Contacts of the helix formed by residues 54 - 81 (chain D) 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 D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49D  TYR*     3.7     4.5    -      -       -      -
     52D  PHE*     3.1    13.7    -      -       -      +
     53D  PRO*     1.3    83.4    -      -       -      +
     55D  LYS*     1.3    63.9    +      -       -      +
     56D  THR*     3.4    11.2    +      -       -      -
     57D  ARG*     3.1    32.6    +      -       -      +
     58D  MET*     3.5    13.9    -      -       -      +
     34Z    C      3.6    23.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 55 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19D  LEU*     6.1     1.1    -      -       +      -
     31D  ARG*     4.0     6.3    -      -       -      +
     32D  ILE*     2.4    36.7    +      -       +      +
     34D  THR*     4.0    17.9    -      -       +      -
     37D  LEU*     5.3     4.0    -      -       +      -
     54D  SER*     1.3    72.2    -      -       -      +
     56D  THR*     1.3    66.0    +      -       -      +
     57D  ARG      3.1     0.2    -      -       -      -
     58D  MET*     2.9    39.2    +      -       +      +
     59D  PHE*     3.2    31.5    +      -       +      -
    116D  PHE*     5.4     0.4    -      -       -      +
    117D  GLU*     3.3    29.7    +      -       -      +
     33Z    A      2.6    35.2    +      -       -      -
     34Z    C      2.9    18.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 56 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54D  SER*     3.2    10.8    +      -       -      -
     55D  LYS*     1.3    80.1    -      -       -      +
     57D  ARG*     1.3    59.3    +      -       -      +
     59D  PHE*     3.2     2.8    +      -       -      -
     60D  ASP*     3.0    31.4    +      -       -      +
    117D  GLU*     4.9     3.1    -      -       -      +
    118D  GLN*     3.6    28.2    +      -       +      +
    120D  ARG*     2.9    34.8    -      -       -      +
    121D  LEU*     3.7    19.3    -      -       +      +
     34Z    C      5.2     2.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 57 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12D  ARG*     5.4     3.1    +      -       -      +
     52D  PHE*     4.0     9.9    -      -       +      -
     53D  PRO*     3.3    33.2    -      -       +      -
     54D  SER*     3.1    26.1    +      -       -      +
     55D  LYS      3.1     0.6    -      -       -      -
     56D  THR*     1.3    75.3    -      -       -      +
     58D  MET*     1.3    67.2    +      -       -      +
     60D  ASP*     2.4    39.1    +      -       -      +
     61D  SER*     3.0    26.2    +      -       -      -
    120D  ARG*     2.7    27.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET 58 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15D  ILE*     4.0    13.7    -      -       -      -
     16D  LEU*     3.4    16.7    -      -       +      +
     19D  LEU*     3.8    17.5    -      -       +      -
     34D  THR*     4.8     7.2    -      -       +      -
     37D  LEU*     3.4    31.4    -      -       +      -
     48D  LEU*     5.3     9.2    -      -       +      +
     49D  TYR*     5.1     4.7    -      -       +      +
     52D  PHE*     3.6    30.7    -      -       +      -
     54D  SER      3.5     7.2    -      -       -      +
     55D  LYS*     2.9    49.3    +      -       +      +
     57D  ARG*     1.3    77.5    -      -       -      +
     59D  PHE*     1.3    59.0    +      -       +      +
     61D  SER*     3.3     4.9    +      -       -      -
     62D  LEU*     3.0    23.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 59 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19D  LEU*     4.1    25.4    -      -       +      -
     23D  LEU*     3.9    25.6    -      -       +      -
     32D  ILE*     5.5     5.4    -      -       +      -
     55D  LYS*     3.2    28.8    +      -       +      -
     56D  THR      3.2     3.3    +      -       -      +
     58D  MET*     1.3    76.5    -      -       -      +
     60D  ASP*     1.3    56.0    +      -       -      +
     62D  LEU*     3.1     6.5    +      -       +      +
     63D  ILE*     2.7    41.9    +      -       +      +
    108D  ILE*     3.9    21.1    -      -       +      -
    113D  ALA*     4.3    15.5    -      -       +      -
