Contacts of the helix formed by residues 155 - 181 (chain C) in PDB entry 2AXT


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 155 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    153C  ASP*     2.3    28.0    +      -       -      +
    154C  LYS*     1.3    71.0    -      -       -      +
    156C  LYS*     1.3    60.8    +      -       -      +
    157C  MET      2.8     6.3    +      -       -      -
    158C  THR*     2.9    12.9    +      -       -      -
    159C  THR*     2.7    18.0    +      -       -      +
    251C  HIS      4.7     1.2    +      -       -      -
    252C  ILE      5.8     1.2    +      -       -      -
    254C  THR      3.2    24.1    +      -       -      +
    255C  THR*     3.0    17.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 156 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    148C  GLY      5.3     2.2    -      -       -      +
    149C  TYR*     4.8    11.2    -      -       +      -
    150C  ASP      4.7    10.1    -      -       -      +
    153C  ASP*     2.9    35.2    +      -       +      +
    155C  ASN*     1.3    73.1    -      -       -      +
    157C  MET*     1.3    57.3    +      -       -      +
    159C  THR*     3.3    10.1    -      -       -      -
    160C  ILE*     2.9    36.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with MET 157 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    149C  TYR*     5.0     6.3    -      -       +      -
    150C  ASP      3.6    18.2    -      -       -      +
    151C  TRP*     3.3    51.1    -      -       +      +
    153C  ASP      3.4    17.3    -      -       -      +
    154C  LYS*     5.0     0.7    -      -       -      -
    155C  ASN      2.8     1.3    -      -       -      +
    156C  LYS*     1.3    77.4    -      -       -      +
    158C  THR*     1.3    59.1    +      -       -      +
    159C  THR      2.8    10.3    +      -       -      -
    160C  ILE*     3.1    13.4    +      -       +      +
    161C  LEU*     2.9    26.3    +      -       -      +
    271C  TYR*     4.2    13.5    -      -       +      -
    497C  CLA      3.7    49.7    -      -       +      +
    499C  CLA      6.2     0.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 158 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    154C  LYS      3.5     4.2    +      -       -      -
    155C  ASN*     2.9     9.7    +      -       -      -
    157C  MET*     1.3    76.6    -      -       -      +
    159C  THR*     1.3    55.7    +      -       -      +
    161C  LEU*     4.2     7.6    -      -       +      -
    162C  GLY      3.2     9.0    +      -       -      -
    251C  HIS*     2.9    78.6    -      -       +      +
    254C  THR      3.3    19.3    -      -       -      +
    255C  THR*     4.7     1.8    -      -       -      +
    256C  PRO*     3.4    27.7    -      -       -      +
    496C  CLA      4.9     5.9    -      -       +      +
    497C  CLA      3.9     9.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 159 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    146C  PHE*     5.2     6.1    -      -       +      -
    155C  ASN*     2.7    22.2    +      -       -      -
    156C  LYS*     3.3    14.2    -      -       -      -
    157C  MET      2.8     1.4    +      -       -      -
    158C  THR*     1.3    76.5    -      -       -      +
    160C  ILE*     1.3    65.7    -      -       +      -
    161C  LEU      3.1     1.3    -      -       -      -
    162C  GLY*     2.9    12.5    +      -       -      -
    163C  PHE*     3.0    40.3    +      -       +      -
    251C  HIS      4.8     0.7    +      -       -      -
    252C  ILE*     3.6    28.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 160 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    149C  TYR*     4.1    25.4    -      -       +      -
    156C  LYS*     2.9    20.4    -      -       +      +
    157C  MET*     3.1    13.9    +      -       +      +
    159C  THR*     1.3    73.2    -      -       -      +
    161C  LEU*     1.3    69.0    +      -       -      +
    163C  PHE*     3.2    13.1    +      -       +      +
    164C  HIS*     3.2    53.5    +      -       +      +
    497C  CLA      4.3     9.9    -      -       +      -
    502C  CLA      4.0    45.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 161 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    157C  MET      2.9    16.7    +      -       -      +
    158C  THR*     3.9     7.0    -      -       -      +
    160C  ILE*     1.3    76.1    -      -       -      +
    162C  GLY*     1.3    53.6    +      -       -      +
