Contacts of the helix formed by residues 426 - 448 (chain A) in PDB entry 2PY5


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 TYR 426 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    210A  VAL      4.6     0.2    -      -       -      -
    211A  PHE*     3.5    33.7    -      +       +      -
    212A  PRO*     3.7    29.8    -      -       +      -
    214A  LEU*     4.5    11.0    -      -       +      -
    264A  PRO      3.5    19.3    -      -       -      -
    265A  TYR*     3.0    20.4    +      -       -      -
    266A  GLY      2.6    29.4    +      -       -      -
    353A  PHE*     3.7    14.9    -      -       -      -
    393A  PHE*     2.9    21.2    +      -       +      +
    424A  PRO*     5.5     0.7    -      -       -      -
    425A  VAL*     1.3    81.8    -      -       +      +
    427A  THR*     1.3    66.4    +      -       -      +
    428A  PRO*     3.6    26.7    -      -       +      -
    429A  MET*     3.0    30.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 427 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    214A  LEU*     5.9     0.4    -      -       -      +
    219A  ASP*     2.6    30.0    +      -       -      +
    222A  VAL*     3.8    16.8    -      -       +      -
    223A  ARG*     3.3    37.9    +      -       +      +
    226A  TYR*     5.0     1.6    -      -       +      -
    393A  PHE      3.3    11.3    +      -       -      -
    394A  ALA*     3.8    19.4    -      -       +      +
    395A  SER      4.3     2.3    +      -       -      -
    424A  PRO*     4.7     2.3    -      -       -      +
    425A  VAL      4.1     0.2    -      -       -      -
    426A  TYR*     1.3    72.2    -      -       -      +
    428A  PRO*     1.4    69.6    -      -       -      +
    430A  GLY*     3.0    11.8    +      -       -      -
    431A  VAL*     3.0    15.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with PRO 428 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    214A  LEU*     4.3    10.5    -      -       +      -
    222A  VAL*     3.5    21.1    -      -       +      -
    264A  PRO*     3.4    10.0    -      -       +      +
    285A  ILE*     5.3     0.4    -      -       +      -
    353A  PHE*     3.4    37.2    -      -       +      -
    426A  TYR*     3.2    35.2    -      -       +      -
    427A  THR*     1.4    92.1    -      -       -      +
    429A  MET*     1.3    60.8    +      -       -      +
    431A  VAL*     3.3     3.3    +      -       +      -
    432A  PHE*     3.1    30.9    +      -       +      -
----------------------------------------------------------
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Residues in contact with MET 429 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    211A  PHE*     3.7    18.2    -      -       +      -
    263A  LEU*     3.7    28.0    -      -       +      -
    264A  PRO*     3.4    27.1    -      -       -      +
    359A  LEU*     3.7    14.8    -      -       +      -
    360A  PHE*     3.7    30.5    -      -       +      -
    393A  PHE*     3.8    24.7    -      -       +      -
    426A  TYR*     3.0    20.6    +      -       +      +
    428A  PRO*     1.3    77.8    -      -       -      +
    430A  GLY*     1.3    58.7    +      -       -      +
    432A  PHE*     3.4     0.7    +      -       -      -
    433A  ILE*     2.9    47.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 430 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    226A  TYR*     3.5    19.9    -      -       -      -
    390A  TYR*     4.5     9.2    -      -       -      -
    393A  PHE*     3.9    12.6    -      -       -      +
    394A  ALA*     4.5     4.9    -      -       -      -
    426A  TYR      3.9     2.0    +      -       -      -
    427A  THR      3.0     8.0    +      -       -      -
    429A  MET*     1.3    76.7    -      -       -      +
    431A  VAL*     1.3    64.9    +      -       -      +
    433A  ILE*     3.3     4.8    +      -       -      -
    434A  THR*     3.1    26.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 431 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  VAL*     3.5    32.3    -      -       +      +
    225A  ALA*     3.6    24.5    -      -       +      +
    226A  TYR*     3.7    28.8    -      -       +      +
    285A  ILE*     4.1     5.4    -      -       +      -
    329A  SER*     4.1    14.4    -      -       -      -
    427A  THR*     3.0    17.7    +      -       +      +
