Contacts of the helix formed by residues 54 - 81 (chain C) in PDB entry 4GCK


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 54 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49C  TYR*     4.0     5.4    -      -       -      -
     52C  PHE*     3.3    12.5    -      -       -      +
     53C  PRO*     1.3    82.9    -      -       -      +
     55C  LYS*     1.3    65.1    +      -       -      +
     56C  THR*     3.6    13.0    -      -       -      -
     57C  ARG*     3.1    37.9    +      -       -      +
     58C  MET*     3.7     2.5    +      -       -      -
      9W    C      3.2    25.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 55 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19C  LEU*     6.0     1.1    -      -       +      -
     31C  ARG*     3.8     7.3    -      -       -      +
     32C  ILE*     3.1    26.3    +      -       +      +
     34C  THR*     4.6    15.3    -      -       +      +
     37C  LEU*     4.8     4.9    -      -       +      -
     49C  TYR*     4.7     0.6    +      -       -      -
     54C  SER*     1.3    70.3    -      -       -      +
     56C  THR*     1.3    67.2    +      -       -      +
     58C  MET*     2.8    43.9    +      -       +      +
     59C  PHE*     3.3    35.4    +      -       +      -
    117C  GLU*     2.6    29.2    +      -       -      +
      8W    A      2.9    41.3    +      -       -      -
      9W    C      3.0    18.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 56 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54C  SER*     3.6    12.5    -      -       -      -
     55C  LYS*     1.3    79.0    -      -       -      +
     57C  ARG*     1.3    61.4    +      -       -      +
     59C  PHE*     3.3    10.8    +      -       -      +
     60C  ASP*     2.9    25.1    +      -       -      +
    117C  GLU*     4.7     8.1    +      -       -      -
    118C  GLN*     3.7    30.4    +      -       +      +
    120C  ARG*     3.0    31.0    -      -       -      +
    121C  LEU*     4.2    10.2    -      -       +      +
      9W    C      5.2     2.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 57 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12C  ARG*     5.8     3.4    -      -       -      +
     52C  PHE*     4.1     8.7    -      -       +      -
     53C  PRO*     3.5    34.5    -      -       +      +
     54C  SER*     3.1    17.3    +      -       -      +
     55C  LYS      3.0     1.0    -      -       -      -
     56C  THR*     1.3    83.5    -      -       -      +
     58C  MET*     1.3    60.7    +      -       -      +
     60C  ASP*     2.8    39.7    +      -       -      +
     61C  SER*     2.8    31.9    +      -       -      +
    120C  ARG*     3.3    14.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET 58 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15C  ILE*     4.1     7.4    -      -       +      -
     16C  LEU*     3.7    15.1    -      -       +      +
     19C  LEU*     3.8    19.1    -      -       +      -
     34C  THR*     5.6     3.4    -      -       +      -
     37C  LEU*     3.4    28.9    -      -       +      -
     48C  LEU*     4.2    29.4    -      -       +      +
     49C  TYR*     5.7     3.8    -      -       +      -
     52C  PHE*     3.7    44.4    -      -       +      -
     54C  SER      4.0     2.2    -      -       -      +
     55C  LYS*     2.8    34.3    +      -       +      +
     57C  ARG*     1.3    77.0    -      -       -      +
     59C  PHE*     1.3    56.1    +      -       -      +
     61C  SER*     3.0     4.9    +      -       -      -
     62C  LEU*     2.9    27.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 59 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19C  LEU*     4.1    24.5    -      -       +      -
     23C  LEU*     4.3    15.0    -      -       +      -
     32C  ILE*     4.8     7.6    -      -       +      -
     55C  LYS*     3.3    29.6    +      -       +      -
     56C  THR*     3.7     6.5    -      -       -      +
     58C  MET*     1.3    77.3    -      -       -      +
     60C  ASP*     1.3    58.0    +      -       -      +
     62C  LEU*     3.1     6.6    +      -       -      +
     63C  ILE*     2.9    36.4    +      -       +      +
    108C  ILE*     4.1    26.0    -      -       +      -
    113C  ALA*     4.5    13.7    -      -       +      -
    114C  LEU*     3.9    17.7    -      -       +      -