    164C  HIS*     3.1     7.5    +      -       -      +
    165C  LEU*     2.7    41.1    +      -       +      +
    251C  HIS*     4.1    17.3    -      -       +      +
    496C  CLA      3.9    51.6    -      -       +      -
    497C  CLA      3.3    69.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 162 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    158C  THR      3.2     9.3    +      -       -      -
    159C  THR      2.9     9.7    +      -       -      -
    161C  LEU*     1.3    80.1    -      -       -      +
    163C  PHE*     1.3    61.5    +      -       -      -
    165C  LEU*     3.2     2.2    +      -       -      -
    166C  ILE*     3.0     9.4    +      -       -      +
    248C  GLY*     3.0    48.0    -      -       -      -
    251C  HIS*     3.9     5.6    -      -       -      -
    252C  ILE*     3.8     4.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 163 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    146C  PHE*     3.7    27.8    -      +       -      -
    159C  THR*     3.0    43.0    +      -       +      -
    160C  ILE*     3.2    15.7    +      -       +      +
    162C  GLY*     1.3    72.6    -      -       -      +
    164C  HIS*     1.3    53.1    +      -       +      +
    166C  ILE*     2.6    35.3    +      -       +      +
    167C  VAL*     2.8    19.6    +      -       -      +
    252C  ILE*     3.3    30.5    -      -       +      -
    502C  CLA      3.3    67.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 164 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    160C  ILE*     3.2    35.6    +      -       +      +
    161C  LEU      3.4     6.7    -      -       -      +
    163C  PHE*     1.3    78.5    -      -       -      +
    165C  LEU*     1.3    58.0    +      -       -      +
    167C  VAL*     2.9     8.4    +      -       +      +
    168C  LEU*     2.8    34.1    +      -       +      +
    497C  CLA      2.8    45.2    +      -       -      +
    502C  CLA      3.0    75.6    +      +       +      -
----------------------------------------------------------
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Residues in contact with LEU 165 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    161C  LEU*     2.7    31.5    +      -       +      +
    162C  GLY      3.3    11.4    -      -       -      +
    163C  PHE      3.2     0.2    -      -       -      -
    164C  HIS*     1.3    73.6    -      -       -      +
    166C  ILE*     1.3    58.0    +      -       -      +
    168C  LEU*     4.0     3.3    +      -       +      -
    169C  GLY      3.5    12.6    +      -       -      -
    244C  CYS*     3.0    59.5    -      -       -      +
    247C  GLY      4.3     2.5    -      -       -      +
    248C  GLY*     3.4     7.2    -      -       -      +
    251C  HIS*     3.3    34.3    -      -       +      -
    496C  CLA      3.5    50.3    -      -       +      -
    497C  CLA      3.8     5.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 166 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    162C  GLY      3.0    16.8    -      -       -      +
    163C  PHE*     2.6    20.0    +      -       +      +
    165C  LEU*     1.3    71.2    -      -       -      +
    167C  VAL*     1.3    63.5    +      -       +      +
    168C  LEU      3.2     0.4    -      -       -      -
    169C  GLY*     3.0     2.3    +      -       -      -
    170C  ILE*     2.9    31.8    +      -       +      +
    245C  ILE*     3.4    26.6    -      -       +      +
    248C  GLY*     3.5    15.7    -      -       -      +
    249C  ILE*     3.8    17.0    -      -       +      -
    252C  ILE*     3.6    24.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 167 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    163C  PHE      2.8    15.2    +      -       -      +
    164C  HIS*     3.3    13.0    -      -       -      +
    166C  ILE*     1.3    78.4    -      -       +      +
    168C  LEU*     1.3    63.2    +      -       +      +
    170C  ILE*     3.3     9.1    +      -       -      +
    171C  GLY      3.2     9.9    +      -       -      -
    502C  CLA      3.1   107.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 168 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    164C  HIS*     2.8    17.4    +      -       +      +
    165C  LEU*     4.1     7.6    -      -       -      +
    167C  VAL*     1.3    72.9    -      -       +      +
    169C  GLY*     1.3    58.5    +      -       -      +
    171C  GLY*     2.9     5.4    +      -       -      -
