Contacts of the helix formed by residues 145 - 169 (chain B) in PDB entry 3BUN


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 SER 145 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    139B  ARG*     2.6    30.4    +      -       -      -
    142B  GLU*     2.8    29.4    +      -       -      -
    143B  GLU      3.3     0.6    +      -       -      -
    144B  ASN*     1.3    78.7    -      -       -      +
    146B  GLN*     1.3    65.1    +      -       -      +
    147B  PRO*     3.5     9.5    -      -       -      +
    148B  ARG*     3.0    16.3    +      -       -      +
    149B  ARG*     3.0    14.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 146 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    139B  ARG*     5.3     3.8    -      -       -      +
    144B  ASN      3.9     1.4    +      -       -      -
    145B  SER*     1.3    71.0    -      -       -      +
    147B  PRO*     1.3    71.1    -      -       +      +
    149B  ARG*     3.0    31.2    +      -       -      +
    150B  ASN*     2.9    42.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 147 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132B  LEU*     3.4    26.6    -      -       +      +
    136B  GLY*     4.3     8.1    -      -       -      -
    139B  ARG*     3.5    51.4    -      -       +      +
    140B  MET*     3.7    22.3    -      -       -      +
    145B  SER*     3.2    15.0    -      -       -      +
    146B  GLN*     1.3    96.9    -      -       +      +
    148B  ARG*     1.3    60.0    +      -       -      +
    150B  ASN*     3.4     3.3    +      -       -      +
    151B  LEU      3.2    15.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 148 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75B  LEU*     2.7    48.5    +      -       -      +
     76B  ALA      4.6     0.8    +      -       -      -
     77B  LEU*     4.1    19.8    -      -       -      +
     78B  LYS*     4.5     6.3    -      -       -      +
    140B  MET*     2.9    32.3    +      -       -      +
    141B  TYR*     4.1     8.3    +      -       -      +
    142B  GLU      4.1     7.2    -      -       -      +
    143B  GLU*     3.6    34.7    +      -       -      +
    144B  ASN      4.9     0.2    -      -       -      +
    145B  SER*     3.0    19.2    +      -       -      +
    147B  PRO*     1.3    78.7    -      -       -      +
    149B  ARG*     1.3    65.8    +      -       -      +
    151B  LEU*     3.0    31.3    +      -       -      +
    152B  THR*     3.1    19.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 149 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    143B  GLU*     5.8     1.6    -      -       -      +
    144B  ASN*     2.9    43.1    +      -       -      +
    145B  SER      3.0    13.8    +      -       -      +
    146B  GLN*     3.0    37.4    +      -       -      +
    148B  ARG*     1.3    75.2    -      -       +      +
    150B  ASN*     1.3    58.6    +      -       -      +
    152B  THR*     3.1    10.3    +      -       -      -
    153B  LYS*     3.0    27.9    +      -       -      +
    276B  GLU*     4.8    14.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 150 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132B  LEU*     3.9    23.2    -      -       +      +
    146B  GLN*     2.9    38.7    +      -       -      +
    147B  PRO*     3.6     8.4    -      -       -      +
    149B  ARG*     1.3    78.2    -      -       -      +
    151B  LEU*     1.3    56.5    +      -       -      +
    153B  LYS*     3.4    11.2    +      -       -      +
    154B  LEU*     3.0    37.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 151 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70B  CYS*     4.3    11.4    -      -       -      -
     75B  LEU*     4.1    11.7    -      -       +      -
     77B  LEU*     5.6     7.4    -      -       +      -
     84B  ILE*     5.6     4.7    -      -       +      -
    129B  THR*     4.0    18.2    -      -       +      -
    132B  LEU*     3.5    14.3    -      -       +      +
    133B  PHE*     3.9    37.7    -      -       +      -
    140B  MET*     3.9    12.1    -      -       +      -
    147B  PRO      3.2     3.0    +      -       -      -
    148B  ARG*     3.0    31.2    +      -       -      +
    150B  ASN*     1.3    77.2    -      -       -      +
    152B  THR*     1.3    58.7    +      -       -      +
    154B  LEU*     3.4     5.0    +      -       +      +
    155B  SER*     2.8    38.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 152 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82B  PRO*     5.4     0.4    -      -       +      -
    148B  ARG*     3.1    21.0    +      -       -      +
    149B  ARG*     3.1    11.7    +      -       -      -
    151B  LEU*     1.3    75.9    -      -       -      +
    153B  LYS*     1.3    64.7    +      -       -      +
    155B  SER*     3.2    10.2    +      -       -      -
    156B  LEU*     3.0    21.3    +      -       -      +
    271B  PHE      5.7     0.2    -      -       -      +
    273B  THR*     3.6    17.3    -      -       +      +
    276B  GLU*     3.5    39.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 153 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    149B  ARG      3.0    14.5    +      -       -      +
    150B  ASN*     3.8    11.9    -      -       -      +
    151B  LEU      3.3     0.2    -      -       -      -
    152B  THR*     1.3    76.2    -      -       -      +
    154B  LEU*     1.3    59.0    +      -       +      +
    156B  LEU*     3.2     9.2    +      -       -      +
    157B  ILE*     2.8    43.3    +      -       +      +
    232B  CYS*     4.3     9.7    -      -       -      -
    271B  PHE*     3.5    59.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 154 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84B  ILE*     6.1     0.2    -      -       +      -
    125B  LYS*     4.2    14.1    -      -       +      +
    128B  GLN*     4.1    24.5    -      -       +      +
    129B  THR*     3.6    31.0    -      -       -      +
