Contacts of the helix formed by residues 73 - 100 (chain A) in PDB entry 1OKC


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 ASN 73 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  LYS      3.7     7.1    +      -       -      -
     23A  THR*     3.1    25.2    +      -       -      +
     26A  ALA*     3.5    21.9    -      -       +      +
     70A  TRP*     3.0    30.6    +      -       +      +
     71A  ARG      3.3     1.4    +      -       -      -
     72A  GLY*     1.3    74.8    -      -       -      +
     74A  LEU*     1.3    67.3    +      -       -      +
     75A  ALA      3.1     2.7    -      -       -      -
     76A  ASN*     2.9    50.7    +      -       -      +
     77A  VAL*     3.3     3.8    +      -       -      +
    137A  ARG*     4.5     2.2    -      -       -      +
    800A  CDL      3.2    19.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 74 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  ASN*     1.3    70.6    -      -       -      +
     75A  ALA*     1.3    64.6    +      -       -      +
     77A  VAL*     3.1    30.2    +      -       +      +
     78A  ILE*     3.2    23.9    +      -       +      +
    156A  LEU*     3.7    13.5    -      -       +      -
    800A  CDL      2.8   100.1    +      -       +      +
    980A  PC1      3.4    24.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 75 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72A  GLY      3.6     4.1    +      -       -      +
     73A  ASN      3.1     0.4    -      -       -      -
     74A  LEU*     1.3    78.3    -      -       -      +
     76A  ASN*     1.3    62.8    +      -       -      +
     78A  ILE*     3.3     3.7    +      -       -      +
     79A  ARG*     3.0    29.6    +      -       -      +
    133A  LEU*     3.4    38.3    -      -       +      +
    137A  ARG*     3.7    19.3    -      -       +      +
    140A  LEU*     6.3     0.2    -      -       +      -
    156A  LEU*     4.1    19.1    -      -       +      +
    800A  CDL      4.3     0.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 76 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  ALA*     5.6     1.0    -      -       -      +
     19A  ALA*     5.2     1.0    -      -       -      -
     22A  LYS*     3.9    45.8    +      -       +      +
     29A  GLU*     3.1    27.4    +      -       -      +
     73A  ASN*     2.9    38.5    +      -       -      +
     75A  ALA*     1.3    80.7    -      -       -      +
     77A  VAL*     1.3    59.0    +      -       +      +
     79A  ARG*     4.0     9.9    +      -       -      +
     80A  TYR*     4.6     4.7    +      -       -      +
    137A  ARG*     3.5    26.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 77 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15A  GLY      4.8     0.5    -      -       -      +
     19A  ALA*     3.9    28.7    -      -       +      +
     23A  THR*     3.4    26.0    -      -       -      +
     73A  ASN*     3.8    11.9    -      -       -      +
     74A  LEU*     3.1    29.6    +      -       +      +
     76A  ASN*     1.3    77.7    -      -       +      +
     78A  ILE*     1.3    64.5    +      -       +      +
     80A  TYR*     4.7     5.2    +      -       -      +
     81A  PHE*     3.5    20.1    -      -       -      -
    800A  CDL      3.8    37.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 78 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74A  LEU*     3.2    39.3    +      -       +      +
     75A  ALA*     3.9     3.6    -      -       -      +
     77A  VAL*     1.3    79.8    -      -       +      +
     79A  ARG*     1.3    66.8    +      -       -      +
     80A  TYR      3.0     4.0    +      -       -      -
     81A  PHE*     3.1    15.0    +      -       +      -
     82A  PRO*     3.1    18.5    -      -       +      +
    133A  LEU*     4.2    20.0    -      -       +      -
    156A  LEU*     4.0    11.4    -      -       +      -
    800A  CDL      5.5     1.6    -      -       +      -
    980A  PC1      3.9    33.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 79 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  LYS*     3.4    20.2    -      -       -      +
     75A  ALA      3.0    16.8    +      -       -      +
