Contacts of the helix formed by residues 179 - 206 (chain B) in PDB entry 3H90


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 ASP 179 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    104B  HIS*     4.0    22.5    +      -       -      +
    110B  PRO*     4.6    11.6    -      -       -      +
    111B  MET      5.1     1.0    +      -       -      -
    112B  THR*     4.7    16.5    +      -       -      -
    164B  ILE*     3.7    25.4    -      -       -      +
    178B  ALA*     1.3    81.5    -      -       -      +
    180B  ALA*     1.3    55.9    +      -       -      +
    181B  LEU      3.5     0.2    -      -       -      -
    182B  PHE*     2.9    10.6    +      -       +      +
    183B  ALA*     2.6    42.0    +      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 180 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    101B  GLY      3.8    10.3    -      -       -      +
    104B  HIS*     3.7    22.7    +      -       -      +
    105B  LEU*     3.7    31.2    -      -       +      -
    106B  ILE*     5.8     0.7    -      -       +      -
    178B  ALA*     3.2     9.2    -      -       +      +
    179B  ASP*     1.3    76.4    -      -       -      +
    181B  LEU*     1.3    57.5    +      -       -      +
    182B  PHE      2.9     0.9    +      -       -      -
    183B  ALA*     4.5     2.9    -      -       -      +
    184B  LEU*     2.7    39.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 181 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105B  LEU*     5.4     0.9    -      -       -      +
    177B  ARG*     6.0     5.2    -      -       +      +
    178B  ALA      4.5     5.6    +      -       -      +
    179B  ASP      3.5     0.8    -      -       -      -
    180B  ALA*     1.3    77.4    -      -       -      +
    182B  PHE*     1.3    78.4    +      -       +      +
    184B  LEU*     4.8     8.2    -      -       +      +
    185B  GLY*     3.5    19.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 182 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    161B  ASN*     3.2    36.6    -      -       -      +
    163B  ALA*     4.6    19.3    -      -       +      -
    164B  ILE*     6.3     1.1    -      -       +      -
    178B  ALA      5.4     3.6    -      -       -      +
    179B  ASP*     2.9    12.2    +      -       -      +
    181B  LEU*     1.3   101.6    -      -       +      +
    183B  ALA*     1.3    63.1    +      -       -      +
    184B  LEU      3.2     1.3    -      -       -      -
    185B  GLY*     4.0     0.4    -      -       -      -
    186B  ILE*     3.2    36.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 183 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97B  LEU*     3.1    39.0    -      -       +      +
    100B  THR*     5.5     1.3    -      -       +      -
    101B  GLY*     4.3     9.9    -      -       -      +
    104B  HIS*     4.8     9.4    -      -       +      +
    161B  ASN*     5.5     0.2    -      -       -      +
    179B  ASP*     2.6    30.8    +      -       +      +
    180B  ALA*     4.1     1.3    -      -       -      +
    182B  PHE*     1.3    72.2    -      -       -      +
    184B  LEU*     1.3    58.4    +      -       -      +
    186B  ILE*     5.0     2.9    -      -       -      -
    187B  GLY      3.5    11.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 184 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97B  LEU      4.6     0.7    -      -       -      -
     98B  PHE*     3.7    23.3    -      -       +      -
    101B  GLY*     3.8    14.3    -      -       -      +
    102B  ILE*     3.5    37.7    -      -       +      +
    105B  LEU*     4.7     8.7    -      -       +      -
    180B  ALA      2.7    23.0    +      -       -      +
    181B  LEU*     4.9     8.5    -      -       +      +
    183B  ALA*     1.3    71.8    -      -       -      +
    185B  GLY*     1.3    59.6    +      -       -      +
    186B  ILE      3.2     0.4    -      -       -      -
    187B  GLY*     3.0    16.1    +      -       -      -
    188B  ILE*     3.0    32.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 185 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181B  LEU      3.5    18.7    +      -       -      -
    182B  PHE*     3.5     1.3    +      -       -      -
    184B  LEU*     1.3    85.6    -      -       -      +
    186B  ILE*     1.3    60.2    +      -       -      +