    428A  PRO*     3.5     9.2    -      -       +      +
    430A  GLY*     1.3    76.2    -      -       -      +
    432A  PHE*     1.3    69.9    +      -       +      +
    434A  THR*     3.3     3.9    +      -       -      -
    435A  ALA*     3.1    25.5    +      -       -      +
    438A  ARG*     4.4     2.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 432 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    263A  LEU*     3.9     9.0    -      -       +      -
    264A  PRO*     3.7    31.6    -      -       +      -
    283A  LEU*     3.8    26.9    -      -       +      -
    284A  HIS      3.5    15.0    -      -       -      -
    285A  ILE*     4.2    20.0    -      -       +      -
    329A  SER*     3.8    17.9    -      -       -      -
    330A  ASN*     3.2    29.4    -      -       -      -
    331A  VAL*     4.4    14.6    -      -       +      -
    353A  PHE*     4.5     8.1    -      +       -      -
    428A  PRO      3.1    23.3    +      -       -      +
    429A  MET      4.2     0.2    -      -       -      +
    431A  VAL*     1.3    81.4    -      -       +      +
    433A  ILE*     1.3    67.1    +      -       -      +
    435A  ALA*     4.1     2.0    -      -       -      -
    436A  TRP*     2.9    34.5    +      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 433 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254A  TYR*     3.8    24.7    -      -       +      +
    257A  GLN*     4.0     6.7    -      -       +      +
    258A  MET*     3.6    37.9    -      -       +      +
    263A  LEU*     4.1    17.7    -      -       +      -
    360A  PHE*     4.4     1.1    -      -       +      -
    390A  TYR*     3.8    33.4    -      -       +      -
    393A  PHE*     5.0     0.4    -      -       +      -
    429A  MET*     2.9    45.4    +      -       +      +
    430A  GLY*     4.0     4.0    -      -       -      +
    432A  PHE*     1.3    76.4    -      -       -      +
    434A  THR*     1.3    62.2    +      -       -      +
    436A  TRP*     3.9     3.6    -      -       -      +
    437A  ALA*     3.1    21.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 434 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    226A  TYR*     4.0     9.6    -      -       +      +
    227A  ARG      2.8    29.8    +      -       -      +
    228A  GLY*     4.6     5.6    -      -       -      +
    254A  TYR*     4.0    17.4    +      -       +      +
    390A  TYR*     3.6    33.0    -      -       +      +
    430A  GLY      3.1    12.1    +      -       -      +
    431A  VAL      3.3     9.9    +      -       -      -
    433A  ILE*     1.3    73.5    -      -       -      +
    435A  ALA*     1.3    60.5    +      -       -      +
    437A  ALA*     3.2     2.3    +      -       -      +
    438A  ARG*     2.9    41.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 435 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    329A  SER*     3.4    26.5    -      -       -      +
    331A  VAL*     3.7    15.7    -      -       +      +
    332A  ASP*     3.4    11.6    -      -       -      +
    335A  LEU*     5.3     0.2    -      -       -      +
    431A  VAL      3.1    20.3    +      -       -      +
    432A  PHE*     3.8     7.4    -      -       -      +
    433A  ILE      3.3     0.2    -      -       -      -
    434A  THR*     1.3    76.3    +      -       -      +
    436A  TRP*     1.3    56.9    +      -       -      +
    438A  ARG*     3.3    15.3    +      -       -      +
    439A  TYR*     2.9    28.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 436 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    257A  GLN*     3.5    16.8    -      -       +      +
    261A  ARG*     3.5    57.7    +      -       +      +
    262A  LEU*     2.9    34.9    +      -       +      -
    263A  LEU*     3.7    11.4    -      -       +      -
    283A  LEU*     5.2     5.4    -      -       +      -
    330A  ASN*     5.6     0.7    -      -       -      -
    331A  VAL*     3.8    21.1    -      -       +      +
    432A  PHE*     2.9    30.8    +      -       +      +
    433A  ILE      3.9     3.1    -      -       -      +
    435A  ALA*     1.3    76.8    -      -       -      +
    437A  ALA*     1.3    58.1    +      -       -      +
    439A  TYR*     3.3    18.7    +      +       +      +
    440A  THR*     2.9    32.6    +      -       -      -
   8004A  EDO      6.2     0.2    -      -       -      -
