Contacts of the helix formed by residues 158 - 184 (chain B) in PDB entry 3KDH


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 THR 158 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68A  LYS*     5.3     1.5    +      -       -      +
     92A  PRO*     5.9     0.8    -      -       -      +
    153B  ILE*     4.2     2.7    -      -       -      -
    156B  GLY      5.1     2.7    -      -       -      +
    157B  ASN*     1.3    78.4    -      -       -      +
    159B  GLU*     1.3    60.8    +      -       -      +
    160B  GLU*     3.7     6.5    +      -       -      +
    161B  ASP*     3.0    41.0    +      -       -      +
    162B  THR*     2.7    33.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 159 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31B  ASP      5.2     0.9    -      -       -      +
     32B  PRO*     5.1     5.7    -      -       -      +
     34B  THR      3.6    13.9    -      -       -      +
     35B  CYS*     4.3    12.3    -      -       +      -
     36B  THR      5.4     0.3    +      -       -      -
    153B  ILE*     3.6    33.7    -      -       +      +
    158B  THR*     1.3    73.2    -      -       -      +
    160B  GLU*     1.3    66.1    +      -       +      +
    162B  THR*     3.8     1.4    -      -       -      -
    163B  LYS*     3.0    26.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 160 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    158B  THR*     3.3     6.4    -      -       -      +
    159B  GLU*     1.3    80.8    -      -       +      +
    161B  ASP*     1.3    64.9    +      -       -      +
    163B  LYS*     3.4     8.8    +      -       -      +
    164B  MET*     3.0    27.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 161 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68A  LYS*     2.8    39.9    +      -       -      +
     88A  ILE*     3.3    41.0    -      -       +      +
     89A  SER      5.3     1.3    -      -       -      -
     92A  PRO*     6.2     1.3    -      -       +      -
     93A  ALA*     3.8    17.8    +      -       +      +
    157B  ASN*     5.7     1.3    -      -       -      +
    158B  THR*     3.0    29.5    +      -       -      +
    160B  GLU*     1.3    79.5    -      -       -      +
    162B  THR*     1.3    60.3    +      -       -      +
    164B  MET      3.4     0.2    +      -       -      -
    165B  PHE*     3.0    23.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 162 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     89A  SER      5.3     1.1    -      -       -      -
     35B  CYS*     4.5     7.2    -      -       +      -
    121B  LEU*     4.2    24.7    -      -       +      -
    151B  VAL*     4.3    20.0    -      -       +      -
    152B  ASP      4.8     0.9    -      -       -      +
    153B  ILE*     4.0     6.8    -      -       -      +
    154B  PRO*     4.4     5.6    -      -       +      -
    157B  ASN*     3.1    28.3    +      -       -      +
    158B  THR      2.7    22.8    +      -       -      -
    159B  GLU*     3.8     5.2    -      -       -      -
    161B  ASP*     1.3    76.5    -      -       -      +
    163B  LYS*     1.3    62.8    +      -       -      +
    165B  PHE*     3.3     6.9    +      -       +      +
    166B  VAL*     3.0    27.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 163 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35B  CYS*     3.2    26.5    -      -       -      -
     36B  THR      2.7    29.7    +      -       -      -
     37B  SER*     3.3    16.0    +      -       -      +
    149B  TYR*     3.3     5.3    +      -       -      +
    159B  GLU*     3.0    18.4    +      -       +      +
    160B  GLU*     3.5     8.7    -      -       -      +
    162B  THR*     1.3    76.9    -      -       -      +
    164B  MET*     1.3    57.5    +      -       -      +
    167B  ASP*     2.8    48.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 164 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66A  PHE*     6.0     5.2    -      -       +      -
     67A  VAL      6.1     1.3    -      -       -      +
     88A  ILE*     3.6    24.9    -      -       +      -
    160B  GLU      3.0    17.4    +      -       -      +
    161B  ASP*     3.7     5.2    -      -       -      +
    162B  THR      3.3     0.2    -      -       -      -