    188B  ILE*     3.8     7.4    +      -       -      +
    189B  TYR*     3.4    22.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 186 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97B  LEU*     4.0    20.6    -      -       +      -
    156B  SER*     5.0     6.5    -      -       -      +
    159B  MET*     3.6    53.4    -      -       +      +
    161B  ASN*     4.3    13.5    -      -       -      +
    182B  PHE*     3.2    22.8    +      -       +      +
    183B  ALA*     5.0     2.2    -      -       -      -
    185B  GLY*     1.3    73.9    -      -       -      +
    187B  GLY*     1.3    62.4    +      -       -      +
    188B  ILE      3.1     0.5    +      -       -      -
    189B  TYR*     3.1     4.4    +      -       -      -
    190B  ILE*     2.8    50.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 187 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     94B  ALA*     3.4    25.5    -      -       -      +
     97B  LEU*     4.2     6.2    -      -       -      +
     98B  PHE*     3.9    14.9    -      -       -      +
    183B  ALA      3.5    10.7    +      -       -      -
    184B  LEU      3.0     8.5    +      -       -      -
    186B  ILE*     1.3    79.5    -      -       -      +
    188B  ILE*     1.3    58.4    +      -       -      +
    191B  LEU*     3.2    25.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 188 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     98B  PHE*     3.6    33.0    -      -       +      -
    184B  LEU*     3.0    26.4    +      -       +      +
    185B  GLY*     4.0     9.2    -      -       -      +
    187B  GLY*     1.3    74.3    -      -       -      +
    189B  TYR*     1.3    64.2    +      -       +      +
    191B  LEU*     3.1     8.3    +      -       -      +
    192B  TYR*     2.9    33.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 189 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152B  LEU*     5.9     1.3    -      -       +      -
    155B  GLN*     5.4     5.3    +      -       +      -
    159B  MET*     4.1    26.7    -      -       +      -
    185B  GLY      3.4    14.8    +      -       -      +
    186B  ILE*     3.1     4.3    +      -       -      +
    188B  ILE*     1.3    82.3    -      -       +      +
    190B  ILE*     1.3    76.5    +      -       +      +
    192B  TYR*     3.7    12.8    +      +       -      +
    193B  SER*     3.0    49.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 190 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     90B  ILE*     3.9    24.0    -      -       +      +
     93B  SER*     6.4     0.2    -      -       -      -
     94B  ALA*     3.8    17.0    -      -       +      -
    152B  LEU*     4.3    19.2    -      -       +      +
    155B  GLN*     4.7     2.9    -      -       +      -
    156B  SER*     4.1    33.9    -      -       -      +
    159B  MET*     4.3     6.5    -      -       -      -
    186B  ILE*     2.8    41.1    +      -       +      +
    189B  TYR*     1.3    91.9    -      -       +      +
    191B  LEU*     1.3    54.6    +      -       -      +
    193B  SER*     3.1     2.4    +      -       -      -
    194B  ALA*     2.7    34.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 191 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91B  SER*     3.3    41.0    +      -       -      +
     94B  ALA*     3.4    10.2    -      -       +      +
     95B  LEU*     4.5    25.1    -      -       +      +
     98B  PHE*     5.7     7.4    -      -       +      -
    187B  GLY      3.2    21.1    +      -       -      +
    188B  ILE*     3.1     5.5    +      -       -      +
    190B  ILE*     1.3    76.1    -      -       -      +
    192B  TYR*     1.3    62.9    +      -       -      +
    194B  ALA*     3.4     3.3    +      -       -      -
    195B  LEU*     3.1    44.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 192 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188B  ILE*     2.9    21.5    +      -       +      +
    189B  TYR*     3.8    13.7    -      +       -      +
    191B  LEU*     1.3    76.8    -      -       -      +
    193B  SER*     1.3    69.8    +      -       -      +
    195B  LEU*     3.3     8.4    +      -       -      +
    196B  ARG*     3.1    51.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 193 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152B  LEU*     3.7    25.8    -      -       -      +
