Contacts of the helix formed by residues 95 - 119 (chain C) in PDB entry 5DIR


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 GLU 95 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91C  LEU*     4.2    10.8    -      -       +      +
     92C  LYS*     3.4    48.0    +      -       +      +
     93C  LYS      3.3     3.0    -      -       -      -
     94C  GLY*     1.3    75.6    -      -       -      +
     96C  THR*     1.3    62.8    +      -       -      +
     97C  TRP      3.5     2.8    +      -       -      -
     98C  LEU*     3.5    24.7    +      -       +      +
     99C  ALA*     3.3    21.1    +      -       -      +
    156C  ASP*     5.8     0.2    -      -       -      +
    159C  ARG*     3.2    32.7    +      -       -      +
     90D  ARG*     3.5    12.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 96 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12C  TRP*     5.6    12.5    +      -       +      +
     94C  GLY*     3.3    20.2    +      -       -      +
     95C  GLU*     1.3    72.7    -      -       -      +
     97C  TRP*     1.3    67.1    +      -       -      +
     99C  ALA*     3.3     6.7    +      -       -      +
    100C  ILE*     3.1    37.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 97 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95C  GLU*     3.5     0.8    -      -       +      -
     96C  THR*     1.3    83.5    +      -       -      +
     98C  LEU*     1.3    66.2    +      -       -      +
    100C  ILE*     3.4     7.2    +      -       +      +
    101C  ALA*     3.4    15.8    +      -       -      +
    152C  MET*     3.0    72.2    +      -       +      +
    155C  LEU*     4.5    24.1    +      -       +      -
    156C  ASP*     4.1    19.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 98 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87C  TRP*     3.9    35.2    -      -       +      +
     91C  LEU*     3.9    21.3    -      -       +      -
     95C  GLU*     3.5    34.3    +      -       +      +
     96C  THR      3.4     0.2    -      -       -      -
     97C  TRP*     1.3    82.6    -      -       +      +
     99C  ALA*     1.3    62.8    +      -       -      +
    101C  ALA*     3.3     4.2    +      -       +      +
    102C  LEU*     3.2    37.6    +      -       +      +
    153C  LEU*     4.5    11.2    -      -       +      -
    156C  ASP*     4.0    32.7    +      -       +      +
     90D  ARG*     4.5    13.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 99 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12C  TRP*     4.6    21.8    -      -       +      +
     88C  LEU*     4.0    11.5    -      -       +      +
     91C  LEU*     3.6    21.0    -      -       +      +
     95C  GLU      3.3    12.6    +      -       -      +
     96C  THR*     3.6    12.1    -      -       -      +
     97C  TRP      3.3     0.2    -      -       -      -
     98C  LEU*     1.3    78.7    -      -       -      +
    100C  ILE*     1.3    61.8    +      -       -      +
    102C  LEU*     3.3     4.3    +      -       -      +
    103C  ALA*     3.1    22.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 100 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12C  TRP*     5.3     7.4    -      -       +      +
     15C  ILE*     4.0    30.2    -      -       +      +
     96C  THR*     3.1    25.2    +      -       -      +
     97C  TRP*     3.7    11.0    -      -       +      +
     98C  LEU      3.3     0.2    -      -       -      -
     99C  ALA*     1.3    77.3    -      -       +      +
    101C  ALA*     1.3    63.6    +      -       -      +
    103C  ALA*     3.4     3.0    +      -       -      +
    104C  LEU*     3.1    37.5    +      -       +      +
    152C  MET*     3.7    19.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 101 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97C  TRP      3.4     6.3    +      -       -      +
     98C  LEU*     3.3    10.9    +      -       -      +
     99C  ALA      3.3     0.4    -      -       -      -
    100C  ILE*     1.3    80.3    -      -       -      +
    102C  LEU*     1.3    61.6    -      -       -      +
    104C  LEU*     3.5     0.6    +      -       -      -
    105C  VAL*     3.1    28.9    +      -       -      +
    149C  GLY*     3.5    10.3    -      -       -      +
    152C  MET*     3.5    34.7    -      -       +      +
    153C  LEU*     3.5    23.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 102 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84C  LEU*     3.9    17.4    -      -       +      +
