Contacts of the helix formed by residues 153 - 180 (chain C) in PDB entry 1K6O


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 153 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    151C  ILE*     3.5     6.1    -      -       +      +
    152C  ASP*     1.3    75.0    -      -       -      +
    154C  LYS*     1.3    53.6    +      -       -      +
    155C  LEU*     2.5    36.6    +      -       -      +
    156C  ARG*     2.9    30.4    +      -       +      -
    157C  ARG*     3.4     7.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 154 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152C  ASP      3.0     9.9    +      -       -      +
    153C  ASN*     1.3    67.8    -      -       -      +
    155C  LEU*     1.3    62.7    +      -       -      +
    157C  ARG*     3.6    26.1    +      -       -      +
    158C  TYR*     3.6    17.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 155 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    153C  ASN*     2.5    18.0    +      -       -      +
    154C  LYS*     1.3    71.5    -      -       -      +
    156C  ARG*     1.3    70.5    +      -       -      +
    158C  TYR*     2.9    18.0    +      -       -      +
    159C  THR*     2.8    13.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 156 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    151C  ILE*     4.1    13.7    -      -       +      -
    153C  ASN*     2.9    21.4    +      -       +      +
    155C  LEU*     1.3    73.5    -      -       -      +
    157C  ARG*     1.3    69.3    +      -       -      +
    159C  THR*     2.5    26.9    +      -       -      -
    160C  THR*     2.8    12.1    +      -       -      +
    120D    G      4.7    13.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 157 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    179B  THR*     3.7    29.1    -      -       +      +
    150C  PHE*     3.3    39.0    -      -       +      -
    151C  ILE*     3.5    29.7    +      -       +      +
    152C  ASP*     3.7    13.7    +      -       -      -
    153C  ASN      3.4     2.9    +      -       -      +
    154C  LYS*     3.6    34.5    +      -       -      +
    156C  ARG*     1.3    77.8    -      -       -      +
    158C  TYR*     1.3    55.1    +      -       -      +
    160C  THR*     2.8     3.3    +      -       -      -
    161C  PHE*     2.6    34.0    +      -       +      +
    190C  GLU*     2.6    46.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 158 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    154C  LYS      3.6     9.8    +      -       -      +
    155C  LEU*     2.9    13.1    +      -       -      +
    156C  ARG      2.9     1.0    +      -       -      -
    157C  ARG*     1.3    78.7    -      -       -      +
    159C  THR*     1.3    68.1    +      -       +      +
    161C  PHE*     3.1    15.6    +      +       +      +
    162C  SER*     2.9    45.3    +      -       -      -
    201E    T      3.9    25.2    -      -       +      +
----------------------------------------------------------
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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
----------------------------------------------------------
    155C  LEU*     2.8    11.4    +      -       -      +
    156C  ARG*     2.5    26.5    +      -       -      -
    158C  TYR*     1.3    80.7    -      -       +      +
    160C  THR*     1.3    59.9    -      -       -      +
    162C  SER*     3.6     2.3    +      -       -      -
    163C  LYS*     3.3    35.6    +      -       +      +
    121D    A      6.0     2.0    -      -       -      +
    122D    C      5.3    10.3    -      -       -      +
    201E    T      4.6    22.5    -      -       +      +
    202E    G      5.4     3.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 160 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175B  LEU*     6.1     0.2    -      -       +      -
    178B  LEU*     4.0    21.5    -      -       +      -
    179B  THR*     4.4     8.1    -      -       +      -
    151C  ILE*     3.5    21.6    -      -       +      +
    156C  ARG*     2.8     8.0    +      -       -      +
    157C  ARG      2.8     8.1    +      -       -      -
    159C  THR*     1.3    75.7    -      -       -      +
    161C  PHE*     1.3    67.9    +      -       -      +
    163C  LYS*     2.9    14.4    +      -       -      -
    164C  ARG*     2.9    32.4    +      -       +      +
    119D    G      2.9    34.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 161 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175B  LEU*     4.0    11.4    -      -       +      +