   9007A  EDO      3.7    37.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 437 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    253A  LEU*     3.7    22.9    -      -       +      +
    254A  TYR*     3.4    32.5    -      -       +      +
    257A  GLN*     3.7    12.3    -      -       +      +
    433A  ILE      3.1     9.8    +      -       -      +
    434A  THR      3.2     8.9    +      -       -      +
    436A  TRP*     1.3    72.2    -      -       -      +
    438A  ARG*     1.3    66.0    +      -       +      +
    440A  THR*     3.2    12.3    +      -       -      -
    441A  THR*     3.2    17.0    +      -       -      -
    457A  THR      4.4     1.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 438 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    225A  ALA      4.6     2.6    +      -       -      -
    227A  ARG*     3.1    44.3    +      -       -      +
    228A  GLY      2.8    38.1    +      -       -      +
    229A  GLY*     4.5     2.2    -      -       -      -
    230A  PHE*     4.1    27.4    -      -       +      +
    315A  TYR*     5.3     4.3    -      -       -      -
    332A  ASP*     2.9    40.9    +      -       -      +
    335A  LEU*     5.3     0.9    -      -       +      -
    431A  VAL      4.4     1.8    +      -       -      -
    434A  THR*     2.9    26.4    +      -       -      +
    435A  ALA*     3.4    18.1    -      -       -      +
    437A  ALA*     1.3    75.6    -      -       +      +
    439A  TYR*     1.3    58.5    +      -       -      +
    441A  THR*     3.2     3.0    +      -       -      -
    442A  ILE*     2.8    50.0    +      -       +      +
    457A  THR      5.5     1.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 439 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    261A  ARG*     3.8    23.1    -      -       -      -
    331A  VAL*     3.7    24.5    -      -       +      -
    335A  LEU*     4.0    25.7    -      -       +      +
    435A  ALA      2.9    14.5    +      -       -      +
    436A  TRP*     3.4    22.7    -      +       -      +
    438A  ARG*     1.3    75.9    -      -       -      +
    440A  THR*     1.3    58.3    +      -       -      +
    442A  ILE*     4.7     0.4    -      -       -      -
    443A  THR*     2.7    67.2    +      -       +      +
   9007A  EDO      3.5    27.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 440 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    250A  VAL*     4.2    12.1    -      -       +      -
    253A  LEU*     4.3     3.4    -      -       +      -
    257A  GLN*     3.1    13.9    +      -       -      -
    261A  ARG*     3.0    18.6    +      -       -      +
    436A  TRP      2.9    15.3    +      -       -      -
    437A  ALA      3.2     9.2    +      -       -      -
    439A  TYR*     1.3    82.8    -      -       -      +
    441A  THR*     1.3    61.3    +      -       -      +
    443A  THR*     3.3    11.9    +      -       -      -
    444A  ALA*     3.4     8.1    +      -       -      +
    481A  GLY      5.0     0.9    -      -       -      +
    483A  TRP*     3.6    26.2    +      -       +      +
   9008A  EDO      3.7    21.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 441 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230A  PHE*     4.3    10.8    -      -       +      +
    253A  LEU*     4.3     3.8    -      -       -      +
    437A  ALA      3.2     6.4    +      -       -      -
    438A  ARG*     3.2     8.3    +      -       -      -
    440A  THR*     1.3    75.8    -      -       -      +
    442A  ILE*     1.3    65.8    +      -       -      +
    444A  ALA*     3.3     2.8    +      -       -      +
    445A  ALA*     2.9    23.0    +      -       -      +
    455A  CYS*     4.1    20.4    -      -       +      -
    457A  THR      2.8    30.2    +      -       -      +
    458A  ASP*     3.8     3.5    -      -       -      -
    459A  SER      4.3     5.8    -      -       -      +
    460A  ILE*     4.0    19.0    -      -       +      +
    483A  TRP*     3.8    16.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 442 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230A  PHE*     3.7    43.5    -      -       +      -
    299A  ILE*     4.4     6.9    -      -       +      +
    301A  THR*     3.9    23.1    -      -       +      +
    332A  ASP*     6.1     0.2    -      -       -      +
    335A  LEU*     4.1    23.1    -      -       +      -
    339A  HIS*     3.8    26.9    -      -       +      +