     76A  ASN*     4.3     6.1    -      -       -      +
     77A  VAL      3.8     0.2    -      -       -      -
     78A  ILE*     1.3    76.0    -      -       -      +
     80A  TYR*     1.3    63.5    +      -       -      +
     82A  PRO*     3.1     5.1    -      -       -      +
     83A  THR*     2.8    37.9    +      -       -      +
    130A  VAL*     3.8    23.3    -      -       +      -
    133A  LEU*     4.1    17.5    -      -       +      +
    134A  ASP*     3.0    38.8    +      -       -      -
    401A  CXT      2.6    71.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 80 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  ASP      4.4     0.3    +      -       -      -
     11A  PHE*     3.0    46.3    +      +       -      -
     14A  GLY*     3.5    27.3    -      -       -      -
     15A  GLY*     3.2    23.1    -      -       -      +
     18A  ALA*     3.8    20.4    -      -       +      -
     19A  ALA      6.0     0.2    -      -       -      +
     22A  LYS*     5.6     4.1    -      -       -      +
     76A  ASN      4.6     5.4    +      -       -      +
     77A  VAL      4.7     5.6    -      -       -      +
     78A  ILE      3.0     1.3    +      -       -      +
     79A  ARG*     1.3    78.5    -      -       -      +
     81A  PHE*     1.3    72.6    +      +       +      +
     83A  THR*     4.3     4.7    -      -       -      -
     84A  GLN*     2.8    65.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 81 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11A  PHE*     3.5    34.2    -      +       +      -
     12A  LEU*     4.4    18.6    -      -       +      -
     15A  GLY*     3.9    24.5    -      -       -      -
     16A  VAL*     4.9     1.8    -      -       +      -
     77A  VAL      3.5    19.7    -      -       -      -
     78A  ILE*     3.1    18.2    +      -       +      +
     80A  TYR*     1.3    86.6    -      +       -      +
     82A  PRO*     1.3    72.1    -      -       +      +
     85A  ALA*     3.0    23.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 82 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78A  ILE*     3.1    29.4    -      -       +      +
     79A  ARG*     3.1    18.4    -      -       -      +
     81A  PHE*     1.3    80.0    -      -       +      +
     83A  THR*     1.3    61.8    +      -       -      +
     85A  ALA*     3.1     6.4    +      -       +      +
     86A  LEU*     2.8    35.1    +      -       +      +
    129A  PHE*     5.7     2.2    -      -       +      -
    130A  VAL*     3.6    20.4    -      -       +      -
    133A  LEU*     4.4     8.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 83 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     79A  ARG*     2.8    37.4    +      -       -      +
     80A  TYR*     3.6     6.1    -      -       -      -
     82A  PRO*     1.3    78.2    -      -       -      +
     84A  GLN*     1.3    71.7    +      -       -      +
     86A  LEU*     3.2     7.4    +      -       -      +
     87A  ASN*     2.9    27.4    +      -       -      +
    126A  SER*     4.1     9.5    +      -       -      +
    130A  VAL*     3.6    20.5    -      -       -      +
    401A  CXT      4.1    32.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 84 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11A  PHE*     3.6    21.5    -      -       +      -
     80A  TYR*     2.8    57.2    +      -       +      +
     83A  THR*     1.3    80.2    -      -       -      +
     85A  ALA*     1.3    66.7    +      -       -      +
     87A  ASN*     3.6    28.2    +      -       -      +
     88A  PHE*     3.0    23.4    +      -       -      +
    401A  CXT      4.1    11.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 85 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11A  PHE*     4.2    10.3    -      -       +      -
     81A  PHE      3.0    18.8    +      -       -      +
     82A  PRO*     3.1     8.7    +      -       +      +
     84A  GLN*     1.3    76.2    -      -       -      +
     86A  LEU*     1.3    64.9    +      -       +      +
     88A  PHE*     3.2    21.6    +      -       -      +
     89A  ALA*     3.5     6.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 86 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82A  PRO*     2.8    27.1    +      -       +      +
