Contacts of the helix formed by residues 54 - 81 (chain A) 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 A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  TYR*     4.0     4.9    -      -       -      -
     52A  PHE*     3.2     6.3    -      -       -      +
     53A  PRO*     1.3    82.6    -      -       -      +
     55A  LYS*     1.3    64.1    +      -       -      +
     56A  THR*     3.4    11.8    +      -       -      -
     57A  ARG*     3.0    38.5    +      -       -      +
     58A  MET*     3.5    10.9    +      -       -      +
     30Z    C      3.4    24.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 55 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  LEU*     5.9     0.9    -      -       +      -
     31A  ARG*     4.1     3.6    -      -       -      +
     32A  ILE*     2.8    31.4    +      -       +      +
     33A  THR      5.4     0.2    -      -       -      -
     34A  THR*     4.4    17.9    -      -       +      -
     37A  LEU*     5.1     5.2    -      -       +      -
     49A  TYR*     4.6     1.2    +      -       -      -
     54A  SER*     1.3    70.2    -      -       -      +
     56A  THR*     1.3    68.2    +      -       -      +
     58A  MET*     2.9    35.7    +      -       -      +
     59A  PHE*     3.2    29.6    +      -       +      -
    117A  GLU*     2.7    35.6    +      -       -      +
     29Z    A      2.6    41.9    +      -       -      -
     30Z    C      2.9    18.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 56 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54A  SER*     3.4    12.2    +      -       -      -
     55A  LYS*     1.3    78.6    -      -       -      +
     57A  ARG*     1.3    58.9    +      -       -      +
     59A  PHE*     3.2     6.6    +      -       -      +
     60A  ASP*     3.0    24.9    +      -       -      +
    117A  GLU*     4.4     9.4    +      -       -      -
    118A  GLN*     3.6    24.3    +      -       +      +
    120A  ARG*     3.1    40.6    -      -       -      +
    121A  LEU*     4.0    14.7    -      -       +      +
     30Z    C      4.8     3.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 57 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  PHE*     4.2     7.4    -      -       +      -
     53A  PRO*     3.4    36.3    -      -       +      +
     54A  SER*     3.0    20.9    +      -       -      +
     55A  LYS      3.0     0.2    -      -       -      -
     56A  THR*     1.3    75.6    -      -       -      +
     58A  MET*     1.3    60.6    +      -       -      +
     60A  ASP*     3.1    34.3    +      -       -      +
     61A  SER*     2.9    33.6    +      -       -      -
    120A  ARG*     3.8     9.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET 58 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15A  ILE*     3.8    16.6    -      -       +      -
     16A  LEU*     3.7    16.3    -      -       +      +
     19A  LEU*     3.9    18.2    -      -       +      -
     34A  THR*     6.2     1.3    -      -       +      -
     37A  LEU*     3.6    22.2    -      -       +      -
     48A  LEU*     3.8    27.4    -      -       +      -
     49A  TYR*     6.2     4.0    -      -       +      -
     52A  PHE*     3.4    42.6    -      -       +      -
     54A  SER      3.6    11.0    -      -       -      +
     55A  LYS*     2.9    23.0    +      -       +      +
     57A  ARG*     1.3    77.4    -      -       -      +
     59A  PHE*     1.3    56.6    +      -       +      +
     61A  SER*     3.2     5.0    +      -       -      -
     62A  LEU*     2.9    26.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 59 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  LEU*     4.2    25.4    -      -       +      -
     23A  LEU*     4.2    12.8    -      -       +      -
     32A  ILE*     4.8    10.3    -      -       +      -
     55A  LYS*     3.2    29.5    +      -       +      -
     56A  THR      3.2     7.9    +      -       -      +
     58A  MET*     1.3    74.5    -      -       -      +
     60A  ASP*     1.3    55.1    +      -       -      +
     62A  LEU*     3.1     7.7    +      -       +      +
     63A  ILE*     2.7    40.9    +      -       +      +
    108A  ILE*     3.9    29.4    -      -       +      -
    113A  ALA*     4.4    16.6    -      -       +      -
