Contacts of the helix formed by residues 519 - 544 (chain B) in PDB entry 2XER


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 ARG 519 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    517B  ASP*     3.2     8.4    -      -       +      +
    518B  LYS*     1.3    82.4    -      -       +      +
    520B  ARG*     1.3    57.6    +      -       +      +
    521B  LYS      3.4     0.2    -      -       -      -
    522B  THR*     3.9     7.7    -      -       -      -
    523B  LEU*     3.1    49.3    +      -       +      +
    586B  GLN*     5.7     0.4    -      -       -      -
    589B  CYS*     4.7    10.1    +      -       -      +
    590B  ILE*     4.0    38.6    -      -       +      +
    591B  ARG      5.5     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 520 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    517B  ASP*     3.2    34.9    -      -       -      +
    518B  LYS      2.8     0.2    -      -       -      -
    519B  ARG*     1.3    80.6    -      -       +      +
    521B  LYS*     1.3    59.7    +      -       +      +
    523B  LEU*     3.7     8.3    +      -       +      +
    524B  VAL*     3.1    29.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 521 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    517B  ASP      5.0     2.7    -      -       -      +
    518B  LYS*     2.8    19.7    +      -       +      +
    520B  ARG*     1.3    75.9    -      -       +      +
    522B  THR*     1.3    62.3    +      -       -      +
    524B  VAL*     3.5     8.6    +      -       -      +
    525B  ILE*     3.2    28.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 522 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    518B  LYS      3.2     8.3    +      -       -      -
    519B  ARG*     4.0     9.1    -      -       -      -
    520B  ARG      3.3     0.2    -      -       -      -
    521B  LYS*     1.3    74.4    -      -       -      +
    523B  LEU*     1.3    56.7    +      -       -      +
    524B  VAL      3.0     4.7    -      -       -      -
    525B  ILE*     3.0     9.0    +      -       +      +
    526B  ILE*     2.9    27.5    +      -       +      +
    583B  HIS*     5.1     7.2    +      -       +      +
    586B  GLN*     2.8    29.6    +      -       +      +
    587B  ILE*     4.0    35.2    -      -       +      +
    590B  ILE*     3.7    22.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 523 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    519B  ARG*     3.1    45.7    +      -       +      +
    520B  ARG*     4.1     9.2    -      -       +      +
    521B  LYS      3.5     0.2    -      -       -      -
    522B  THR*     1.3    76.4    -      -       -      +
    524B  VAL*     1.3    58.5    +      -       +      +
    526B  ILE*     4.0    10.2    -      -       +      +
    527B  GLU*     3.1    32.9    +      -       -      +
    590B  ILE*     3.7    35.2    -      -       +      -
    592B  LYS*     6.1     2.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 524 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    520B  ARG      3.1    17.4    +      -       -      +
    521B  LYS*     3.6    11.7    -      -       -      +
    522B  THR      3.0     0.2    -      -       -      -
    523B  LEU*     1.3    78.7    -      -       +      +
    525B  ILE*     1.3    61.4    +      -       +      +
    526B  ILE      3.3     0.2    -      -       -      -
    527B  GLU*     3.4     5.2    +      -       +      +
    528B  LYS*     2.9    55.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 525 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    521B  LYS      3.2    17.0    +      -       -      +
    522B  THR*     3.0    10.4    +      -       -      +
    524B  VAL*     1.3    75.1    -      -       +      +
    526B  ILE*     1.3    63.9    +      -       -      +
    528B  LYS*     3.3    12.4    +      -       +      +
    529B  THR*     2.7    40.0    +      -       -      +
    568B  ASN*     4.3    23.3    +      -       +      +
    569B  LEU*     5.9     0.4    -      -       +      -
    583B  HIS*     3.7    29.6    -      -       +      +
    587B  ILE*     3.9    26.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 526 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    522B  THR*     2.9    18.8    +      -       +      +
    523B  LEU*     4.0    10.5    -      -       +      +
    525B  ILE*     1.3    77.6    -      -       -      +
    527B  GLU*     1.3    56.2    +      -       -      +
    529B  THR      3.2     1.2    +      -       -      -
    530B  TYR*     2.6    35.0    +      -       +      +
    587B  ILE*     4.0    22.2    -      -       +      -
    590B  ILE*     3.6    37.5    -      -       +      -
    592B  LYS*     4.3    27.1    -      -       +      -
    593B  GLY*     3.6    24.9    -      -       -      +
    596B  MET*     3.5    20.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 527 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    523B  LEU*     3.1    22.0    +      -       -      +
    524B  VAL*     3.4     6.8    +      -       -      +
    525B  ILE      3.3     0.4    -      -       -      -
    526B  ILE*     1.3    78.3    -      -       -      +
    528B  LYS*     1.3    65.8    +      -       -      +
    530B  TYR*     3.8     6.9    -      -       -      +
    531B  SER*     3.0    25.3    +      -       -      -