    114D  LEU*     4.0    14.1    -      -       +      -
    117D  GLU*     3.6    35.7    -      -       +      -
    121D  LEU*     3.8    21.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 60 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56D  THR*     3.0    17.8    +      -       -      +
     57D  ARG*     2.4    45.0    +      -       -      +
     59D  PHE*     1.3    76.0    -      -       -      +
     61D  SER*     1.3    52.3    +      -       -      +
     63D  ILE*     3.2     1.8    +      -       -      -
     64D  GLU*     2.8    33.2    +      -       -      +
    120D  ARG*     2.5    29.7    +      -       -      -
    121D  LEU*     3.6     9.6    -      -       -      +
    124D  ARG*     2.8    38.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 61 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12D  ARG*     3.6    24.1    +      -       -      -
     16D  LEU*     3.7    25.4    -      -       -      -
     52D  PHE*     3.7     5.0    -      -       -      -
     57D  ARG      3.0    15.2    +      -       -      -
     58D  MET      3.4     9.6    -      -       -      -
     60D  ASP*     1.3    76.9    -      -       -      +
     62D  LEU*     1.3    62.3    +      -       -      +
     64D  GLU*     3.2    10.4    +      -       -      +
     65D  PHE*     3.0    22.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 62 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16D  LEU*     3.9    38.4    -      -       +      +
     19D  LEU*     3.5    38.8    -      -       +      -
     20D  ALA*     4.5     5.4    -      -       +      +
     23D  LEU*     4.0     6.5    -      -       +      -
     58D  MET      3.0     7.8    +      -       -      +
     59D  PHE*     3.1     9.2    +      -       +      +
     61D  SER*     1.3    78.5    -      -       -      +
     63D  ILE*     1.3    59.6    +      -       -      +
     65D  PHE*     3.3    11.9    +      -       +      +
     66D  ILE*     3.1    28.5    +      -       -      +
    105D  LEU*     3.7    20.6    -      -       +      +
    108D  ILE*     3.9    24.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 63 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59D  PHE      2.7    23.9    +      -       -      +
     60D  ASP*     3.6     6.3    -      -       -      +
     62D  LEU*     1.3    69.6    -      -       -      +
     64D  GLU*     1.3    67.1    +      -       -      +
     66D  ILE*     3.2     8.9    +      -       +      +
     67D  GLU*     2.9    26.7    +      -       +      +
    108D  ILE*     3.8    25.1    -      -       +      -
    114D  LEU*     4.6     3.1    -      -       +      -
    121D  LEU*     3.7    47.3    -      -       +      +
    124D  ARG*     3.9    31.0    -      -       +      +
    125D  ILE*     3.9    22.2    -      -       +      -
    128D  LEU*     5.9     3.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 64 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60D  ASP*     2.8    16.0    +      -       -      +
     61D  SER*     3.2     8.8    +      -       -      +
     63D  ILE*     1.3    72.3    -      -       -      +
     65D  PHE*     1.3    64.2    +      -       -      +
     67D  GLU*     3.2     5.7    +      -       -      +
     68D  ASP*     2.8    39.2    +      -       -      +
    124D  ARG*     2.9    40.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 65 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61D  SER      3.0    12.6    +      -       -      +
     62D  LEU*     3.4    14.8    -      -       +      +
     63D  ILE      3.2     0.2    -      -       -      -
     64D  GLU*     1.3    76.8    -      -       -      +
     66D  ILE*     1.3    59.8    +      -       -      +
     68D  ASP*     3.2     7.3    +      -       +      +
     69D  SER*     2.7    49.7    +      -       -      -
     73D  ARG*     5.7     3.8    -      -       -      -
     98D  PHE*     4.1     9.9    -      +       -      -
    102D  ASN*     4.8     5.4    -      -       -      -
    105D  LEU*     3.6    31.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 66 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62D  LEU      3.1    18.5    +      -       -      +
     63D  ILE*     3.2    14.1    +      -       +      +
     65D  PHE*     1.3    76.0    -      -       -      +
     67D  GLU*     1.3    63.6    +      -       -      +