    114A  LEU*     3.9    14.6    -      -       +      -
    117A  GLU*     3.8    32.8    -      -       +      -
    121A  LEU*     3.8    19.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 60 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56A  THR      3.0    14.3    +      -       -      +
     57A  ARG*     3.1    32.0    +      -       -      +
     59A  PHE*     1.3    75.9    -      -       -      +
     61A  SER*     1.3    52.0    +      -       -      +
     63A  ILE*     3.1     3.6    +      -       -      -
     64A  GLU*     2.7    33.2    +      -       -      +
    120A  ARG*     2.4    37.9    +      -       -      -
    121A  LEU*     3.5    11.8    -      -       -      +
    124A  ARG*     3.1    38.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 61 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  ARG*     2.7    33.0    +      -       -      -
     16A  LEU*     3.7    18.9    -      -       -      +
     52A  PHE*     3.9     4.2    -      -       -      -
     57A  ARG*     2.9    16.2    +      -       -      -
     58A  MET      3.2     7.8    +      -       -      -
     60A  ASP*     1.3    73.3    -      -       -      +
     62A  LEU*     1.3    68.9    +      -       -      +
     64A  GLU*     3.3    12.5    +      -       -      +
     65A  PHE*     3.1    22.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 62 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  LEU*     3.8    40.6    -      -       +      +
     19A  LEU*     3.4    39.0    -      -       +      -
     20A  ALA*     4.6     4.9    -      -       +      +
     23A  LEU*     4.2     6.3    -      -       +      -
     58A  MET      2.9     7.8    +      -       -      +
     59A  PHE*     3.1    10.1    +      -       +      +
     61A  SER*     1.3    76.4    -      -       -      +
     63A  ILE*     1.3    63.4    +      -       -      +
     65A  PHE*     3.2    12.7    +      -       +      +
     66A  ILE*     3.0    26.8    +      -       -      +
    105A  LEU*     3.7    21.0    -      -       +      +
    108A  ILE*     3.8    24.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 63 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  PHE*     2.7    24.3    +      -       -      +
     60A  ASP*     3.5     5.4    -      -       -      +
     62A  LEU*     1.3    73.7    -      -       -      +
     64A  GLU*     1.3    62.8    +      -       -      +
     66A  ILE*     3.1     7.7    +      -       -      +
     67A  GLU*     2.9    25.4    +      -       +      +
    108A  ILE*     3.9    23.3    -      -       +      -
    114A  LEU*     4.6     3.8    -      -       +      -
    121A  LEU*     3.7    46.4    -      -       +      +
    124A  ARG*     3.9    31.4    -      -       +      +
    125A  ILE*     4.0    24.2    -      -       +      -
    128A  LEU*     5.5     3.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 64 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60A  ASP*     2.7    18.2    +      -       -      +
     61A  SER*     3.6    12.2    -      -       -      +
     63A  ILE*     1.3    72.1    -      -       -      +
     65A  PHE*     1.3    58.6    +      -       -      +
     67A  GLU*     3.4     5.4    +      -       -      +
     68A  ASP*     2.8    45.2    +      -       -      +
    124A  ARG*     3.1    37.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 65 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  LEU*     6.5     0.2    -      -       +      -
     61A  SER      3.1    13.3    +      -       -      +
     62A  LEU*     3.2    13.7    +      -       +      +
     64A  GLU*     1.3    77.8    -      -       -      +
     66A  ILE*     1.3    53.4    +      -       -      +
     68A  ASP*     3.9     7.0    -      -       +      +
     69A  SER*     2.6    56.2    +      -       -      -
     73A  ARG*     6.0     1.6    -      -       -      -
     98A  PHE*     4.0    10.5    -      +       -      -
    102A  ASN*     4.4     7.0    -      -       -      -
    105A  LEU*     3.6    33.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 66 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62A  LEU      3.0    20.9    +      -       -      +
     63A  ILE*     3.1    11.4    +      -       -      +
     65A  PHE*     1.3    73.2    -      -       -      +
     67A  GLU*     1.3    66.8    +      -       -      +