    592B  LYS*     2.9    40.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 528 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    524B  VAL*     2.9    41.6    +      -       +      +
    525B  ILE*     3.7    14.4    -      -       +      +
    527B  GLU*     1.3    77.0    -      -       -      +
    529B  THR*     1.3    61.2    -      -       -      +
    531B  SER*     3.6     7.6    -      -       -      -
    532B  LEU*     3.5    24.4    +      -       +      +
    568B  ASN*     4.5     9.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 529 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    525B  ILE*     2.7    24.8    +      -       -      +
    526B  ILE      3.7     2.9    -      -       -      -
    528B  LYS*     1.3    75.4    -      -       -      +
    530B  TYR*     1.3    59.6    +      -       -      +
    531B  SER      3.1     2.0    -      -       -      -
    532B  LEU*     3.0     8.6    +      -       -      +
    533B  LEU      2.9    23.6    +      -       -      -
    565B  MET*     3.5    47.5    -      -       +      +
    568B  ASN*     2.8    23.2    +      -       +      +
    569B  LEU*     4.8     2.1    -      -       +      +
    596B  MET*     4.0    20.4    -      -       +      -
    600B  ILE*     4.2     3.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 530 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    526B  ILE      2.6    22.8    +      -       -      +
    527B  GLU*     3.2    10.1    +      -       -      +
    529B  THR*     1.3    73.5    -      -       -      +
    531B  SER*     1.3    57.0    +      -       -      +
    533B  LEU*     3.8     7.9    -      -       +      +
    534B  LEU*     3.2    51.2    +      -       +      +
    592B  LYS*     3.9    36.6    -      -       +      -
    595B  ARG*     4.6    13.2    +      -       -      -
    596B  MET*     3.7    31.6    -      -       +      -
    599B  ARG*     3.5    37.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 531 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    527B  GLU      3.0    16.2    +      -       -      -
    528B  LYS*     3.6     8.5    -      -       -      -
    530B  TYR*     1.3    78.0    -      -       -      +
    532B  LEU*     1.3    61.7    +      -       -      +
    534B  LEU*     3.7     8.0    +      -       -      +
    535B  ASP*     3.3    29.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 532 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    528B  LYS*     3.5    15.7    +      -       +      +
    529B  THR*     3.0    13.2    +      -       -      +
    531B  SER*     1.3    77.0    -      -       -      +
    533B  LEU*     1.3    66.4    +      -       -      +
    535B  ASP*     3.0    12.6    +      -       -      +
    536B  VAL*     2.9    24.8    +      -       -      +
    560B  HIS*     6.4     0.9    -      -       +      -
    561B  LYS*     4.0    32.8    -      -       +      +
    564B  SER*     3.9    24.2    -      -       -      +
    565B  MET*     3.7    25.1    -      -       +      +
    568B  ASN*     4.3    10.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 533 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    529B  THR      2.9    10.2    +      -       -      +
    530B  TYR*     3.8    14.1    -      -       +      +
    532B  LEU*     1.3    76.3    -      -       -      +
    534B  LEU*     1.3    53.3    +      -       +      +
    536B  VAL*     3.0     3.1    +      -       +      -
    537B  GLU*     2.8    73.9    +      -       +      +
    565B  MET*     3.4    26.3    -      -       +      +
    596B  MET*     4.1    21.5    -      -       +      +
    599B  ARG*     3.5    51.8    -      -       +      +
    600B  ILE*     4.4     0.4    -      -       +      -
    603B  PHE*     3.9     9.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 534 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    530B  TYR*     3.2    47.6    +      -       +      +
    531B  SER*     4.0     8.5    -      -       -      +
    532B  LEU      3.3     0.2    -      -       -      -
    533B  LEU*     1.3    78.1    -      -       -      +
    535B  ASP*     1.3    58.2    +      -       -      +
    537B  GLU*     3.9    16.3    -      -       +      +
    538B  ASP*     3.0    29.3    +      -       -      +
    599B  ARG*     4.2     8.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 535 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    531B  SER*     3.3    17.7    +      -       -      +
    532B  LEU*     3.0    15.8    +      -       -      +
    534B  LEU*     1.3    78.3    -      -       -      +
    536B  VAL*     1.3    59.0    +      -       -      +
    538B  ASP*     2.9    26.3    +      -       -      +
    539B  TYR*     2.9    17.2    -      -       +      -
    561B  LYS*     3.3    36.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 536 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    532B  LEU      2.9    19.4    +      -       -      +
    533B  LEU*     3.6     8.3    -      -       -      +
    535B  ASP*     1.3    75.5    -      -       -      +
    537B  GLU*     1.3    60.4    +      -       -      +
    538B  ASP      3.5     0.3    +      -       -      -
    539B  TYR*     3.5    22.9    +      -       -      +
    540B  GLU*     4.1     7.4    -      -       -      +
    558B  ARG*     3.6    25.4    -      -       +      -
    561B  LYS*     3.8    27.6    -      -       +      -
    562B  ILE*     3.8    17.0    -      -       +      -