    179B  THR*     3.4    32.7    -      -       +      +
    181B  THR*     3.7    23.8    -      -       +      -
    157C  ARG*     2.6    14.9    +      -       +      +
    158C  TYR*     3.4    19.7    -      +       +      +
    160C  THR*     1.3    73.0    -      -       -      +
    162C  SER*     1.3    66.8    +      -       -      +
    165C  LYS*     3.0    52.7    +      -       +      +
    187C  VAL*     3.5    32.8    -      -       +      -
    189C  SER*     3.8    30.7    -      -       -      -
    195C  TYR*     4.4     6.7    -      +       -      -
----------------------------------------------------------
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Residues in contact with SER 162 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    158C  TYR*     2.9    41.7    +      -       -      -
    159C  THR      4.1     4.0    -      -       -      -
    161C  PHE*     1.3    83.4    -      -       -      +
    163C  LYS*     1.3    61.9    +      -       -      +
    165C  LYS*     3.7     7.1    -      -       -      +
    166C  THR*     3.2    26.0    +      -       -      -
    201E    T      3.9    31.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 163 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    159C  THR*     3.3    20.7    +      -       +      +
    160C  THR*     2.9    10.0    +      -       -      +
    162C  SER*     1.3    76.7    -      -       -      +
    164C  ARG*     1.3    67.0    +      -       +      +
    165C  LYS      3.1     1.3    -      -       -      -
    166C  THR*     3.1     7.6    +      -       -      -
    167C  GLY*     2.9    19.1    +      -       -      -
    118D    A      3.9    37.1    +      -       +      +
    119D    G      4.3    14.1    +      -       +      +
    120D    G      3.6    16.2    +      -       -      -
    121D    A      4.1     4.6    -      -       -      +
    201E    T      6.1     0.4    -      -       -      -
    202E    G      5.0     5.6    +      -       -      -
    203E    T      3.4    38.4    +      -       -      +
    204E    C      4.1     4.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 164 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    171B  LYS*     5.0     5.2    +      -       +      +
    174B  GLU*     3.1    46.2    +      -       -      +
    175B  LEU*     4.3    25.5    -      -       +      +
    178B  LEU*     3.5    21.6    -      -       +      +
    143C  ARG*     3.5    10.7    -      -       -      +
    148C  MET*     4.7     1.0    -      -       -      -
    160C  THR*     2.9    36.2    +      -       +      +
    163C  LYS*     1.3    71.6    -      -       -      +
    165C  LYS*     1.3    54.4    +      -       -      +
    167C  GLY      3.0     0.5    +      -       -      -
    168C  ILE*     2.6    39.1    +      -       +      +
    118D    A      2.8    67.6    +      -       -      +
    119D    G      3.1    14.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 165 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175B  LEU*     4.7     5.5    -      -       +      +
    161C  PHE*     3.0    45.6    +      -       +      +
    162C  SER*     3.7     8.1    -      -       -      +
    163C  LYS      3.1     0.2    -      -       -      -
    164C  ARG*     1.3    77.4    -      -       -      +
    166C  THR*     1.3    66.2    +      -       -      +
    168C  ILE*     3.2     6.8    -      -       -      +
    169C  MET*     3.0    49.6    +      -       +      +
    187C  VAL*     4.5    10.3    -      -       +      -
    195C  TYR*     2.9    58.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 166 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    162C  SER      3.2    11.7    +      -       -      -
    163C  LYS*     3.1     9.5    +      -       -      -
    165C  LYS*     1.3    83.0    -      -       -      +
    167C  GLY*     1.3    58.0    +      -       -      +
    169C  MET*     3.6     5.8    +      -       -      +
    170C  LYS*     3.0    32.2    +      -       +      +
    201E    T      4.9    11.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 167 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    171B  LYS*     6.1     1.6    -      -       -      -
    163C  LYS      2.9    11.1    +      -       -      -
    164C  ARG      3.0     3.3    +      -       -      -
    166C  THR*     1.3    77.6    -      -       -      +
    168C  ILE*     1.3    55.9    -      -       -      +
    170C  LYS*     2.9    27.4    +      -       -      +
    171C  LYS*     2.9    16.8    +      -       -      +
    117D    T      5.3     7.4    +      -       -      +