     69D  SER*     3.5     0.5    +      -       -      -
     70D  LEU*     3.0    32.3    +      -       +      +
     98D  PHE*     3.8    24.9    -      -       +      -
    105D  LEU*     4.0    47.1    -      -       +      +
    108D  ILE*     4.2    16.6    -      -       +      -
    109D  LEU*     4.3    14.4    -      -       +      -
    125D  ILE*     5.0     3.4    -      -       +      -
    128D  LEU*     3.9    20.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 67 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63D  ILE*     2.9    17.4    +      -       +      +
     64D  GLU*     3.5     5.3    -      -       -      +
     66D  ILE*     1.3    75.5    -      -       -      +
     68D  ASP*     1.3    69.5    +      -       -      +
     70D  LEU*     5.0     0.2    -      -       -      -
     71D  ILE*     2.8    36.2    +      -       +      +
    124D  ARG*     3.9    27.8    +      -       -      +
    128D  LEU*     3.7    39.4    -      -       +      +
    131D  ARG*     4.1    21.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 68 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64D  GLU*     2.8    35.1    +      -       -      +
     65D  PHE*     3.7     7.0    -      -       +      +
     67D  GLU*     1.3    75.2    -      -       -      +
     69D  SER*     1.3    63.0    +      -       -      +
     71D  ILE*     5.0     2.0    -      -       -      -
     72D  THR*     2.6    38.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 69 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65D  PHE*     2.7    46.6    +      -       -      -
     66D  ILE      3.7     1.8    -      -       -      -
     68D  ASP*     1.3    77.3    -      -       -      +
     70D  LEU*     1.3    58.2    +      -       -      +
     73D  ARG*     2.7    59.7    +      -       -      +
     98D  PHE*     3.5    25.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 70 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66D  ILE*     3.0    35.5    +      -       +      +
     67D  GLU*     4.1     2.5    -      -       -      +
     69D  SER*     1.3    81.3    -      -       -      +
     71D  ILE*     1.3    59.7    +      -       +      +
     73D  ARG*     3.4     1.7    +      -       -      -
     74D  ILE*     2.8    36.9    +      -       +      +
     94D  LEU*     3.8    24.0    -      -       +      +
     95D  ILE*     4.6    15.3    -      -       +      +
     98D  PHE*     3.7    37.9    -      -       +      -
    109D  LEU*     4.8     9.9    -      -       +      -
    128D  LEU*     4.2     6.7    -      -       +      -
    132D  ILE*     4.1    28.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 71 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67D  GLU*     2.8    32.9    +      -       +      +
     68D  ASP*     4.3     2.2    -      -       -      +
     70D  LEU*     1.3    75.8    -      -       -      +
     72D  THR*     1.3    64.1    +      -       -      +
     74D  ILE*     3.2    10.4    +      -       +      +
     75D  ASN*     3.0    39.0    +      -       -      +
    128D  LEU*     4.3    12.1    -      -       +      -
    131D  ARG*     3.7    58.8    -      -       +      +
    132D  ILE*     4.4    12.1    -      -       +      -
    135D  GLN*     5.7     6.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 72 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68D  ASP*     2.6    30.8    +      -       -      +
     69D  SER      3.8     2.7    -      -       -      -
     71D  ILE*     1.3    78.7    -      -       -      +
     73D  ARG*     1.3    71.9    +      -       -      +
     75D  ASN*     3.4     9.2    +      -       -      +
     76D  LEU*     3.1    39.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 73 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65D  PHE*     5.7     3.8    -      -       -      -
     69D  SER*     2.7    57.1    +      -       -      +
     72D  THR*     1.3    85.7    -      -       -      +
     74D  ILE*     1.3    65.8    +      -       -      +
     76D  LEU*     3.3    14.7    +      -       -      +
     77D  ILE*     3.0    26.2    +      -       +      +
     94D  LEU*     3.5    37.5    -      -       +      +
     98D  PHE*     5.3     6.4    -      -       +      -
    101D  ARG*     5.2    10.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 74 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70D  LEU*     2.8    30.6    +      -       +      +
