Contacts of the helix formed by residues 260 - 285 (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 260 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    258A  PRO      3.3     5.2    +      -       -      -
    259A  ASP*     1.3    77.0    -      -       -      +
    261A  ASP*     1.3    73.6    +      -       -      +
    262A  ILE      3.3     0.3    +      -       -      -
    263A  LYS*     3.4    12.3    +      -       -      +
    264A  ALA*     3.2    19.6    +      -       -      +
    339A  LEU*     4.0    20.3    -      -       -      +
    447A  HIS*     3.0    31.7    +      -       -      -
    298E  MET*     4.0    12.3    -      -       -      -
    302E  GLN*     5.9     1.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 261 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    260A  SER*     1.3    75.4    -      -       -      +
    262A  ILE*     1.3    93.2    +      -       -      +
    264A  ALA*     3.2     6.2    +      -       -      +
    265A  LEU*     3.0    29.6    +      -       +      +
    339A  LEU*     3.3    26.5    +      -       -      +
    340A  ALA*     3.9    15.6    -      -       -      +
    443A  LYS*     5.0     9.7    +      -       -      +
    302E  GLN*     3.8    25.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 262 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    260A  SER*     3.2     1.2    +      -       -      -
    261A  ASP*     1.3   100.2    +      -       -      +
    263A  LYS*     1.3    56.5    +      -       -      +
    265A  LEU*     3.1    12.4    +      -       +      -
    266A  THR*     2.6    51.8    +      -       -      +
    443A  LYS*     4.5     7.4    -      -       +      +
    444A  VAL*     3.9    49.6    -      -       +      +
    447A  HIS*     3.3    48.7    -      -       +      +
    448A  LYS*     4.6     3.6    -      -       +      -
    302E  GLN*     4.4     2.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 263 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    253A  PRO*     4.0    22.2    -      -       -      +
    254A  ASP*     2.5    35.6    +      -       -      +
    255A  PRO*     4.2     5.5    +      -       -      +
    257A  VAL*     3.1    40.9    +      -       +      +
    258A  PRO      3.9     5.6    -      -       -      +
    259A  ASP*     4.3    17.2    +      -       -      +
    260A  SER*     3.4    23.4    +      -       -      +
    262A  ILE*     1.3    78.7    -      -       -      +
    264A  ALA*     1.3    56.4    +      -       -      +
    266A  THR*     3.5     5.9    -      -       -      -
    267A  THR*     2.7    46.2    +      -       -      +
    330A  TYR*     5.2     4.5    -      -       +      +
    447A  HIS*     4.6     2.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 264 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    260A  SER      3.2     7.8    +      -       -      +
    261A  ASP      3.2     4.1    +      -       -      +
    263A  LYS*     1.3    79.0    -      -       -      +
    265A  LEU*     1.3    65.5    +      -       -      +
    267A  THR*     3.5     2.1    +      -       -      -
    268A  LEU*     3.2    28.3    +      -       +      +
    330A  TYR*     3.3    21.3    +      -       -      +
    332A  MET*     4.7     8.7    -      -       +      -
    336A  GLN      5.1     1.3    -      -       -      +
    340A  ALA*     3.4    32.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 265 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    261A  ASP*     3.0    26.6    +      -       +      +
    262A  ILE*     3.6    21.5    -      -       +      +
    264A  ALA*     1.3    73.6    -      -       +      +
    266A  THR*     1.3    68.9    +      -       -      +
    268A  LEU*     2.7    18.6    +      -       -      +
    269A  CYS*     2.9    23.3    +      -       -      -
    340A  ALA*     4.2    13.0    -      -       +      +
    342A  LEU*     4.2    17.3    -      -       +      -
    434A  HIS*     5.3     0.7    -      -       +      +
    438A  ILE*     3.8    28.5    -      -       +      -
    444A  VAL*     5.2     6.5    -      -       +      -
    500A  OHT      3.8    30.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 266 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    262A  ILE*     2.6    39.5    +      -       -      +
    263A  LYS*     3.5     6.7    -      -       -      +
    265A  LEU*     1.3    72.2    -      -       -      +
    267A  THR*     1.3    64.0    +      -       -      +