     87C  TRP*     3.7    55.9    -      -       +      -
     88C  LEU*     3.9    34.8    -      -       +      +
     91C  LEU*     4.3     9.4    -      -       +      -
     98C  LEU*     3.2    20.5    +      -       +      +
     99C  ALA      3.8     5.8    -      -       -      +
    100C  ILE      3.3     0.2    -      -       -      -
    101C  ALA*     1.3    74.8    -      -       -      +
    103C  ALA*     1.3    56.2    +      -       -      +
    105C  VAL*     3.1     6.2    +      -       -      +
    106C  LEU*     2.8    39.0    +      -       +      +
    153C  LEU*     3.8    17.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 103 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12C  TRP      5.5     1.8    -      -       -      +
     13C  LEU*     5.3     6.7    -      -       -      -
     15C  ILE*     3.9    25.4    -      -       +      -
     16C  THR*     2.8    33.6    +      -       -      +
     88C  LEU*     4.7     8.8    -      -       +      +
     99C  ALA      3.1    16.5    +      -       -      +
    100C  ILE*     3.4     5.6    +      -       -      +
    102C  LEU*     1.3    76.6    -      -       -      +
    104C  LEU*     1.3    57.0    +      -       -      +
    106C  LEU*     4.4     3.1    -      -       -      -
    107C  GLY*     2.8    19.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 104 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15C  ILE*     3.9    13.5    -      -       +      -
     19C  VAL*     3.6    26.0    -      -       +      -
    100C  ILE*     3.1    27.8    +      -       +      +
    101C  ALA      3.7     4.7    -      -       -      +
    103C  ALA*     1.3    77.0    -      -       -      +
    105C  VAL*     1.3    58.0    +      -       -      +
    107C  GLY*     3.3     1.0    +      -       -      -
    108C  GLY      2.8    24.4    +      -       -      -
    145C  ALA*     3.3    27.2    -      -       +      +
    148C  VAL*     4.0    28.3    -      -       +      -
    149C  GLY*     4.3     3.4    -      -       -      +
    152C  MET*     4.1    13.9    -      -       -      -
    204C  OLC      6.3     4.7    -      -       +      -
    301F  OLC      4.1    20.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 105 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80C  VAL*     5.6     0.2    -      -       +      -
     84C  LEU*     3.7    22.4    -      -       +      -
    101C  ALA      3.1    17.9    +      -       -      +
    102C  LEU*     3.1     6.1    +      -       -      +
    104C  LEU*     1.3    72.5    -      -       -      +
    106C  LEU*     1.3    60.4    +      -       -      +
    108C  GLY*     3.4     0.5    +      -       -      -
    109C  ALA*     2.8    27.9    +      -       -      +
    146C  ILE*     3.9    21.1    -      -       +      +
    149C  GLY*     3.7    25.6    -      -       -      +
    150C  ALA*     3.8     6.5    -      -       +      +
    153C  LEU*     4.6     6.3    -      -       +      -
    201F  MLE      4.2    20.4    -      -       +      -
    302F  OLC      5.1     9.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 106 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13C  LEU*     6.2     1.1    -      -       +      -
     16C  THR*     3.6    19.1    -      -       +      +
     81C  SER*     4.5    10.3    -      -       -      +
     84C  LEU*     4.1    16.6    -      -       +      +
     85C  VAL*     3.7    32.5    -      -       +      +
     88C  LEU*     4.5    17.9    -      -       +      -
    102C  LEU*     2.8    17.1    +      -       +      +
    103C  ALA*     3.8     3.8    -      -       -      +
    105C  VAL*     1.3    76.6    -      -       -      +
    107C  GLY*     1.3    57.5    +      -       -      +
    109C  ALA*     3.2     4.9    +      -       -      +
    110C  LEU*     2.9    55.2    +      -       +      +
    202C  OLC      5.9     0.4    -      -       +      -
    203C  OLC      4.4    15.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 107 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16C  THR*     3.7    26.2    -      -       -      +
     19C  VAL*     3.7    14.6    -      -       -      +
     20C  PHE*     4.2     7.0    -      -       -      -
     23C  ASP*     5.6     0.3    -      -       -      +
    103C  ALA      2.8    17.4    +      -       -      -
    104C  LEU      3.7     1.3    -      -       -      -
    106C  LEU*     1.3    78.2    -      -       -      +