    163B  LYS*     1.3    75.3    -      -       -      +
    165B  PHE*     1.3    60.8    +      -       -      +
    167B  ASP*     4.4     9.0    -      -       -      +
    168B  THR*     2.7    45.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 165 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66A  PHE*     3.7    27.1    -      +       -      -
     88A  ILE*     3.6     7.4    -      -       +      +
     89A  SER*     3.4    37.9    -      -       -      +
     90A  GLY*     3.7    24.2    -      -       -      -
    121B  LEU*     3.9    16.4    -      -       +      -
    161B  ASP      3.0    14.4    +      -       -      +
    162B  THR*     3.6     4.5    -      -       +      +
    163B  LYS      3.3     0.2    -      -       -      -
    164B  MET*     1.3    78.8    -      -       -      +
    166B  VAL*     1.3    74.4    +      -       +      +
    168B  THR*     3.2     4.3    +      -       -      -
    169B  VAL*     3.1    39.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 166 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121B  LEU*     4.1    17.7    -      -       +      -
    124B  TYR*     3.9    16.4    -      -       +      -
    149B  TYR*     3.5    40.6    -      -       +      +
    151B  VAL*     4.4    16.2    -      -       +      -
    162B  THR*     3.0    15.6    +      -       +      +
    165B  PHE*     1.3    87.3    -      -       +      +
    167B  ASP*     1.3    66.2    +      -       -      +
    168B  THR      3.2     0.3    +      -       -      -
    169B  VAL*     3.3     6.3    +      -       +      +
    170B  VAL*     2.9    27.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 167 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37B  SER*     2.8    26.5    +      -       -      -
     39B  ILE*     3.5    21.7    -      -       +      +
    149B  TYR*     2.7    26.7    +      -       -      -
    163B  LYS*     2.8    38.9    +      -       -      +
    164B  MET*     3.8    10.3    -      -       -      +
    166B  VAL*     1.3    72.7    -      -       -      +
    168B  THR*     1.3    57.8    +      -       -      +
    170B  VAL*     4.0     0.7    -      -       -      +
    171B  LYS*     3.0    31.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 168 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  HIS*     4.0    20.6    -      -       +      +
     66A  PHE*     3.6    33.5    +      -       +      +
    164B  MET*     2.7    37.0    +      -       -      +
    165B  PHE      3.6     4.5    -      -       -      -
    166B  VAL      3.2     0.2    -      -       -      -
    167B  ASP*     1.3    76.0    -      -       -      +
    169B  VAL*     1.3    65.7    +      -       -      +
    171B  LYS*     3.8     4.4    -      -       -      +
    172B  LEU*     3.0    40.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 169 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66A  PHE*     4.2    12.8    -      -       +      -
     66B  PHE*     5.4    18.2    -      -       +      -
    165B  PHE*     3.1    42.1    +      -       +      +
    166B  VAL*     3.8     9.2    -      -       +      +
    168B  THR*     1.3    76.5    -      -       -      +
    170B  VAL*     1.3    66.8    +      -       +      +
    172B  LEU*     3.2     8.8    +      -       -      +
    173B  ASN*     3.0    38.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 170 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39B  ILE*     3.7    27.8    -      -       +      -
    124B  TYR*     3.6    24.2    -      -       -      +
    147B  GLU*     3.7    34.1    -      -       +      +
    149B  TYR*     4.3     7.2    -      -       +      -
    166B  VAL*     2.9    30.2    +      -       +      +
    167B  ASP      4.0     2.7    -      -       -      +
    169B  VAL*     1.3    80.1    -      -       +      +
    171B  LYS*     1.3    64.2    +      -       -      +
    173B  ASN*     3.2     9.2    +      -       -      +
    174B  LEU*     3.0    23.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 171 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9B  GLY*     6.1     2.2    -      -       -      -
     39B  ILE*     3.9    16.3    -      -       +      +
     40B  THR*     2.8    29.1    +      -       -      +
     41B  GLN*     2.9    25.9    +      -       -      +
     42B  ARG      5.2     0.6    -      -       -      +