    269A  CYS*     3.4     9.4    +      -       -      +
    270A  ASP*     3.2    23.5    +      -       +      +
    444A  VAL*     5.0     2.8    -      -       -      +
    448A  LYS*     3.6    27.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 267 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    251A  ALA*     4.2    23.3    -      -       +      +
    253A  PRO*     4.4    21.4    -      -       +      +
    254A  ASP      5.1     0.7    +      -       -      -
    263A  LYS*     2.7    38.0    +      -       -      +
    264A  ALA      3.8     4.5    -      -       -      -
    265A  LEU      2.8     0.4    +      -       -      -
    266A  THR*     1.3    75.9    -      -       -      +
    268A  LEU*     1.3    61.0    +      -       -      +
    270A  ASP*     3.9     3.0    +      -       -      +
    271A  LEU*     3.3    21.3    +      -       -      +
    330A  TYR*     3.9    31.5    +      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 268 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    264A  ALA      3.2    16.0    +      -       -      +
    265A  LEU*     2.7    14.2    +      -       -      +
    267A  THR*     1.3    70.3    -      -       -      +
    269A  CYS*     1.3    54.8    +      -       -      +
    271A  LEU*     3.5     5.4    -      -       +      +
    272A  ALA*     2.7    36.9    +      -       -      +
    326A  TYR*     3.5    42.0    -      -       +      -
    330A  TYR*     4.1    12.8    -      -       +      -
    332A  MET*     4.2    15.3    -      -       -      -
    342A  LEU*     3.8    29.2    -      -       +      -
    500A  OHT      3.6    39.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 269 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    265A  LEU*     2.9    32.2    +      -       -      -
    266A  THR*     3.7     9.4    -      -       -      +
    268A  LEU*     1.3    77.0    -      -       -      +
    270A  ASP*     1.3    62.2    +      -       -      +
    272A  ALA*     3.3     1.0    +      -       -      +
    273A  ASP*     3.0    33.9    +      -       -      +
    435A  PHE*     4.4    13.7    -      -       +      -
    438A  ILE*     6.6     0.4    -      -       -      -
    500A  OHT      3.8    27.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 270 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    251A  ALA      6.0     0.2    -      -       -      +
    266A  THR*     3.2    12.9    +      -       +      +
    267A  THR*     4.5     3.1    -      -       -      +
    269A  CYS*     1.3    79.2    -      -       -      +
    271A  LEU*     1.3    63.7    +      -       -      +
    273A  ASP*     3.3    10.9    +      -       -      +
    274A  ARG*     3.2    44.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 271 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    249A  ILE*     3.9    29.8    -      -       +      +
    250A  TYR      4.2    12.8    -      -       -      +
    251A  ALA*     4.3    16.6    -      -       +      -
    267A  THR      3.3    17.4    +      -       -      +
    268A  LEU*     3.3     9.6    +      -       +      +
    269A  CYS      3.2     0.2    -      -       -      -
    270A  ASP*     1.3    74.7    -      -       -      +
    272A  ALA*     1.3    68.2    +      -       -      +
    273A  ASP      3.0     0.5    +      -       -      -
    274A  ARG*     3.1    12.1    +      -       -      +
    275A  GLU*     2.9    49.4    +      -       -      +
    326A  TYR*     3.5    37.5    -      -       +      +
    327A  ALA*     4.4     0.7    -      -       +      -
    500A  OHT      4.1     8.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 272 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    268A  LEU      2.7    21.8    +      -       -      +
    269A  CYS      3.5     4.5    -      -       -      +
    271A  LEU*     1.3    73.3    -      -       -      +
    273A  ASP*     1.3    59.0    +      -       -      +
    275A  GLU*     3.1     1.7    +      -       -      +
    276A  LEU*     2.8    34.1    +      -       -      +
    309A  LEU*     4.0    13.1    -      -       +      +
    500A  OHT      3.5    52.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 273 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    269A  CYS*     3.0    23.3    +      -       -      +
    270A  ASP*     3.7    11.5    -      -       -      +
    271A  LEU      3.1     0.4    -      -       -      -
    272A  ALA*     1.3    76.2    -      -       -      +