    565B  MET*     4.3     7.2    -      -       -      -
    603B  PHE*     3.6    34.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 537 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    533B  LEU*     2.8    49.2    +      -       +      +
    534B  LEU*     4.1    11.6    -      -       +      +
    536B  VAL*     1.3    70.0    -      -       -      +
    538B  ASP*     1.3    63.9    +      -       -      +
    539B  TYR      3.2     0.4    +      -       -      -
    540B  GLU*     3.7    18.2    +      -       -      +
    541B  ARG*     4.4     2.3    +      -       -      +
    599B  ARG*     3.0    48.6    +      -       -      +
    603B  PHE*     3.7    18.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 538 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    534B  LEU      3.0    18.9    +      -       -      +
    535B  ASP*     2.9    10.7    +      -       -      +
    537B  GLU*     1.3    77.9    -      -       -      +
    539B  TYR*     1.3    57.1    +      -       -      +
    540B  GLU      3.1     1.1    -      -       -      -
    541B  ARG*     2.9    50.4    +      -       -      +
    542B  ARG*     3.0    34.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 539 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    535B  ASP*     2.9    34.5    +      -       +      -
    536B  VAL*     3.5    20.6    -      -       -      +
    537B  GLU      3.2     0.4    -      -       -      -
    538B  ASP*     1.3    77.4    -      -       -      +
    540B  GLU*     1.3    52.7    +      -       -      +
    542B  ARG*     3.4    19.8    +      -       -      +
    543B  TYR*     2.6    66.3    +      -       +      -
    554B  LEU*     3.4    33.7    -      -       +      -
    555B  MET*     5.8     1.2    -      -       -      +
    556B  ASP*     3.6    14.8    +      -       -      -
    557B  ASP*     3.4    18.9    +      -       -      +
    558B  ARG*     3.8    15.3    -      -       -      +
    561B  LYS*     3.1    33.3    +      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 540 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    536B  VAL      4.1     8.0    -      -       -      +
    537B  GLU*     3.7    11.1    +      -       -      +
    538B  ASP      3.1     0.8    -      -       -      -
    539B  TYR*     1.3    77.8    -      -       -      +
    541B  ARG*     1.3    60.3    +      -       -      +
    543B  TYR*     3.9     9.8    -      -       +      +
    544B  LEU*     3.9    17.5    +      -       -      +
    558B  ARG*     4.1     9.4    +      -       -      +
    603B  PHE*     4.0    24.4    -      -       -      -
    638C  SER*     3.3    30.1    +      -       -      +
    642C  LEU*     6.0     2.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 541 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    537B  GLU      4.4     1.8    +      -       -      +
    538B  ASP*     2.9    32.7    +      -       -      +
    540B  GLU*     1.3    79.8    -      -       -      +
    542B  ARG*     1.3    68.6    +      -       +      +
    543B  TYR      3.2     2.0    +      -       -      -
    544B  LEU*     3.6     7.3    +      -       -      +
    545B  LEU*     3.5    17.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 542 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    538B  ASP*     3.0    40.9    +      -       -      +
    539B  TYR*     3.4    20.5    +      -       -      +
    541B  ARG*     1.3    84.5    -      -       +      +
    543B  TYR*     1.3    60.3    +      -       -      +
    545B  LEU*     3.1    32.4    -      -       +      +
    546B  SER*     4.3     2.6    +      -       -      -
    554B  LEU*     3.2    54.6    -      -       +      +
    555B  MET*     4.9     5.5    -      -       -      +
    737C  ILE*     5.4     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 543 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    539B  TYR*     2.6    47.3    +      +       +      +
    540B  GLU*     3.9    15.3    -      -       +      +
    541B  ARG      3.2     0.4    -      -       -      -
    542B  ARG*     1.3    71.3    -      -       -      +
    544B  LEU*     1.3    59.7    +      -       -      +
    545B  LEU      2.8     9.1    +      -       -      -
    546B  SER      3.3    10.2    +      -       -      -
    554B  LEU*     3.8    20.0    -      -       +      -
    556B  ASP*     3.1    30.6    +      -       -      +
    558B  ARG*     3.1    33.3    +      -       -      -
    637C  LEU*     5.8     7.4    -      -       +      -
    638C  SER*     4.6    10.5    -      -       -      -
    641C  SER*     5.5     2.0    -      -       -      -
    737C  ILE*     3.3    27.5    -      -       +      +
    738C  SER*     3.6    29.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 544 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    540B  GLU      3.9    10.4    +      -       -      +
    541B  ARG*     3.6     9.8    +      -       -      +
    542B  ARG      3.5     0.2    -      -       -      -
    543B  TYR*     1.3    79.2    -      -       -      +
    545B  LEU*     1.3    51.9    +      -       -      +
    546B  SER      3.3     0.9    +      -       -      -
    547B  LEU*     2.4    50.7    +      -       +      +
----------------------------------------------------------
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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