    117C  GLU*     3.7    42.4    -      -       +      -
    121C  LEU*     3.8    15.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 60 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56C  THR      2.9    12.8    +      -       -      +
     57C  ARG*     2.8    32.4    +      -       -      +
     58C  MET      3.2     0.2    -      -       -      -
     59C  PHE*     1.3    76.9    -      -       -      +
     61C  SER*     1.3    62.2    +      -       -      +
     63C  ILE*     3.3     3.1    +      -       -      -
     64C  GLU*     3.0    37.3    +      -       -      +
    120C  ARG*     2.4    47.6    +      -       -      -
    121C  LEU*     3.4    10.6    -      -       -      +
    124C  ARG*     3.5    19.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 61 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12C  ARG*     3.1    30.0    +      -       -      -
     16C  LEU*     3.7    26.1    -      -       -      +
     52C  PHE*     3.8     1.7    -      -       -      -
     57C  ARG*     2.8    19.2    +      -       -      -
     58C  MET      3.0     8.0    +      -       -      -
     60C  ASP*     1.3    72.5    -      -       -      +
     62C  LEU*     1.3    65.0    +      -       -      +
     64C  GLU*     3.2    13.3    +      -       -      +
     65C  PHE*     3.1    22.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 62 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16C  LEU*     3.7    39.0    -      -       +      +
     19C  LEU*     3.2    39.5    -      -       +      -
     20C  ALA*     4.4     4.3    -      -       +      +
     23C  LEU*     4.4     5.2    -      -       +      -
     58C  MET      2.9     6.7    +      -       -      +
     59C  PHE*     3.1     8.3    +      -       -      +
     61C  SER*     1.3    79.7    -      -       -      +
     63C  ILE*     1.3    61.1    +      -       -      +
     65C  PHE*     3.3    10.4    +      -       +      +
     66C  ILE*     3.0    26.9    +      -       -      +
    105C  LEU*     3.6    23.0    -      -       +      +
    108C  ILE*     3.9    25.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 63 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59C  PHE*     2.9    20.5    +      -       -      +
     60C  ASP*     3.8     4.7    -      -       -      +
     62C  LEU*     1.3    73.3    -      -       +      +
     64C  GLU*     1.3    60.0    +      -       -      +
     66C  ILE*     3.2     7.4    +      -       +      +
     67C  GLU*     2.8    37.9    +      -       +      +
    108C  ILE*     4.0    22.4    -      -       +      -
    114C  LEU*     4.6     3.8    -      -       +      -
    121C  LEU*     3.8    46.4    -      -       +      +
    124C  ARG*     4.0    30.3    -      -       +      +
    125C  ILE*     3.7    24.0    -      -       +      -
    128C  LEU*     5.5     0.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 64 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60C  ASP*     3.0    24.5    +      -       -      +
     61C  SER*     3.2    13.6    +      -       -      +
     63C  ILE*     1.3    76.0    -      -       -      +
     65C  PHE*     1.3    58.6    +      -       -      +
     67C  GLU*     3.4     5.3    -      -       -      +
     68C  ASP*     2.9    42.1    +      -       -      +
    124C  ARG*     2.9    31.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 65 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61C  SER      3.1    12.0    +      -       -      +
     62C  LEU*     3.4    14.4    -      -       +      +
     63C  ILE      3.2     0.2    -      -       -      -
     64C  GLU*     1.3    74.9    -      -       -      +
     66C  ILE*     1.3    64.7    +      -       -      +
     68C  ASP*     3.9     6.0    -      -       +      +
     69C  SER*     2.6    52.9    +      -       -      -
     98C  PHE*     4.0    11.0    -      +       -      -
    102C  ASN*     4.5     6.3    -      -       -      -
    105C  LEU*     3.7    31.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 66 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62C  LEU      3.0    21.9    +      -       -      +
     63C  ILE*     3.6    11.0    -      -       +      +
     65C  PHE*     1.3    74.5    -      -       -      +
     67C  GLU*     1.3    65.4    +      -       -      +
     69C  SER*     3.8     1.6    -      -       -      -