    118D    A      3.6    20.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 168 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168B  ILE*     3.3    22.4    -      -       +      +
    171B  LYS*     3.7    16.3    -      -       +      +
    172B  ALA*     3.5    39.7    -      -       +      +
    175B  LEU*     4.3    17.3    -      -       +      -
    183B  VAL*     5.1     0.4    -      -       +      -
    185B  LEU*     5.6     0.2    -      -       +      -
    164C  ARG*     2.6    18.2    +      -       +      +
    165C  LYS*     3.2    17.5    -      -       -      +
    167C  GLY*     1.3    71.9    -      -       -      +
    169C  MET*     1.3    66.5    +      -       +      +
    171C  LYS*     2.9    10.6    +      -       -      +
    172C  ALA*     2.8    26.9    +      -       -      +
    185C  LEU*     3.7    26.5    -      -       +      -
    187C  VAL*     5.0     0.2    -      -       +      -
    118D    A      4.8     1.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with MET 169 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    165C  LYS*     3.0    32.0    +      -       +      +
    166C  THR*     3.8     5.8    -      -       -      +
    168C  ILE*     1.3    79.5    -      -       +      +
    170C  LYS*     1.3    68.3    +      -       -      +
    172C  ALA*     3.3     4.5    +      -       -      +
    173C  TYR*     3.1    22.0    +      -       -      +
    185C  LEU*     3.5    35.2    -      -       +      -
    187C  VAL*     4.0    18.6    -      -       +      -
    195C  TYR*     4.2    25.4    -      -       +      +
    196C  THR*     4.3     8.7    -      -       -      +
    197C  PHE*     4.0    24.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 170 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    166C  THR*     3.0    20.3    +      -       +      +
    167C  GLY*     2.9    17.4    +      -       -      +
    169C  MET*     1.3    77.1    -      -       -      +
    171C  LYS*     1.3    54.1    +      -       -      +
    173C  TYR*     3.1    12.7    +      -       +      +
    174C  GLU*     2.9    45.9    +      -       +      +
    117D    T      3.6    35.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 171 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    143B  ARG*     5.8     2.4    -      -       -      +
    164B  ARG*     3.7    23.4    -      -       +      +
    168B  ILE*     3.4    26.0    -      -       +      +
    171B  LYS*     4.5    24.0    -      -       +      +
    167C  GLY      2.9    16.4    +      -       -      +
    168C  ILE*     2.9    13.2    +      -       -      +
    170C  LYS*     1.3    72.5    -      -       +      +
    172C  ALA*     1.3    56.7    +      -       -      +
    173C  TYR      2.8     4.3    -      -       -      -
    174C  GLU*     2.7    13.4    +      -       -      -
    175C  LEU*     2.6    37.5    +      -       +      +
    116D    T      4.7     3.0    +      -       -      -
    117D    T      3.5    28.4    +      -       -      +
    210E    A      3.8    10.9    +      -       -      -
    211E    T      3.3    25.0    +      -       -      +
----------------------------------------------------------
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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
----------------------------------------------------------
    168B  ILE*     4.0     8.6    -      -       +      +
    185B  LEU*     5.4     0.4    -      -       +      -
    168C  ILE      2.8    15.4    +      -       -      +
    169C  MET      3.8     7.2    -      -       -      +
    171C  LYS*     1.3    72.6    -      -       -      +
    173C  TYR*     1.3    57.1    +      -       -      +
    175C  LEU*     4.2     5.5    -      -       -      +
    176C  SER*     2.9    29.3    +      -       -      -
    183C  VAL*     4.0    18.0    -      -       +      +
    185C  LEU*     4.1    17.3    -      -       +      -
    197C  PHE*     3.6    28.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 173 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    148B  MET*     4.8    15.6    +      -       +      +
    169C  MET      3.1    10.6    +      -       -      +
    170C  LYS*     3.1    16.8    +      -       +      +
    171C  LYS      2.7     1.6    +      -       -      -
    172C  ALA*     1.3    76.4    -      -       -      +
    174C  GLU*     1.3    66.8    +      -       +      +
    176C  SER*     4.9     1.3    -      -       -      -
    177C  THR*     2.8    61.8    +      -       +      +
    197C  PHE*     3.8    25.8    -      +       +      -
----------------------------------------------------------