    189B  TYR*     3.0    40.6    +      -       -      -
    190B  ILE*     3.1     5.4    +      -       -      -
    192B  TYR*     1.3    86.4    -      -       -      +
    194B  ALA*     1.3    57.4    +      -       -      +
    196B  ARG*     4.1     5.6    -      -       -      +
    197B  MET*     3.1    25.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 194 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87B  SER*     2.6    32.8    +      -       -      +
     90B  ILE*     3.8    27.1    -      -       +      -
     91B  SER*     3.6    27.2    +      -       -      +
    152B  LEU*     3.6     8.7    -      -       +      +
    190B  ILE      2.7    19.4    +      -       -      +
    191B  LEU      3.9     1.1    -      -       -      +
    192B  TYR      3.2     0.4    -      -       -      -
    193B  SER*     1.3    71.6    -      -       -      +
    195B  LEU*     1.3    59.1    +      -       -      +
    197B  MET*     3.6     4.0    -      -       -      +
    198B  GLY      3.3     5.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 195 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87B  SER*     4.8     1.1    -      -       -      +
     91B  SER*     3.5    17.5    -      -       -      +
    191B  LEU*     3.1    39.2    +      -       +      +
    192B  TYR*     3.9     5.8    -      -       -      +
    194B  ALA*     1.3    76.1    -      -       -      +
    196B  ARG*     1.3    66.0    +      -       -      +
    197B  MET      3.0     1.6    -      -       -      -
    198B  GLY*     3.0     2.4    +      -       -      -
    199B  TYR*     2.9    26.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 196 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    192B  TYR*     3.1    45.3    +      -       +      +
    193B  SER*     4.1     5.8    -      -       -      +
    195B  LEU*     1.3    75.3    -      -       -      +
    197B  MET*     1.3    61.1    +      -       -      +
    199B  TYR*     3.9    34.5    +      -       -      +
    200B  GLU*     3.5    37.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 197 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     83B  ALA*     4.2    11.9    -      -       +      +
     87B  SER*     4.1    16.2    -      -       -      -
     90B  ILE*     6.3     0.4    -      -       +      -
    145B  GLN*     3.6    25.8    -      -       +      +
    148B  ARG*     3.9    33.9    -      -       -      +
    149B  ALA*     3.8    28.9    -      -       +      +
    152B  LEU*     4.3    13.0    -      -       +      -
    193B  SER      3.1    22.6    +      -       -      +
    194B  ALA*     3.6     8.7    -      -       -      +
    196B  ARG*     1.3    77.3    -      -       -      +
    198B  GLY*     1.3    62.9    +      -       -      +
    199B  TYR      3.4     0.3    +      -       -      -
    200B  GLU*     3.5    11.3    +      -       -      +
    201B  ALA*     3.3    17.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 198 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84B  LEU*     3.4     6.8    -      -       -      +
     87B  SER*     3.1    26.7    -      -       -      -
    194B  ALA      3.3     4.2    +      -       -      -
    195B  LEU*     3.0     6.4    +      -       -      -
    197B  MET*     1.3    78.2    -      -       -      +
    199B  TYR*     1.3    59.1    +      -       -      +
    201B  ALA*     3.3     8.7    +      -       -      +
    202B  VAL*     3.0    32.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 199 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    195B  LEU      2.9    16.0    +      -       -      +
    196B  ARG*     4.0    33.4    -      -       -      +
    198B  GLY*     1.3    73.9    -      -       -      +
    200B  GLU*     1.3    66.4    +      -       +      +
    202B  VAL*     2.9    18.2    +      -       +      +
    203B  GLN*     2.8    65.6    +      -       +      +
    208B  ARG*     4.9     6.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 200 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    145B  GLN*     3.7    10.4    +      -       -      +
    148B  ARG*     2.8    38.2    +      -       -      +
    196B  ARG*     3.5    30.6    +      -       +      +
    197B  MET*     3.5    11.5    +      -       -      +
    199B  TYR*     1.3    84.9    -      -       +      +
    201B  ALA*     1.3    61.6    +      -       -      +