     83A  THR*     3.5     5.2    -      -       -      +
     85A  ALA*     1.3    76.6    -      -       +      +
     87A  ASN*     1.3    64.6    +      -       -      +
     89A  ALA*     3.1     3.9    +      -       -      -
     90A  PHE*     3.0    46.9    +      -       +      +
    125A  THR*     5.3     1.6    -      -       +      +
    126A  SER*     3.8    26.2    -      -       -      +
    129A  PHE*     3.6    58.3    -      -       +      -
    130A  VAL*     4.7     2.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 87 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     83A  THR*     2.9    15.3    +      -       -      +
     84A  GLN*     3.6    29.9    +      -       -      +
     86A  LEU*     1.3    75.7    -      -       -      +
     88A  PHE*     1.3    62.3    +      -       -      +
     90A  PHE*     5.0     0.6    -      -       -      +
     91A  LYS*     2.8    50.8    +      -       +      +
     92A  ASP      4.3     1.4    +      -       -      -
    122A  ALA*     4.4    11.4    -      -       -      +
    126A  SER*     3.4    16.6    +      -       -      -
    401A  CXT      2.9    40.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 88 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7A  PHE*     3.7    41.5    -      +       +      -
     84A  GLN      3.0    12.8    +      -       -      +
     85A  ALA*     3.3    15.0    -      -       -      +
     86A  LEU      3.2     0.4    -      -       -      -
     87A  ASN*     1.3    78.0    -      -       -      +
     89A  ALA*     1.3    61.3    +      -       +      +
     92A  ASP*     5.8     1.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 89 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     85A  ALA      3.5     6.4    +      -       -      +
     86A  LEU*     3.1     7.4    +      -       -      +
     87A  ASN      3.1     0.4    -      -       -      -
     88A  PHE*     1.3    85.1    -      -       +      +
     90A  PHE*     1.3    75.9    +      -       +      +
     92A  ASP      5.7     0.2    -      -       -      -
     93A  LYS*     3.8    19.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 90 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     86A  LEU*     3.0    42.3    +      -       +      +
     87A  ASN*     5.0     0.9    -      -       -      +
     89A  ALA*     1.3    93.8    -      -       +      +
     91A  LYS*     1.3    68.7    +      -       -      +
     92A  ASP      3.4     2.2    -      -       -      -
     93A  LYS*     2.9    19.4    +      -       +      +
     94A  TYR*     3.0    49.2    +      +       +      -
    122A  ALA*     5.5     2.0    -      -       -      -
    125A  THR*     3.9    26.9    -      -       +      -
    129A  PHE*     5.6     4.7    -      +       -      -
----------------------------------------------------------
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Residues in contact with LYS 91 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87A  ASN*     2.8    41.5    +      -       +      +
     90A  PHE*     1.3    74.0    -      -       -      +
     92A  ASP*     1.3    63.0    +      -       -      +
     94A  TYR*     3.4     4.0    +      -       -      +
     95A  LYS*     3.2    50.7    +      -       +      +
    118A  SER*     4.4     1.0    +      -       -      +
    122A  ALA*     4.5    21.6    -      -       +      +
    187A  ARG*     6.2     0.2    -      -       -      +
    401A  CXT      2.7    58.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 92 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87A  ASN      4.3     1.8    +      -       -      -
     88A  PHE      5.8     1.5    +      -       -      +
     90A  PHE      3.4     0.6    -      -       -      -
     91A  LYS*     1.3    76.9    -      -       -      +
     93A  LYS*     1.3    62.2    +      -       +      +
     95A  LYS*     3.1    17.2    +      -       +      +
     96A  GLN*     2.6    60.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 93 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     89A  ALA      3.8    20.9    -      -       -      +
     90A  PHE*     2.9    10.8    +      -       +      +