     70C  LEU*     3.0    44.6    +      -       +      +
     98C  PHE*     3.9    19.1    -      -       +      -
    105C  LEU*     3.8    47.3    -      -       +      +
    108C  ILE*     4.0    21.8    -      -       +      -
    109C  LEU*     4.1    12.8    -      -       +      +
    125C  ILE*     4.9     3.8    -      -       +      -
    128C  LEU*     3.8    13.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 67 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63C  ILE*     2.8    25.9    +      -       +      +
     64C  GLU*     3.4     8.5    -      -       -      +
     66C  ILE*     1.3    78.4    -      -       -      +
     68C  ASP*     1.3    61.8    -      -       -      +
     70C  LEU*     3.7     0.7    -      -       -      +
     71C  ILE*     2.8    37.5    +      -       -      +
    124C  ARG*     4.9     7.0    -      -       -      +
    127C  GLN*     5.0     3.1    -      -       -      +
    128C  LEU*     3.5    46.6    +      -       +      +
    131C  ARG*     3.5    29.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 68 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64C  GLU*     2.9    29.9    +      -       -      +
     65C  PHE*     3.9     6.0    -      -       +      +
     67C  GLU*     1.3    75.0    -      -       -      +
     69C  SER*     1.3    69.7    +      -       -      +
     71C  ILE*     4.9     2.7    -      -       -      -
     72C  THR*     2.9    35.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 69 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65C  PHE*     2.6    46.8    +      -       -      -
     66C  ILE      3.8     1.1    -      -       -      -
     68C  ASP*     1.3    76.6    -      -       -      +
     70C  LEU*     1.3    64.6    +      -       -      +
     72C  THR*     4.0     1.9    -      -       -      -
     73C  ARG*     3.1    41.3    +      -       -      +
     98C  PHE*     3.6    26.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 70 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66C  ILE*     3.0    37.3    +      -       +      +
     67C  GLU*     3.8     3.1    -      -       -      +
     69C  SER*     1.3    80.2    -      -       -      +
     71C  ILE*     1.3    62.9    +      -       +      +
     73C  ARG      3.8     0.3    -      -       -      -
     74C  ILE*     2.9    37.5    +      -       +      +
     94C  LEU*     3.8    19.2    -      -       +      +
     95C  ILE*     4.8    15.3    -      -       +      +
     98C  PHE*     3.7    39.9    -      -       +      -
    109C  LEU*     4.7    10.5    -      -       +      -
    128C  LEU*     4.2     7.2    -      -       +      -
    132C  ILE*     4.2    25.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 71 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67C  GLU*     2.8    31.6    +      -       -      +
     68C  ASP*     4.3     2.2    -      -       -      +
     70C  LEU*     1.3    75.0    -      -       +      +
     72C  THR*     1.3    63.6    +      -       -      +
     74C  ILE*     3.3    11.1    +      -       +      +
     75C  ASN*     3.0    45.3    +      -       -      +
    128C  LEU*     4.2    12.6    -      -       +      -
    131C  ARG*     3.7    62.4    -      -       +      +
    132C  ILE*     4.6    11.0    -      -       +      +
    135C  GLN*     6.1     3.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 72 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68C  ASP*     2.9    28.3    +      -       -      +
     69C  SER*     4.0     3.1    -      -       -      -
     71C  ILE*     1.3    78.0    -      -       -      +
     73C  ARG*     1.3    64.6    +      -       +      +
     75C  ASN*     3.5     9.7    +      -       -      +
     76C  LEU*     3.2    35.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 73 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     69C  SER*     3.1    26.6    +      -       -      +
     72C  THR*     1.3    80.8    -      -       +      +
     74C  ILE*     1.3    65.4    +      -       -      +
     76C  LEU*     3.6    13.6    -      -       +      +
     77C  ILE*     3.0    27.0    +      -       +      +
     94C  LEU*     3.5    30.6    -      -       +      +
     98C  PHE*     4.8     6.2    -      -       -      -
    101C  ARG*     2.6    49.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 74 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70C  LEU*     2.9    29.2    +      -       +      +