    274A  ARG*     1.3    61.8    +      -       -      +
    276A  LEU*     3.6     8.6    +      -       -      +
    277A  VAL*     3.4    24.1    +      -       -      +
    500A  OHT      2.6    44.0    +      -       -      +
   1323G  ILE*     4.4    13.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 274 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    249A  ILE*     3.5    25.8    -      -       +      +
    250A  TYR      2.9    21.2    +      -       -      +
    251A  ALA      3.3    23.8    +      -       -      -
    252A  MET*     4.9    11.1    -      -       -      +
    270A  ASP*     3.2    40.6    +      -       -      +
    271A  LEU*     3.1    14.6    +      -       -      +
    273A  ASP*     1.3    75.0    -      -       +      +
    275A  GLU*     1.3    66.4    +      -       -      +
    277A  VAL*     3.2    16.8    +      -       -      +
    278A  VAL*     3.3    16.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 275 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    249A  ILE*     3.6    23.0    -      -       +      +
    271A  LEU*     2.9    40.6    +      -       +      +
    272A  ALA      3.5     3.6    -      -       -      +
    274A  ARG*     1.3    73.6    -      -       -      +
    276A  LEU*     1.3    53.5    +      -       -      +
    278A  VAL*     3.1    10.8    -      -       +      +
    279A  ILE*     2.7    41.6    +      -       +      +
    309A  LEU*     3.3    26.0    -      -       +      +
    312A  GLY*     5.6     0.2    -      -       -      -
    316A  ARG*     3.6    21.2    +      -       -      -
    326A  TYR      4.3     0.5    -      -       -      +
    500A  OHT      2.8    30.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 276 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    272A  ALA      2.8    22.2    +      -       -      +
    273A  ASP*     3.7     6.5    -      -       -      +
    275A  GLU*     1.3    71.6    -      -       -      +
    277A  VAL*     1.3    58.6    +      -       -      +
    279A  ILE*     3.0    14.4    +      -       +      +
    280A  ILE*     2.8    42.4    +      -       +      +
    301A  LEU*     6.6     0.2    -      -       +      -
    305A  TRP*     3.8    37.9    -      -       +      -
    309A  LEU*     4.2     9.6    -      -       +      -
    500A  OHT      3.4    33.7    -      -       -      -
   1320G  LEU*     4.0    17.5    -      -       +      -
   1323G  ILE*     4.3    20.4    -      -       +      -
   1324G  ILE*     5.9     3.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 277 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    273A  ASP      3.4    12.2    +      -       -      +
    274A  ARG*     3.2    11.3    +      -       -      +
    275A  GLU      3.2     1.0    -      -       -      -
    276A  LEU*     1.3    78.3    -      -       -      +
    278A  VAL*     1.3    67.1    +      -       +      +
    280A  ILE*     3.6     9.5    +      -       -      +
    281A  GLY*     3.2    17.0    +      -       -      -
   1323G  ILE*     3.9    19.1    -      -       +      -
   1327G  ALA*     4.7    13.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 278 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    246A  PRO*     4.4    24.3    -      -       +      +
    249A  ILE*     3.3    32.8    -      -       +      -
    274A  ARG      3.3     6.9    +      -       -      +
    275A  GLU*     3.1    18.4    -      -       +      +
    277A  VAL*     1.3    79.5    -      -       +      +
    279A  ILE*     1.3    58.4    +      -       +      +
    280A  ILE      3.1     1.8    -      -       -      -
    281A  GLY*     3.2     2.9    +      -       -      +
    282A  TRP*     2.7    36.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 279 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    246A  PRO*     5.7     0.9    -      -       -      -
    275A  GLU*     2.7    26.7    +      -       +      +
    276A  LEU*     3.0    17.4    +      -       +      +
    278A  VAL*     1.3    74.3    -      -       +      +
    280A  ILE*     1.3    59.2    +      -       +      +
    282A  TRP*     3.2    15.0    -      -       +      +
    283A  ALA*     2.8    24.1    +      -       -      +
    301A  LEU*     4.2    13.7    -      -       +      -
    305A  TRP*     4.5     3.1    -      -       -      +
    308A  ILE*     3.9    46.7    -      -       +      +
    309A  LEU*     3.8    39.3    -      -       +      +