    108C  GLY*     1.3    60.2    +      -       -      +
    110C  LEU*     3.5     3.1    +      -       -      +
    111C  GLY*     3.1    20.1    +      -       -      -
    142C  ALA*     5.0     0.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 108 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19C  VAL*     3.8     2.1    -      -       -      +
    104C  LEU      2.8    13.3    +      -       -      -
    107C  GLY*     1.3    72.6    -      -       -      +
    109C  ALA*     1.3    65.1    +      -       -      +
    111C  GLY      3.4     0.2    +      -       -      -
    112C  ASN*     3.4    11.8    +      -       -      -
    142C  ALA*     3.3    48.5    -      -       -      +
    145C  ALA*     4.4     1.1    -      -       -      -
    146C  ILE*     3.6    15.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 109 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77C  ALA*     4.3     5.9    -      -       +      +
     81C  SER*     3.6    18.6    -      -       -      +
     84C  LEU*     5.3     3.1    -      -       +      -
    105C  VAL*     2.8    19.3    +      -       +      +
    106C  LEU*     3.4     8.1    -      -       -      +
    108C  GLY*     1.3    77.2    -      -       -      +
    110C  LEU*     1.3    57.8    +      -       -      +
    112C  ASN*     3.6     2.1    +      -       -      +
    113C  LEU*     3.1    28.0    +      -       -      +
    146C  ILE*     3.8     7.3    -      -       -      +
    201F  MLE      3.9    29.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 110 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16C  THR*     4.4     3.1    -      -       +      -
     20C  PHE*     3.5    10.7    -      -       +      -
     81C  SER*     3.8    19.3    -      -       -      +
    106C  LEU*     2.9    39.1    +      -       +      +
    107C  GLY*     4.1     2.0    -      -       -      +
    109C  ALA*     1.3    74.8    -      -       -      +
    111C  GLY*     1.3    60.5    +      -       -      +
    113C  LEU*     3.5    14.7    -      -       +      +
    114C  TYR*     2.9    31.5    +      -       -      +
    202C  OLC      3.6    60.5    -      -       +      +
    203C  OLC      4.0    23.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 111 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20C  PHE*     3.7    10.0    -      -       -      -
     23C  ASP*     3.4    23.3    -      -       -      -
     24C  GLN*     3.0    26.4    +      -       -      -
    107C  GLY      3.1    13.9    +      -       -      -
    108C  GLY      3.4     3.3    +      -       -      -
    109C  ALA      3.3     0.4    -      -       -      -
    110C  LEU*     1.3    78.0    -      -       -      +
    112C  ASN*     1.3    60.0    +      -       -      +
    115C  ASP*     3.3    14.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 112 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27C  LYS*     3.1    21.1    +      -       -      -
    108C  GLY      3.4     9.4    +      -       -      +
    109C  ALA      4.3     1.1    -      -       -      +
    111C  GLY*     1.3    73.3    -      -       -      +
    113C  LEU*     1.3    61.8    +      -       -      +
    115C  ASP*     3.2     7.7    +      -       -      +
    116C  ARG*     3.0    42.5    +      -       -      +
    122C  VAL*     3.5    12.4    -      -       +      +
    140C  ASN*     3.3     8.0    +      -       -      -
    142C  ALA*     3.3    16.3    -      -       -      +
    143C  ASP*     3.0    26.7    +      -       -      -
    146C  ILE*     4.2     1.8    -      -       -      +
    201F  MLE      3.1    27.0    +      -       -      +
    202F  IIL      3.8     1.2    -      -       -      -
    203F  SER      3.7     3.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 113 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74C  ALA*     3.5    40.6    -      -       +      +
     77C  ALA*     4.0    12.8    -      -       +      +
     78C  ILE*     4.0    12.6    -      -       +      +
    109C  ALA      3.1    18.9    +      -       -      +
    110C  LEU*     3.5    22.9    -      -       +      +
    111C  GLY      3.3     0.2    -      -       -      -
    112C  ASN*     1.3    76.7    -      -       -      +
    114C  TYR*     1.3    62.9    +      -       -      +
    116C  ARG*     3.1     8.9    +      -       -      +
    117C  MET*     3.0    36.8    +      -       +      +
    202C  OLC      4.2    12.6    -      -       +      -