     69A  SER*     3.8     0.7    -      -       -      -
     70A  LEU*     3.0    33.7    +      -       +      +
     98A  PHE*     4.0    21.8    -      -       +      -
    105A  LEU*     3.8    48.7    -      -       +      +
    108A  ILE*     4.0    20.6    -      -       +      -
    109A  LEU*     4.3    13.0    -      -       +      -
    125A  ILE*     4.8     2.9    -      -       +      -
    128A  LEU*     3.6    21.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 67 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63A  ILE*     2.9    18.5    +      -       +      +
     64A  GLU*     3.8     5.0    -      -       -      +
     66A  ILE*     1.3    72.6    -      -       -      +
     68A  ASP*     1.3    67.4    -      -       -      +
     71A  ILE*     2.7    44.2    +      -       +      +
    124A  ARG*     4.0    19.6    +      -       -      -
    127A  GLN*     5.7     1.0    -      -       -      +
    128A  LEU*     3.7    37.3    -      -       +      +
    131A  ARG*     3.6    29.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 68 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64A  GLU*     2.8    36.2    +      -       -      +
     65A  PHE*     3.9     7.1    +      -       +      +
     67A  GLU*     1.3    79.6    -      -       -      +
     69A  SER*     1.3    64.3    +      -       -      +
     71A  ILE*     4.9     2.2    -      -       -      -
     72A  THR*     2.9    35.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 69 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  PHE*     2.6    51.1    +      -       -      -
     66A  ILE      3.8     0.7    -      -       -      -
     68A  ASP*     1.3    75.6    -      -       -      +
     70A  LEU*     1.3    63.8    +      -       -      +
     72A  THR*     4.1     2.0    -      -       -      -
     73A  ARG*     3.1    38.8    +      -       -      +
     98A  PHE*     3.5    26.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 70 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66A  ILE*     3.0    34.7    +      -       +      +
     67A  GLU*     4.1     1.6    -      -       -      +
     69A  SER*     1.3    78.7    -      -       -      +
     71A  ILE*     1.3    66.9    +      -       +      +
     73A  ARG      3.4     0.9    +      -       -      -
     74A  ILE*     2.9    37.3    +      -       +      +
     94A  LEU*     3.9    24.9    -      -       +      +
     95A  ILE*     4.3    16.4    -      -       +      -
     98A  PHE*     3.7    39.3    -      -       +      -
    109A  LEU*     4.9     9.2    -      -       +      -
    128A  LEU*     4.5     4.9    -      -       +      -
    132A  ILE*     3.9    25.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 71 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67A  GLU*     2.7    27.6    +      -       +      +
     68A  ASP*     4.3     1.6    -      -       -      +
     70A  LEU*     1.3    77.4    -      -       +      +
     72A  THR*     1.3    65.0    +      -       -      +
     74A  ILE*     3.2     8.5    +      -       +      +
     75A  ASN*     3.1    38.8    +      -       -      +
    128A  LEU*     3.6    26.0    -      -       +      -
    131A  ARG*     3.5    53.4    -      -       +      +
    132A  ILE*     4.5    10.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 72 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68A  ASP*     2.9    28.4    +      -       -      +
     69A  SER*     4.1     2.9    -      -       -      -
     71A  ILE*     1.3    79.6    -      -       -      +
     73A  ARG*     1.3    65.1    +      -       +      +
     75A  ASN*     3.5    10.4    +      -       +      +
     76A  LEU*     3.2    35.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 73 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  PHE*     6.0     1.4    -      -       -      -
     69A  SER*     3.1    29.5    +      -       -      +
     72A  THR*     1.3    77.2    -      -       +      +
     74A  ILE*     1.3    67.4    +      -       -      +
     76A  LEU*     3.2    14.7    +      -       +      +
     77A  ILE*     3.0    26.8    +      -       +      +
     94A  LEU*     3.6    35.1    -      -       +      +
     98A  PHE*     3.9    25.4    -      -       -      -