    203B  GLN*     3.5     8.6    +      -       -      +
    204B  SER*     3.1    26.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 201 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80B  SER*     3.5    23.3    -      -       -      +
     83B  ALA*     4.2     9.9    -      -       +      -
     84B  LEU*     3.8    17.5    -      -       +      +
    145B  GLN*     4.1    12.5    -      -       -      +
    197B  MET      3.3    10.0    +      -       -      +
    198B  GLY*     3.3    11.7    -      -       -      +
    199B  TYR      3.0     0.4    -      -       -      -
    200B  GLU*     1.3    77.3    -      -       -      +
    202B  VAL*     1.3    62.9    +      -       -      +
    204B  SER*     3.3     4.2    +      -       -      -
    205B  LEU*     3.1    27.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 202 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84B  LEU*     3.6    26.0    -      -       +      -
    198B  GLY      3.0    14.0    +      -       -      +
    199B  TYR*     2.9    32.3    +      -       +      +
    201B  ALA*     1.3    67.0    -      -       -      +
    203B  GLN*     1.3    67.8    +      -       +      +
    204B  SER      3.0     1.8    -      -       -      -
    205B  LEU*     2.8    10.1    +      -       -      +
    206B  LEU*     2.8    41.6    +      -       +      +
     81D  LEU*     3.9    17.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 203 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    199B  TYR*     2.8    58.6    +      -       +      +
    200B  GLU*     3.6     9.0    -      -       -      +
    202B  VAL*     1.3    79.5    -      -       +      +
    204B  SER*     1.3    53.7    +      -       -      +
    206B  LEU*     2.5    33.3    -      -       -      +
    208B  ARG*     2.6    63.5    +      -       -      +
     62D  TYR*     4.5     4.6    +      -       -      -
     71D  HIS*     3.0    25.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 204 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77B  LYS*     3.3    21.4    -      -       -      -
     80B  SER*     3.8    17.5    -      -       -      -
    145B  GLN*     4.0    12.4    +      -       -      -
    200B  GLU      3.1    16.1    +      -       -      -
    201B  ALA      3.7     5.4    -      -       -      -
    202B  VAL      3.0     0.4    -      -       -      -
    203B  GLN*     1.3    73.5    -      -       -      +
    205B  LEU*     1.3    59.5    +      -       -      +
    206B  LEU      2.9    13.8    -      -       -      +
    207B  ASP*     4.2     1.9    -      -       -      -
    208B  ARG*     4.7     2.9    +      -       -      +
    238B  GLN*     4.8    14.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 205 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77B  LYS*     3.7    20.5    +      -       +      +
     80B  SER*     4.1    21.5    -      -       -      +
     81B  LEU*     3.6    30.3    -      -       +      -
     84B  LEU*     3.6    31.4    -      -       +      -
    201B  ALA      3.1    17.2    +      -       -      +
    202B  VAL*     2.8     7.5    +      -       -      +
    204B  SER*     1.3    75.9    -      -       -      +
    206B  LEU*     1.3    63.3    +      -       -      +
    207B  ASP      3.7     0.2    +      -       -      -
     77D  LYS*     3.5    30.7    +      -       -      +
     81D  LEU*     3.9    20.0    -      -       +      -
    205D  LEU*     4.3    17.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 206 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    202B  VAL*     2.8    24.7    +      -       +      +
    203B  GLN*     2.5    50.7    -      -       -      +
    204B  SER      2.9     6.8    -      -       -      +
    205B  LEU*     1.3    73.3    -      -       -      +
    207B  ASP*     1.3    53.7    +      -       -      +
    208B  ARG      2.6     6.8    +      -       -      -
     62D  TYR*     4.3    23.1    -      -       +      -
     71D  HIS*     4.2    14.8    -      -       +      +
     75D  HIS*     5.3     6.7    -      -       -      +
     77D  LYS*     3.9     9.9    -      -       +      -
     78D  ALA*     3.6    29.6    -      -       +      +
     81D  LEU*     3.4    26.7    -      -       +      -
----------------------------------------------------------
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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