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Residues in contact with GLU 174 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    148B  MET*     3.1    37.5    -      -       +      +
    164B  ARG*     3.2    34.5    +      -       -      +
    170C  LYS*     2.9    38.1    -      -       +      +
    171C  LYS*     2.7    20.2    +      -       -      +
    173C  TYR*     1.3    77.0    -      -       +      +
    175C  LEU*     1.3    56.7    +      -       -      +
    178C  LEU*     2.8    39.1    +      -       -      +
    116D    T      4.9     2.3    -      -       -      +
    117D    T      4.1     6.7    +      -       -      -
----------------------------------------------------------
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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
----------------------------------------------------------
    161B  PHE*     4.3    11.7    -      -       +      +
    164B  ARG*     3.7    34.6    -      -       +      +
    165B  LYS*     4.2     6.3    -      -       -      +
    168B  ILE*     4.1    22.7    -      -       +      -
    187B  VAL*     3.5    36.8    -      -       +      -
    171C  LYS*     2.6    20.3    +      -       +      +
    172C  ALA*     4.2     3.4    -      -       -      +
    174C  GLU*     1.3    71.3    -      -       -      +
    176C  SER*     1.3    66.3    +      -       -      +
    178C  LEU*     4.9     2.0    -      -       -      -
    179C  THR*     2.9    44.8    +      -       +      +
    181C  THR*     4.5     2.2    -      -       -      +
    183C  VAL*     3.9    14.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 176 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    172C  ALA      2.9    23.3    +      -       -      -
    173C  TYR*     3.6     4.6    +      -       -      -
    175C  LEU*     1.3    76.1    -      -       -      +
    177C  THR*     1.3    58.6    +      -       -      +
    180C  GLY*     2.6    40.0    +      -       -      -
    181C  THR      3.2    14.1    +      -       -      -
    183C  VAL*     4.2     4.0    -      -       -      -
    197C  PHE*     4.0     8.8    -      -       -      -
    199C  THR*     3.4    30.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 177 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    148B  MET*     3.2    34.1    -      -       +      +
    149B  GLU*     4.3     7.2    -      -       -      -
    150B  PHE*     4.0    11.6    -      -       -      +
    173C  TYR*     2.8    51.2    +      -       -      +
    176C  SER*     1.3    78.9    +      -       -      +
    178C  LEU*     1.3    67.6    +      -       -      +
    180C  GLY*     3.0    12.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 178 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    146B  ILE*     4.5    13.5    -      -       +      -
    147B  LYS      3.8    16.6    -      -       -      +
    148B  MET*     3.3    20.6    -      -       +      -
    149B  GLU      3.6    20.9    -      -       -      +
    150B  PHE*     3.3     3.6    -      -       -      -
    151B  ILE*     3.1    45.2    +      -       +      +
    160B  THR*     4.4    11.4    -      -       +      -
    164B  ARG*     3.6    41.3    -      -       -      +
    174C  GLU      2.8    28.5    +      -       -      +
    175C  LEU*     5.1     0.2    -      -       -      -
    177C  THR*     1.3    76.3    -      -       -      +
    179C  THR*     1.3    65.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 179 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    150B  PHE*     3.8    11.9    -      -       -      -
    151B  ILE*     5.5     0.4    -      -       +      -
    157B  ARG*     3.9    25.9    -      -       +      +
    160B  THR*     4.7     6.7    -      -       +      -
    161B  PHE*     3.6    37.9    -      -       +      +
    190B  GLU*     4.5     3.1    -      -       -      +
    175C  LEU*     2.9    27.7    +      -       +      +
    178C  LEU*     1.3    84.8    -      -       +      +
    180C  GLY*     1.3    63.5    +      -       -      +
    181C  THR*     3.0    32.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 180 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    150B  PHE*     4.2     9.6    -      -       -      -
    190B  GLU*     6.0     1.6    -      -       -      +
    176C  SER      2.6    20.3    +      -       -      -
    177C  THR*     3.0    10.9    +      -       -      -
    179C  THR*     1.3    74.5    -      -       -      +
    181C  THR*     1.3    57.5    +      -       -      +
    182C  GLN*     4.4     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