    438A  ARG*     2.8    38.7    +      -       +      +
    439A  TYR      4.3     1.3    -      -       -      +
    441A  THR*     1.3    72.0    -      -       -      +
    443A  THR*     1.3    57.8    +      -       -      +
    445A  ALA*     3.4     6.0    +      -       -      +
    446A  GLN*     2.8    28.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 443 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    335A  LEU*     4.2    11.9    -      -       +      -
    439A  TYR*     2.7    64.0    +      -       +      +
    440A  THR*     3.3     8.0    +      -       -      -
    442A  ILE*     1.3    76.2    -      -       -      +
    444A  ALA*     1.3    59.7    +      -       -      +
    446A  GLN*     3.5     3.1    +      -       -      -
    447A  ALA*     3.0    16.5    +      -       -      +
   9013A  EDO      2.7    41.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 444 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    440A  THR      3.4     3.7    +      -       -      +
    441A  THR      3.3     1.2    +      -       -      +
    442A  ILE      3.3     0.4    -      -       -      -
    443A  THR*     1.3    77.7    +      -       -      +
    445A  ALA*     1.3    67.5    +      -       -      +
    447A  ALA*     3.2     9.5    +      -       -      +
    448A  CYS*     3.2    24.8    +      -       -      -
    460A  ILE*     4.1    12.1    -      -       +      -
    471A  ILE*     4.7    11.2    -      -       +      -
    474A  ILE*     5.0     4.9    -      -       +      -
    483A  TRP*     3.5    41.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 445 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230A  PHE*     5.6     0.2    -      -       +      -
    299A  ILE*     3.4    21.8    -      -       +      +
    441A  THR      2.9    17.2    +      -       -      +
    442A  ILE*     3.7     3.1    -      -       -      +
    444A  ALA*     1.3    77.0    -      -       -      +
    446A  GLN*     1.3    61.8    +      -       -      +
    448A  CYS*     3.0    15.6    +      -       -      +
    449A  TYR*     3.1    12.0    +      -       -      -
    452A  ILE*     3.8    17.8    -      -       +      +
    455A  CYS*     3.5    25.1    -      -       -      -
    460A  ILE*     4.1     6.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 446 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    297A  GLY      2.9    26.1    +      -       -      -
    298A  TYR*     3.6    18.1    -      -       +      -
    299A  ILE*     2.9    34.4    +      -       +      +
    339A  HIS*     3.2    18.7    -      -       +      -
    442A  ILE      2.8    20.7    +      -       -      +
    443A  THR*     3.8     4.7    -      -       -      +
    445A  ALA*     1.3    74.1    -      -       -      +
    447A  ALA*     1.3    62.3    +      -       -      +
    449A  TYR*     3.1    28.0    +      -       -      +
   9013A  EDO      3.9    26.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 447 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    443A  THR      3.0    18.3    +      -       -      +
    444A  ALA*     3.4     9.4    -      -       -      +
    446A  GLN*     1.3    75.6    -      -       -      +
    448A  CYS*     1.3    61.9    +      -       -      +
    449A  TYR      3.4     2.1    +      -       -      -
    450A  ASP*     5.2     1.0    -      -       -      +
    470A  VAL*     3.8    38.5    -      -       +      +
    471A  ILE*     4.7     4.3    -      -       +      -
   9013A  EDO      3.6    10.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 448 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    444A  ALA      3.2    15.2    +      -       -      +
    445A  ALA*     3.0     8.5    +      -       -      +
    447A  ALA*     1.3    78.4    -      -       -      +
    449A  TYR*     1.3    63.3    +      -       -      +
    450A  ASP*     3.2    10.5    -      -       -      +
    451A  ARG*     2.9    15.3    +      -       +      -
    452A  ILE*     3.0     9.9    +      -       -      +
    460A  ILE*     4.7     2.0    -      -       -      -
    462A  LEU*     3.8    24.7    -      -       +      -
    468A  PRO*     3.8    31.4    -      -       +      -
    470A  VAL*     5.6     0.9    -      -       -      -
    471A  ILE*     3.8    24.5    -      -       -      -
----------------------------------------------------------
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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