    370A  LYS*     6.1     1.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 280 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    276A  LEU*     2.8    28.3    +      -       +      +
    277A  VAL      3.7     4.0    -      -       -      +
    279A  ILE*     1.3    75.0    -      -       +      +
    281A  GLY*     1.3    67.6    +      -       -      +
    283A  ALA*     2.9    22.6    +      -       -      +
    284A  LYS*     3.4    10.0    +      -       -      +
    301A  LEU*     3.9    23.3    -      -       +      -
   1323G  ILE*     4.0     5.6    -      -       +      +
   1324G  ILE*     3.4    40.6    -      -       +      +
   1327G  ALA*     3.7    31.6    -      -       +      +
   1328G  LEU*     4.1    26.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 281 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    277A  VAL      3.2     9.6    +      -       -      -
    278A  VAL*     3.2     7.5    +      -       -      -
    280A  ILE*     1.3    79.9    -      -       -      +
    282A  TRP*     1.3    61.4    +      -       -      +
    284A  LYS*     3.5    20.5    +      -       -      +
    285A  HIS*     3.4    18.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 282 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    241A  LEU*     4.6    17.3    +      -       +      +
    244A  ALA*     3.7    29.7    -      -       +      +
    245A  GLU*     4.7     2.2    +      -       -      -
    246A  PRO*     4.0    22.4    -      -       +      +
    278A  VAL      2.7    16.4    +      -       -      +
    279A  ILE*     3.2    34.1    -      -       +      +
    281A  GLY*     1.3    70.5    -      -       -      +
    283A  ALA*     1.3    74.7    +      -       +      +
    285A  HIS*     2.8    27.8    +      -       -      +
    286A  ILE*     3.5    33.9    +      -       +      +
    308A  ILE*     4.2    20.9    -      -       +      -
    367A  VAL*     4.2     7.4    -      -       -      +
    370A  LYS*     3.8    39.7    -      -       +      +
    371A  ALA*     3.7    22.2    -      -       +      -
    374A  LEU*     4.1    10.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 283 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    279A  ILE      2.8    16.0    +      -       -      +
    280A  ILE*     2.9    15.0    +      -       -      +
    282A  TRP*     1.3    81.4    -      -       +      +
    284A  LYS*     1.3    57.3    +      -       -      +
    286A  ILE*     2.8    33.3    +      -       -      +
    289A  PHE*     3.5    36.3    -      -       +      +
    301A  LEU*     4.3     8.3    -      -       +      -
    374A  LEU*     4.2    11.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 284 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    280A  ILE*     3.4    12.3    +      -       -      +
    281A  GLY*     3.6    14.8    -      -       -      +
    282A  TRP      3.0     0.8    +      -       -      -
    283A  ALA*     1.3    76.5    -      -       -      +
    285A  HIS*     1.3    63.7    +      -       +      +
    286A  ILE      3.3     7.5    +      -       -      +
    289A  PHE*     4.1     6.7    -      -       +      -
    290A  SER*     3.3    29.8    +      -       -      +
    297A  GLN*     5.4     2.2    -      -       -      +
   1327G  ALA      4.3     9.2    -      -       -      -
   1328G  LEU*     3.3    46.2    +      -       +      -
   1329G  MET      5.2     0.6    +      -       -      -
   1330G  GLY      4.3     9.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 285 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    240A  HIS*     2.9    38.4    +      -       -      +
    241A  LEU*     5.4     1.3    -      -       +      -
    244A  ALA*     3.8    32.7    -      -       +      +
    281A  GLY      3.4    24.0    +      -       -      -
    282A  TRP*     2.8    15.2    +      -       +      +
    284A  LYS*     1.3    78.4    -      -       +      +
    286A  ILE*     1.3    62.0    +      -       -      +
    287A  PRO*     3.5     1.6    -      -       -      +
----------------------------------------------------------
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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
------------------------------------------------------------
  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) +   -    +    +   +   +    +    -
------------------------------------------------------------
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