    101A  ARG*     2.7    37.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 74 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70A  LEU*     2.9    31.1    +      -       +      +
     71A  ILE*     3.2    10.9    +      -       +      +
     73A  ARG*     1.3    77.2    -      -       -      +
     75A  ASN*     1.3    64.9    +      -       -      +
     77A  ILE*     3.0     8.1    +      -       +      +
     78A  LEU*     3.0    28.9    +      -       +      +
     91A  ILE*     3.3    50.5    -      -       +      -
     94A  LEU*     3.2    24.2    -      -       +      -
     95A  ILE*     5.3     3.4    -      -       +      -
    132A  ILE*     5.5     8.1    -      -       +      -
    135A  GLN*     4.2    25.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 75 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71A  ILE*     3.1    32.6    +      -       -      +
     72A  THR*     3.8     8.5    -      -       -      +
     74A  ILE*     1.3    77.0    -      -       -      +
     76A  LEU*     1.3    64.0    +      -       +      +
     78A  LEU*     3.1    12.2    +      -       -      +
     79A  LYS*     3.0    25.2    +      -       -      +
    135A  GLN*     4.3    16.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 76 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72A  THR*     3.2    40.7    +      -       +      +
     73A  ARG*     3.4    16.6    -      -       +      +
     74A  ILE      3.2     0.2    -      -       -      -
     75A  ASN*     1.3    76.8    -      -       +      +
     77A  ILE*     1.3    65.2    +      -       +      +
     79A  LYS*     3.3    35.5    -      -       +      +
     80A  ASP*     3.0    33.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 77 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  ARG*     3.0    19.7    +      -       +      +
     74A  ILE*     3.3     7.4    -      -       +      +
     76A  LEU*     1.3    78.3    -      -       +      +
     78A  LEU*     1.3    59.1    +      -       +      +
     80A  ASP*     4.9     2.5    -      -       -      -
     81A  GLU*     2.9    32.0    +      -       +      +
     87A  ARG*     4.0    22.7    -      -       +      +
     90A  LEU*     3.6    60.3    -      -       +      +
     91A  ILE*     3.8    15.3    -      -       +      +
     94A  LEU*     4.2    14.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 78 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74A  ILE*     3.0    24.1    +      -       +      +
     75A  ASN*     3.1    13.9    +      -       -      +
     77A  ILE*     1.3    76.8    -      -       +      +
     79A  LYS*     1.3    60.4    +      -       -      +
     81A  GLU      3.4     2.3    -      -       -      +
     82A  LYS*     3.0    12.3    +      -       -      -
     87A  ARG*     2.8    53.0    +      -       +      +
     91A  ILE*     4.5     8.1    -      -       +      -
    135A  GLN*     3.3    35.7    -      -       -      +
    138A  GLN*     5.4     5.2    -      -       -      +
    139A  VAL*     3.7    20.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 79 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75A  ASN      3.0    13.8    +      -       -      +
     76A  LEU*     3.3    35.0    -      -       +      +
     78A  LEU*     1.3    77.0    -      -       -      +
     80A  ASP*     1.3    89.0    +      -       -      +
     82A  LYS*     3.1    26.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 80 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76A  LEU*     3.0    23.4    +      -       -      +
     77A  ILE*     4.3     2.2    -      -       -      +
     79A  LYS*     1.3   124.9    +      -       -      +
     81A  GLU*     1.3    60.4    +      -       +      +
     82A  LYS*     4.1     4.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 81 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77A  ILE*     2.9    17.0    +      -       +      +
     78A  LEU      3.4     1.4    -      -       -      +
     80A  ASP*     1.3    79.2    -      -       +      +
     82A  LYS*     1.3    63.8    +      -       -      +
     83A  ASP*     2.5    39.5    +      -       -      +
     86A  ALA*     3.4    30.1    -      -       +      +
     87A  ARG*     2.7    34.4    +      -       +      +
     90A  LEU*     3.9    24.5    -      -       +      +
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il