    172C  ALA*     2.8    26.0    +      -       -      +
    244C  CYS*     4.4    11.0    -      -       -      -
    491C  CLA      3.6    37.4    -      -       +      +
    492C  CLA      6.2     1.6    -      -       +      -
    493C  CLA      5.9     3.4    -      -       +      -
    496C  CLA      5.1     0.9    -      -       +      -
    497C  CLA      3.3    72.0    -      -       +      +
    499C  CLA      5.3     8.1    -      -       +      -
    502C  CLA      3.7    12.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 169 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    165C  LEU      3.5     6.3    +      -       -      -
    166C  ILE      3.0     8.0    +      -       -      -
    168C  LEU*     1.3    78.9    -      -       -      +
    170C  ILE*     1.3    61.4    +      -       -      +
    172C  ALA*     3.2     5.2    +      -       -      +
    173C  LEU*     3.0    27.7    +      -       -      +
    241C  GLY*     4.1    11.2    -      -       -      -
    244C  CYS*     4.3     6.2    -      -       -      +
    245C  ILE*     3.7    24.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 170 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    166C  ILE*     2.9    26.2    +      -       +      +
    167C  VAL*     3.6    10.1    -      -       -      +
    168C  LEU      3.3     0.2    -      -       -      -
    169C  GLY*     1.3    74.7    -      -       -      +
    171C  GLY*     1.3    64.4    +      -       -      +
    173C  LEU*     3.3    11.2    +      -       +      +
    174C  LEU*     3.0    32.2    +      -       +      +
    245C  ILE*     4.3    13.2    -      -       +      +
    502C  CLA      4.1    15.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 171 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    167C  VAL      3.2     4.2    +      -       -      -
    168C  LEU      2.9     8.9    +      -       -      -
    170C  ILE*     1.3    77.4    -      -       -      +
    172C  ALA*     1.3    66.3    +      -       -      +
    174C  LEU*     3.0    23.3    +      -       -      +
    175C  LEU*     3.5     3.5    +      -       -      +
    491C  CLA      3.3     8.0    -      -       -      +
    492C  CLA      3.6     9.9    -      -       -      +
    502C  CLA      3.7    28.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 172 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168C  LEU      2.8    14.1    +      -       -      +
    169C  GLY      3.6     7.9    -      -       -      +
    171C  GLY*     1.3    70.7    -      -       -      +
    173C  LEU*     1.3    64.9    +      -       -      +
    175C  LEU*     2.9    23.0    +      -       -      +
    176C  VAL*     3.5     7.6    +      -       -      +
    237C  HIS*     4.3    17.7    -      -       +      +
    240C  ILE*     4.0    22.0    -      -       +      -
    241C  GLY      4.7     1.8    -      -       -      +
    491C  CLA      3.1    29.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 173 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    169C  GLY      3.0    18.0    +      -       -      +
    170C  ILE*     3.6    11.2    -      -       +      +
    171C  GLY      3.2     0.2    -      -       -      -
    172C  ALA*     1.3    75.8    -      -       -      +
    174C  LEU*     1.3    62.5    +      -       -      +
    176C  VAL*     3.2    13.3    +      -       +      +
    177C  ALA*     3.0    20.3    +      -       -      +
    237C  HIS      4.4     4.3    -      -       -      +
    238C  ILE*     4.1    33.9    -      -       +      +
    241C  GLY*     4.5     6.5    -      -       -      -
    242C  LEU*     4.6    16.6    -      -       +      -
    245C  ILE*     4.2    20.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 174 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    170C  ILE*     3.0    28.4    +      -       +      +
    171C  GLY*     3.0    22.5    +      -       -      +
    173C  LEU*     1.3    77.5    -      -       -      +
    175C  LEU*     1.3    61.0    +      -       -      +
    177C  ALA*     3.0    11.9    +      -       +      +
    178C  LYS*     3.0    18.2    +      -       -      +
    492C  CLA      3.8    38.8    -      -       +      +
    493C  CLA      4.3    14.6    -      -       +      -
    502C  CLA      4.1    17.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 175 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95C  LEU*     3.7    29.6    -      -       +      -
    171C  GLY      3.5     2.3    +      -       -      +
    172C  ALA      2.9    11.7    +      -       -      +