     71C  ILE*     3.7    11.2    -      -       +      +
     73C  ARG*     1.3    75.2    -      -       -      +
     75C  ASN*     1.3    65.6    +      -       -      +
     77C  ILE*     3.0    10.5    +      -       -      +
     78C  LEU*     2.9    33.8    +      -       +      +
     91C  ILE*     3.9    42.0    -      -       +      -
     94C  LEU*     3.7    14.6    -      -       +      -
     95C  ILE*     5.3     2.0    -      -       +      -
    132C  ILE*     4.3    29.4    -      -       +      -
    135C  GLN*     4.3    18.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 75 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71C  ILE*     3.0    35.9    +      -       -      +
     72C  THR*     3.7     8.8    -      -       -      +
     74C  ILE*     1.3    76.8    -      -       -      +
     76C  LEU*     1.3    62.6    +      -       +      +
     78C  LEU*     3.1    17.7    +      -       -      +
     79C  LYS*     3.1    26.5    +      -       -      +
    135C  GLN*     3.7    20.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 76 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72C  THR*     3.2    28.8    +      -       +      +
     73C  ARG*     3.6    17.9    -      -       +      +
     74C  ILE      3.2     0.2    -      -       -      -
     75C  ASN*     1.3    75.7    -      -       +      +
     77C  ILE*     1.3    68.2    +      -       +      +
     79C  LYS*     3.1    12.6    +      -       +      +
     80C  ASP*     3.0    25.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 77 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73C  ARG*     3.0    20.7    +      -       +      +
     74C  ILE*     3.0     8.0    +      -       -      +
     76C  LEU*     1.3    78.3    -      -       +      +
     78C  LEU*     1.3    59.3    +      -       +      +
     79C  LYS      3.1     0.2    +      -       -      -
     80C  ASP*     4.7     3.6    -      -       -      -
     81C  GLU*     2.9    30.1    +      -       +      +
     87C  ARG*     4.2    22.7    -      -       +      +
     90C  LEU*     3.8    56.1    -      -       +      +
     91C  ILE*     4.0    15.5    -      -       +      +
     94C  LEU*     4.2    16.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 78 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74C  ILE*     2.9    24.1    +      -       +      +
     75C  ASN*     3.1    12.3    +      -       -      +
     77C  ILE*     1.3    76.8    -      -       +      +
     79C  LYS*     1.3    59.8    +      -       +      +
     81C  GLU      3.6     2.3    -      -       -      +
     87C  ARG*     2.8    50.7    +      -       +      +
     91C  ILE*     4.5     7.4    -      -       +      -
    135C  GLN*     3.2    39.0    -      -       -      +
    138C  GLN*     5.3     3.6    -      -       -      +
    139C  VAL*     3.5    27.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 79 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75C  ASN*     3.1    18.4    +      -       -      +
     76C  LEU*     3.1    15.0    +      -       +      +
     78C  LEU*     1.3    79.7    -      -       +      +
     80C  ASP*     1.3    59.5    +      -       -      +
     81C  GLU      3.6     1.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 80 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76C  LEU      3.0    15.6    +      -       -      +
     77C  ILE*     4.1     4.3    -      -       -      +
     79C  LYS*     1.3    77.2    -      -       -      +
     81C  GLU*     1.3    64.5    +      -       +      +
     82C  LYS      4.1     1.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 81 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77C  ILE      2.9    14.1    +      -       -      +
     78C  LEU      3.6     1.9    -      -       -      +
     79C  LYS      5.2     0.7    -      -       -      -
     80C  ASP*     1.3    84.1    -      -       +      +
     82C  LYS*     1.3    56.9    +      -       -      +
     83C  ASP*     2.9    39.0    +      -       -      +
     86C  ALA*     3.4    28.8    -      -       +      +
     87C  ARG*     2.8    48.3    +      -       +      +
     90C  LEU*     4.2    20.4    -      -       +      +
----------------------------------------------------------
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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