    167B  ASP      3.0    18.8    +      -       -      +
    168B  THR*     3.8     5.6    -      -       -      +
    170B  VAL*     1.3    79.0    -      -       -      +
    172B  LEU*     1.3    58.0    +      -       +      +
    174B  LEU*     3.1     4.0    +      -       +      +
    175B  GLN*     2.9    49.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 172 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  HIS*     3.4    37.7    -      -       +      +
     66A  PHE*     4.4     8.5    -      -       +      -
    172A  LEU*     3.9    31.9    -      -       +      +
     65B  HIS*     3.7    23.8    +      -       +      -
     66B  PHE*     6.0     1.3    -      -       +      -
    168B  THR*     3.0    38.0    +      -       +      +
    169B  VAL*     3.2     6.5    +      -       -      +
    171B  LYS*     1.3    77.9    -      -       +      +
    173B  ASN*     1.3    63.4    +      -       -      +
    175B  GLN*     3.3    26.9    +      -       -      +
    176B  LYS      3.0    17.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 173 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63B  TYR*     2.9    23.6    -      -       +      +
     64B  LYS*     3.7    34.0    -      -       +      +
     65B  HIS*     2.9    34.0    +      -       -      +
     66B  PHE*     5.6     0.2    -      -       -      -
    147B  GLU*     6.0     0.9    -      -       -      +
    169B  VAL*     3.0    32.0    +      -       -      +
    170B  VAL*     3.6    10.4    -      -       -      +
    172B  LEU*     1.3    78.7    -      -       -      +
    174B  LEU*     1.3    58.2    +      -       +      +
    176B  LYS*     3.1     1.5    +      -       -      -
    177B  LEU*     2.9    26.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 174 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39B  ILE*     4.0    32.1    -      -       +      +
     40B  THR      4.3     1.1    -      -       -      -
     41B  GLN*     3.6    38.2    -      -       +      +
     63B  TYR*     4.6     7.0    -      -       +      -
    128B  THR*     5.4     1.1    -      -       +      -
    145B  VAL*     4.0    23.3    -      -       +      +
    147B  GLU*     3.4    36.8    -      -       +      +
    170B  VAL*     3.0    16.2    +      -       +      +
    171B  LYS      3.1     6.5    +      -       -      +
    173B  ASN*     1.3    77.4    -      -       +      +
    175B  GLN*     1.3    57.4    +      -       -      +
    177B  LEU*     3.3    17.7    +      -       +      +
    178B  GLY      2.9    22.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 175 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  HIS*     5.5     2.5    -      -       -      -
    179A  VAL*     6.0     3.7    -      -       -      +
     41B  GLN*     3.3    24.7    -      -       -      +
    171B  LYS*     2.9    41.9    +      -       -      +
    172B  LEU*     3.5    29.1    -      -       -      +
    173B  ASN      3.2     0.2    -      -       -      -
    174B  LEU*     1.3    77.1    -      -       -      +
    176B  LYS*     1.3    61.3    +      -       -      +
    178B  GLY*     3.2     2.9    +      -       -      -
    179B  VAL*     3.0    26.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 176 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61B  GLU      2.9    29.4    +      -       -      -
     62B  ARG*     3.5    12.3    -      -       -      +
     63B  TYR*     3.4    23.3    -      -       -      +
     64B  LYS      3.1    14.7    +      -       -      +
     65B  HIS*     3.7    39.6    +      -       +      +
    172B  LEU      3.0     6.2    +      -       -      +
    173B  ASN      3.1     1.8    +      -       -      +
    175B  GLN*     1.3    73.5    -      -       -      +
    177B  LEU*     1.3    66.8    +      -       -      +
    179B  VAL*     3.2     9.9    +      -       +      +
    180B  ALA*     3.0    22.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 177 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43B  ILE*     3.9    18.8    -      -       +      -
     50B  VAL*     4.1     9.2    -      -       +      +
     53B  LEU*     3.6    36.3    -      -       +      -
     54B  ILE*     3.8    28.0    -      -       +      -
     63B  TYR*     3.5    27.2    -      -       +      +
    145B  VAL*     4.0    10.3    -      -       +      -
