    10.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 311 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    307A  GLU      2.9    19.9    +      -       -      +
    308A  ILE*     4.0     3.8    -      -       -      +
    309A  LEU      3.2     0.2    -      -       -      -
    310A  ILE*     1.3    75.4    -      -       -      +
    312A  GLY*     1.3    62.9    +      -       -      +
    314A  VAL*     3.6     7.2    +      -       +      +
    315A  TYR*     3.2    13.3    +      -       -      +
    356A  TYR*     3.8    36.8    -      -       +      +
    361A  LEU*     5.4     3.4    -      -       +      -
    366A  PHE*     3.1    30.1    -      -       +      +
    369A  LEU*     4.2    11.4    -      -       +      +
    370A  LYS*     3.7    38.4    -      -       +      +
    373A  ALA*     5.0     1.6    -      -       +      -
    421A  LEU*     6.2     0.2    -      -       +      -
    424A  LEU*     4.0    27.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 312 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    275A  GLU*     5.6     0.4    -      -       -      -
    308A  ILE      3.0    10.1    +      -       -      -
    309A  LEU*     2.9    10.1    +      -       -      -
    311A  LEU*     1.3    74.2    -      -       -      +
    313A  VAL*     1.3    64.8    +      -       -      -
    315A  TYR*     3.2    11.4    +      -       -      +
    316A  ARG*     3.2    32.9    +      -       -      +
    366A  PHE*     3.9    17.4    -      -       -      -
    370A  LYS*     5.4     0.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 313 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    309A  LEU      3.2     5.4    +      -       -      +
    310A  ILE*     3.1    30.1    -      -       +      +
    312A  GLY*     1.3    73.6    -      -       -      +
    314A  VAL*     1.3    58.7    +      -       -      +
    315A  TYR      3.2     0.2    +      -       -      -
    316A  ARG*     3.3    24.8    +      -       -      +
    317A  SER*     2.6    40.6    +      -       -      +
    324A  LEU*     4.1    15.3    -      -       +      -
    325A  VAL      3.5    20.4    -      -       -      +
    326A  TYR*     4.1    30.3    -      -       +      +
    349A  ILE*     4.4    11.9    -      -       +      -
    500A  OHT      4.2     3.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 314 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    310A  ILE      3.1    19.8    +      -       -      +
    311A  LEU*     3.7    10.5    -      -       +      +
    312A  GLY      3.2     0.6    -      -       -      -
    313A  VAL*     1.3    77.1    -      -       -      +
    315A  TYR*     1.3    66.2    +      -       -      +
    317A  SER*     3.1    11.1    +      -       -      -
    318A  LEU*     3.4    11.2    +      -       +      +
    349A  ILE*     3.7    23.8    -      -       +      +
    352A  LEU*     3.8    24.7    -      -       +      +
    353A  VAL*     3.6    25.9    -      -       +      +
    356A  TYR*     3.8    33.0    -      -       +      -
    361A  LEU*     5.8     0.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 315 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    311A  LEU      3.2     4.2    +      -       -      +
    312A  GLY      3.2     2.8    +      -       -      +
    314A  VAL*     1.3    78.6    -      -       -      +
    316A  ARG*     1.3    64.3    +      -       +      +
    318A  LEU*     2.9    61.0    +      -       +      +
    361A  LEU*     4.3     9.8    +      -       +      -
    362A  GLU*     4.2     4.8    -      -       -      -
    363A  LYS*     3.4    61.8    +      -       +      +
    366A  PHE*     3.5    51.4    -      +       +      -
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Residues in contact with ARG 316 (chain A). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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    248A  LYS*     6.3     4.7    -      -       -      +
    275A  GLU*     3.6    16.8    +      -       -      -
    312A  GLY*     3.2    29.5    +      -       -      +
    313A  VAL*     3.4    26.3    -      -       -      +
    315A  TYR*     1.3    85.8    -      -       +      +
    317A  SER*     1.3    58.8    +      -       -      +
    318A  LEU      3.4     0.4    +      -       -      -
    319A  SER*     5.0     0.9    +      -       -      -
    320A  PHE*     3.9     9.5    -      -       -      -
    325A  VAL*     3.2    37.8    +      -       +      +
    326A  TYR*     2.8    30.0    +      -       -      +
    327A  ALA*     4.7     2.9    -      -       -      +
    366A  PHE*     6.3     0.7    -      -       +      -
    500A  OHT      3.3    20.0    +      -       -      -
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Residues in contact with SER 317 (chain A). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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    313A  VAL*     2.6    28.0    +      -       -      +
    314A  VAL      3.4     6.1    -      -       -      -
    315A  TYR      2.9     0.8    +      -       -      -
    316A  ARG*     1.3    77.2    -      -       -      +
    318A  LEU*     1.3    63.6    +      -       -      +
    319A  SER      3.4     2.0    -      -       -      -
    320A  PHE*     3.1    23.2    +      -       -      +
    323A  GLU      3.9    13.8    -      -       -      +
    324A  LEU*     3.6     4.0    -      -       -      +
    325A  VAL*     3.2    26.2    +      -       -      -
    353A  VAL*     3.7    22.2    -      -       -      +
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
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  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
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Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il