    174C  LEU*     1.3    78.4    -      -       -      +
    176C  VAL*     1.3    65.0    +      -       -      +
    178C  LYS*     2.9    15.2    +      -       -      +
    179C  ALA*     3.0    11.9    +      -       +      +
    185C  LEU*     4.7    10.5    -      -       +      -
    233C  VAL*     4.7     6.3    -      -       +      +
    234C  VAL*     5.6     3.8    -      -       +      -
    237C  HIS*     3.5    46.7    -      -       +      +
    491C  CLA      3.9    44.9    -      -       +      +
    492C  CLA      3.7    10.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 176 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    172C  ALA      3.9    12.3    -      -       -      +
    173C  LEU*     3.2    17.9    +      -       +      +
    175C  LEU*     1.3    75.9    -      -       -      +
    177C  ALA*     1.3    53.2    +      -       -      +
    179C  ALA*     3.3     0.8    +      -       -      -
    180C  MET*     2.7    63.3    +      -       +      +
    181C  PHE*     5.0     3.8    -      -       +      -
    234C  VAL*     3.9    13.5    -      -       +      +
    237C  HIS*     4.0     8.7    -      -       +      -
    238C  ILE*     3.4    44.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 177 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    173C  LEU      3.0    11.3    +      -       -      +
    174C  LEU*     3.0    18.3    +      -       +      +
    175C  LEU      2.9     0.2    -      -       -      -
    176C  VAL*     1.3    72.9    -      -       -      +
    178C  LYS*     1.3    59.7    +      -       -      +
    179C  ALA      3.0     4.5    -      -       -      -
    181C  PHE*     2.7    43.3    +      -       +      -
    182C  PHE*     2.9    26.5    +      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 178 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95C  LEU*     2.7    36.1    +      -       +      +
     96C  GLY      3.2    15.6    +      -       -      -
     97C  TRP*     3.3    48.2    -      -       +      +
    174C  LEU      3.0     5.0    +      -       -      +
    175C  LEU*     2.9     8.3    +      -       -      +
    177C  ALA*     1.3    76.0    -      -       -      +
    179C  ALA*     1.3    55.9    -      -       -      +
    182C  PHE*     2.5    53.8    +      -       +      +
    183C  GLY*     4.1     4.9    -      -       -      -
    184C  GLY      2.9    27.3    +      -       -      +
    185C  LEU*     4.2     7.2    -      -       +      -
    492C  CLA      3.5    31.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 179 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175C  LEU*     3.0    11.8    +      -       +      +
    176C  VAL*     3.7     4.0    -      -       -      +
    177C  ALA      3.0     2.0    -      -       -      -
    178C  LYS*     1.3    78.7    -      -       -      +
    180C  MET*     1.3    63.2    +      -       -      +
    181C  PHE      3.3     1.0    +      -       -      -
    184C  GLY*     3.2    25.6    +      -       -      -
    185C  LEU*     3.6    28.0    -      -       +      -
    198C  VAL*     3.4    12.0    -      -       -      +
    199C  ILE*     3.5    10.0    +      -       +      -
    234C  VAL*     3.9    21.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 180 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176C  VAL*     2.7    46.8    +      -       +      +
    179C  ALA*     1.3    72.2    -      -       -      +
    181C  PHE*     1.3    91.6    +      -       +      +
    198C  VAL*     4.0    11.2    -      -       -      +
    199C  ILE      3.2    19.4    -      -       -      +
    200C  THR*     4.6     9.8    -      -       +      +
    202C  PRO*     3.1    42.2    -      -       +      -
    234C  VAL*     4.0     7.0    -      -       +      -
    238C  ILE*     3.8     7.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 181 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176C  VAL*     4.8     2.7    -      -       +      -
    177C  ALA*     2.7    34.3    +      -       +      +
    179C  ALA      3.3     1.0    -      -       -      -
    180C  MET*     1.3   117.6    -      -       +      +
    182C  PHE*     1.3    79.9    +      +       +      +
    183C  GLY      3.7     4.1    +      -       -      -
    184C  GLY      5.2     0.2    -      -       -      -
    198C  VAL*     5.5     3.2    -      -       -      +
----------------------------------------------------------
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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