    203C  OLC      3.8    30.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 114 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20C  PHE*     3.9    16.2    -      +       +      -
     24C  GLN*     3.3    35.4    -      -       +      +
    110C  LEU      2.9    17.7    +      -       -      +
    111C  GLY      3.5     4.3    -      -       -      +
    113C  LEU*     1.3    76.1    -      -       -      +
    115C  ASP*     1.3    66.8    +      -       -      +
    117C  MET*     4.1     0.2    -      -       -      +
    118C  VAL*     3.0    60.5    +      -       +      +
    119C  LEU*     5.6     3.4    -      -       +      -
    202C  OLC      3.6    36.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 115 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24C  GLN*     3.6    20.1    +      -       -      +
     27C  LYS*     2.5    37.3    +      -       -      +
    111C  GLY      3.3     7.1    +      -       -      -
    112C  ASN*     3.2     9.8    +      -       -      +
    113C  LEU      3.1     0.8    -      -       -      -
    114C  TYR*     1.3    83.9    -      -       -      +
    116C  ARG*     1.3    58.3    +      -       -      +
    119C  LEU*     2.8    52.5    +      -       +      +
    120C  GLY      3.1     5.0    +      -       -      -
    121C  HIS      3.2    15.9    -      -       -      +
    122C  VAL*     3.9     6.9    -      -       -      +
    123C  VAL      3.6    10.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 116 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54C  ASN      5.2     2.2    +      -       -      -
     55C  THR      6.3     1.0    -      -       -      -
     56C  GLY*     5.9     0.8    -      -       -      +
     69C  GLN      4.3     1.2    +      -       -      -
     70C  ARG*     2.9    60.4    +      -       +      +
     73C  PHE*     3.5    36.2    +      -       -      +
     74C  ALA*     3.9    12.8    -      -       +      +
     77C  ALA*     5.8     1.2    -      -       -      +
    112C  ASN*     3.0    23.2    +      -       -      +
    113C  LEU*     3.1     8.5    +      -       -      +
    115C  ASP*     1.3    77.1    -      -       -      +
    117C  MET*     1.3    58.7    +      -       -      +
    120C  GLY*     3.3     3.8    -      -       -      -
    121C  HIS*     4.0    12.6    -      -       -      +
    122C  VAL*     3.6    20.9    -      -       +      +
    201F  MLE      3.5    20.8    +      -       -      -
    202F  IIL      3.0    12.5    +      -       -      -
    203F  SER      2.8    28.9    +      -       -      -
    204F  ALO      4.1     0.2    -      -       -      -
    205F  5BV      3.6    12.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with MET 117 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70C  ARG*     2.9    13.0    +      -       -      +
     71C  TRP*     3.9    18.6    -      -       +      -
     74C  ALA*     3.8    24.5    -      -       +      -
     78C  ILE*     5.1     9.4    -      -       +      -
    113C  LEU*     3.0    26.0    +      -       +      +
    114C  TYR      4.1     0.7    -      -       -      +
    115C  ASP      3.2     0.2    -      -       -      -
    116C  ARG*     1.3    78.2    -      -       -      +
    118C  VAL*     1.3    58.9    +      -       -      +
    202C  OLC      3.7    29.4    -      -       +      -
    203C  OLC      2.8    82.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 118 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70C  ARG*     4.7     1.4    +      -       -      -
    114C  TYR*     3.0    56.4    +      -       +      +
    117C  MET*     1.3    79.8    -      -       -      +
    119C  LEU*     1.3    75.0    +      -       +      +
    202C  OLC      3.7    53.2    +      -       +      +
    203C  OLC      4.5     1.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 119 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27C  LYS*     6.3     0.4    -      -       +      -
     31C  GLN*     5.5     6.1    -      -       +      +
     70C  ARG*     4.9     1.1    -      -       -      -
    114C  TYR*     5.6     3.6    -      -       +      -
    115C  ASP*     2.8    42.6    +      -       -      +
    118C  VAL*     1.3    88.9    -      -       +      +
    120C  GLY*     1.3    54.2    +      -       -      +
    121C  HIS*     3.3    39.2    +      -       +      +
    123C  VAL*     3.7    25.8    -      -       +      -
----------------------------------------------------------
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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