     71D  ILE*     3.2    13.7    +      -       +      +
     73D  ARG*     1.3    77.1    -      -       -      +
     75D  ASN*     1.3    65.1    +      -       -      +
     77D  ILE*     3.0     9.9    +      -       +      +
     78D  LEU*     3.0    32.7    +      -       +      +
     91D  ILE*     3.4    53.2    -      -       +      +
     94D  LEU*     3.2    23.1    -      -       +      -
     95D  ILE*     5.3     3.4    -      -       +      -
    132D  ILE*     5.5     7.6    -      -       +      -
    135D  GLN*     4.2    19.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 75 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71D  ILE*     3.0    33.2    +      -       -      +
     72D  THR*     3.7     9.2    -      -       -      +
     73D  ARG      3.3     0.2    -      -       -      -
     74D  ILE*     1.3    75.8    -      -       -      +
     76D  LEU*     1.3    66.3    +      -       +      +
     78D  LEU*     3.2    11.4    +      -       -      +
     79D  LYS*     3.1    39.4    +      -       -      +
    135D  GLN*     4.1    18.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 76 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72D  THR*     3.1    29.5    +      -       +      +
     73D  ARG*     3.5    17.3    -      -       +      +
     74D  ILE      3.2     0.2    -      -       -      -
     75D  ASN*     1.3    76.8    -      -       +      +
     77D  ILE*     1.3    62.6    +      -       +      +
     79D  LYS*     3.0    13.7    +      -       +      +
     80D  ASP*     2.9    38.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 77 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73D  ARG*     3.0    20.7    +      -       +      +
     74D  ILE*     3.0    13.8    +      -       +      +
     76D  LEU*     1.3    75.1    -      -       +      +
     78D  LEU*     1.3    64.6    +      -       +      +
     80D  ASP*     3.1     4.5    +      -       +      -
     81D  GLU*     2.8    31.9    +      -       +      +
     87D  ARG*     4.2    21.8    -      -       -      +
     90D  LEU*     3.5    52.5    -      -       +      +
     91D  ILE*     4.3    11.4    -      -       +      -
     94D  LEU*     5.3     4.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 78 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74D  ILE*     3.0    19.4    +      -       +      +
     75D  ASN*     3.2    13.9    +      -       -      +
     77D  ILE*     1.3    77.6    -      -       -      +
     79D  LYS*     1.3    62.7    +      -       +      +
     81D  GLU      3.2     6.6    -      -       -      +
     87D  ARG*     2.9    50.0    +      -       +      +
     91D  ILE*     4.4     8.7    -      -       +      -
    135D  GLN*     3.5    35.2    -      -       -      +
    138D  GLN*     4.7     6.7    -      -       -      +
    139D  VAL*     3.5    27.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 79 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75D  ASN*     3.1    26.5    +      -       -      +
     76D  LEU*     3.0    17.2    +      -       +      +
     78D  LEU*     1.3    79.0    -      -       +      +
     80D  ASP*     1.3    66.7    +      -       -      +
     81D  GLU      5.2     0.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 80 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76D  LEU*     2.9    35.6    +      -       -      +
     77D  ILE*     4.1     3.8    -      -       +      +
     79D  LYS*     1.3    85.1    -      -       -      +
     81D  GLU*     1.3    60.3    +      -       +      +
     82D  LYS      4.3     0.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 81 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77D  ILE*     2.8    14.8    +      -       +      +
     78D  LEU      3.2     9.0    -      -       -      +
     79D  LYS      3.5     1.4    -      -       -      -
     80D  ASP*     1.3    83.0    -      -       +      +
     82D  LYS*     1.3    57.4    +      -       -      +
     83D  ASP*     2.8    29.6    +      -       -      +
     86D  ALA*     3.4    32.4    -      -       +      +
     87D  ARG*     2.6    44.5    +      -       +      +
     90D  LEU*     4.1    20.5    -      -       +      +
----------------------------------------------------------
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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