     92A  ASP*     1.3    78.1    +      -       +      +
     94A  TYR*     1.3    59.4    +      -       +      +
     96A  GLN*     3.3    24.0    +      -       -      +
     97A  ILE*     2.8    42.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 94 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     90A  PHE*     3.0    51.6    +      +       +      -
     91A  LYS      3.8     5.4    -      -       -      +
     92A  ASP      3.3     0.2    -      -       -      -
     93A  LYS*     1.3    77.0    -      -       +      +
     95A  LYS*     1.3    57.8    +      -       -      +
     97A  ILE*     3.2    16.1    +      -       +      -
     98A  PHE*     2.8    49.4    +      +       +      +
    118A  SER*     3.8    15.5    -      -       -      +
    121A  ALA*     3.5    23.8    -      -       +      -
    122A  ALA*     3.6    21.3    -      -       +      -
    125A  THR*     2.7    29.5    +      -       -      +
    802A  CDL      5.2     4.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 95 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91A  LYS*     3.2    44.2    +      -       -      +
     92A  ASP*     3.1    21.4    +      -       -      +
     94A  TYR*     1.3    79.4    -      -       -      +
     96A  GLN*     1.3    54.1    +      -       +      +
     99A  LEU*     2.7    50.9    +      -       +      +
    118A  SER*     3.2    22.7    -      -       -      +
    187A  ARG*     5.3    10.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 96 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     92A  ASP*     2.6    43.4    +      -       -      +
     93A  LYS*     3.6    32.1    -      -       -      +
     95A  LYS*     1.3    76.3    -      -       +      +
     97A  ILE*     1.3    60.3    +      -       +      +
    100A  GLY*     2.8    32.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 97 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     93A  LYS*     2.8    36.7    +      -       +      +
     94A  TYR*     3.6    21.3    -      -       +      +
     96A  GLN*     1.3    79.7    -      -       +      +
     98A  PHE*     1.3    79.7    +      -       +      +
    100A  GLY      4.5     2.9    +      -       -      +
    110A  ARG*     4.9     3.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 98 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     94A  TYR*     2.8    43.6    +      +       -      +
     97A  ILE*     1.3    86.3    -      -       +      +
     99A  LEU*     1.3    63.1    +      -       -      +
    110A  ARG*     2.8    33.5    +      -       -      +
    114A  GLY*     3.5    19.6    -      -       -      +
    117A  ALA*     3.6    24.7    -      -       +      -
    118A  SER*     3.7    15.5    -      -       -      +
    121A  ALA*     3.8    27.4    -      -       +      -
    802A  CDL      5.8     5.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 99 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95A  LYS*     2.7    34.3    +      -       +      +
     96A  GLN*     5.0     0.2    -      -       -      -
     98A  PHE*     1.3    83.3    -      -       +      +
    100A  GLY*     1.3    65.7    +      -       -      +
    101A  GLY      3.2     0.5    +      -       -      -
    102A  VAL*     2.6    43.6    +      -       +      +
    110A  ARG*     4.4     0.9    -      -       -      +
    111A  TYR*     3.5    54.1    -      -       +      +
    114A  GLY*     3.5    13.9    -      -       -      +
    115A  ASN*     4.3    19.3    -      -       -      +
    118A  SER*     5.1     1.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 100 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95A  LYS      3.6     1.6    +      -       -      -
     96A  GLN*     2.8    25.5    +      -       -      +
     97A  ILE      4.5     2.0    +      -       -      +
     98A  PHE      3.8     0.4    -      -       -      -
     99A  LEU*     1.3    79.1    -      -       -      +
    101A  GLY*     1.3    60.1    +      -       -      -
    102A  VAL*     3.4     1.0    +      -       -      +
    110A  ARG*     4.9     6.8    +      -       -      -
----------------------------------------------------------
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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