    173B  ASN      2.9    12.9    +      -       -      +
    174B  LEU*     3.3    24.7    -      -       +      +
    176B  LYS*     1.3    76.3    -      -       -      +
    178B  GLY*     1.3    61.2    +      -       -      +
    180B  ALA*     3.3     3.4    +      -       -      +
    181B  ALA*     3.0    23.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 178 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41B  GLN*     5.4     2.0    -      -       -      -
     43B  ILE*     3.6    28.5    -      -       -      -
    174B  LEU      2.9    13.4    +      -       -      -
    175B  GLN*     3.2     5.5    +      -       -      -
    177B  LEU*     1.3    76.4    -      -       -      +
    179B  VAL*     1.3    61.1    +      -       -      +
    181B  ALA*     3.4     0.5    +      -       -      -
    182B  THR*     2.9    32.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 179 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175B  GLN      3.0    15.8    +      -       -      +
    176B  LYS*     3.2    10.9    +      -       +      +
    178B  GLY*     1.3    74.0    -      -       -      +
    180B  ALA*     1.3    65.2    +      -       -      +
    182B  THR*     3.3     6.2    +      -       -      -
    183B  SER*     2.8    42.3    +      -       -      +
    184B  ALA*     6.2     0.4    -      -       +      -
----------------------------------------------------------
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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
----------------------------------------------------------
     49B  VAL*     5.4     0.3    -      -       -      +
     53B  LEU*     4.1    19.7    -      -       +      -
     62B  ARG*     4.1    22.1    +      -       -      +
     63B  TYR*     5.4     0.2    -      -       +      -
    176B  LYS*     3.0    15.7    +      -       +      +
    177B  LEU*     3.7     5.6    -      -       -      +
    178B  GLY      3.2     0.4    -      -       -      -
    179B  VAL*     1.3    78.6    -      -       -      +
    181B  ALA*     1.3    59.8    +      -       -      +
    184B  ALA*     3.0    45.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 181 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43B  ILE*     4.1     6.1    -      -       +      -
     45B  ALA*     3.7     8.0    -      -       +      +
     49B  VAL*     3.5    27.7    -      -       +      +
     50B  VAL*     3.7    30.3    -      -       +      -
     53B  LEU*     3.8    16.3    -      -       +      +
    177B  LEU      3.0    16.6    +      -       -      +
    178B  GLY      4.0     2.9    -      -       -      +
    180B  ALA*     1.3    78.6    -      -       -      +
    182B  THR*     1.3    59.3    +      -       -      +
    184B  ALA      5.2     1.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 182 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43B  ILE*     3.8    17.9    -      -       +      -
     44B  HIS*     3.6    30.5    -      -       +      +
     45B  ALA*     4.6     2.7    -      -       -      -
    178B  GLY      2.9    26.3    +      -       -      +
    179B  VAL*     3.3     9.2    +      -       -      +
    181B  ALA*     1.3    78.5    -      -       -      +
    183B  SER*     1.3    65.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 183 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    179B  VAL*     2.8    33.1    +      -       -      +
    181B  ALA      3.5     0.6    -      -       -      -
    182B  THR*     1.3    84.9    -      -       -      +
    184B  ALA*     1.3    64.0    +      -       -      +
    185B  PRO*     4.1     3.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 184 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49B  VAL*     6.1     0.9    -      -       -      +
     62B  ARG*     4.5     7.5    +      -       -      +
    179B  VAL*     4.8     0.7    -      -       +      +
    180B  ALA*     3.0    32.6    +      -       +      +
    181B  ALA      5.3     1.4    -      -       -      +
    183B  SER*     1.3    81.3    +      -       -      +
    185B  PRO*     1.3    80.5    -      -       +      +
    186B  MET*     3.5     5.4    +      -       -      +
----------------------------------------------------------
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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