    132B  LEU*     4.3    14.8    -      -       +      -
    150B  ASN*     3.0    33.3    +      -       +      +
    151B  LEU*     3.6     9.0    -      -       +      +
    153B  LYS*     1.3    76.3    -      -       +      +
    155B  SER*     1.3    55.7    +      -       -      +
    157B  ILE*     2.9    23.1    +      -       +      +
    158B  PHE*     2.6    46.2    +      -       +      -
----------------------------------------------------------
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Residues in contact with SER 155 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77B  LEU*     6.1     0.7    -      -       -      +
     82B  PRO*     3.9    25.1    +      -       -      -
     84B  ILE*     4.1    23.0    -      -       -      +
     87B  LEU*     3.5    11.7    -      -       -      +
    151B  LEU*     2.8    25.6    +      -       -      +
    152B  THR*     3.3    12.2    -      -       -      -
    154B  LEU*     1.3    75.2    -      -       -      +
    156B  LEU*     1.3    63.5    +      -       -      +
    158B  PHE*     3.2    10.3    +      -       -      -
    159B  SER*     3.0    18.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 156 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82B  PRO*     3.9    12.5    -      -       +      +
    152B  THR      3.0    11.5    +      -       -      +
    153B  LYS*     3.2     9.6    -      -       -      +
    154B  LEU      3.1     0.2    -      -       -      -
    155B  SER*     1.3    76.9    -      -       -      +
    157B  ILE*     1.3    61.1    +      -       -      +
    159B  SER*     3.1     5.0    +      -       -      -
    160B  HIS*     3.0    52.5    +      -       +      +
    271B  PHE*     3.4    50.9    -      -       +      +
    272B  LEU      3.8    13.5    -      -       -      +
    273B  THR*     4.3     7.6    -      -       +      -
    295B  LEU      6.0     1.3    -      -       -      +
    297B  CYS*     4.0    27.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 157 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125B  LYS*     4.0     9.9    -      -       +      -
    153B  LYS*     2.8    35.1    +      -       +      +
    154B  LEU*     2.9    26.7    +      -       +      +
    156B  LEU*     1.3    73.4    -      -       -      +
    158B  PHE*     1.3    65.2    +      -       -      +
    160B  HIS*     3.2     2.5    +      -       -      +
    161B  MET*     2.9    43.5    +      -       +      +
    230B  LEU      3.8    18.6    -      -       -      +
    231B  THR*     3.8    21.3    -      -       -      +
    232B  CYS*     3.4    26.5    -      -       +      -
    271B  PHE*     4.1    11.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 158 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66B  VAL*     5.2     1.3    -      -       +      -
     84B  ILE*     3.4    27.8    -      -       +      -
     87B  LEU*     4.3    18.0    -      -       +      +
     88B  LEU*     3.8    25.4    -      -       +      -
     91B  THR*     4.9     5.6    +      -       +      +
    122B  LEU*     4.2     9.2    -      -       +      -
    125B  LYS*     4.0    20.0    -      -       +      -
    126B  THR*     3.9    21.5    -      -       +      -
    129B  THR*     3.6    27.1    -      -       +      -
    154B  LEU*     2.6    36.5    +      -       +      -
    155B  SER*     3.5     6.3    -      -       -      +
    157B  ILE*     1.3    72.7    -      -       -      +
    159B  SER*     1.3    58.3    +      -       -      +
    161B  MET*     3.1    27.8    -      -       +      +
    162B  LEU*     3.0    30.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 159 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82B  PRO*     4.0     2.1    -      -       -      +
     87B  LEU*     3.8    26.4    -      -       -      +
    155B  SER      3.0    12.7    +      -       -      -
    156B  LEU      3.1     9.6    +      -       -      -
    158B  PHE*     1.3    77.7    -      -       -      +
    160B  HIS*     1.3    58.8    +      -       -      +
    162B  LEU*     3.4     2.9    +      -       -      +
    163B  ALA*     3.0    28.6    +      -       -      +
    297B  CYS*     3.4    35.8    +      -       -      -
    300B  LEU*     5.5     0.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 160 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    156B  LEU*     3.0    45.9    +      -       +      +
    157B  ILE      3.8     4.5    -      -       -      +
    159B  SER*     1.3    75.0    +      -       -      +
    161B  MET*     1.3    61.6    +      -       -      +
    163B  ALA*     3.4     1.6    +      -       -      +
    164B  GLU*     2.9    29.6    +      -       -      +
    230B  LEU*     3.7    53.0    -      -       +      +
    231B  THR*     4.3     3.2    -      -       +      +
    239B  PHE*     4.5     3.3    -      -       +      -
    271B  PHE*     4.2    12.0    -      +       -      -
    295B  LEU*     5.2     8.5    -      -       +      +
    296B  SER      5.0     0.4    -      -       -      -
    297B  CYS*     4.9     8.7    +      -       +      -
    300B  LEU*     3.5    38.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 161 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    118B  PHE*     3.4    27.7    -      -       +      +
    121B  ASN*     3.4    23.3    -      -       -      +
    122B  LEU*     4.8    12.6    -      -       -      -
    125B  LYS*     4.0    12.8    -      -       +      -
    157B  ILE*     2.9    28.0    +      -       +      +
    158B  PHE*     3.1    58.3    -      -       +      +
    160B  HIS*     1.3    77.3    -      -       -      +
    162B  LEU*     1.3    56.8    +      -       -      +
    164B  GLU*     3.2     2.1    +      -       -      +
    165B  LEU      2.8    26.0    +      -       -      -
    231B  THR*     3.8    29.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 162 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87B  LEU*     4.0    19.5    -      -       +      -
     90B  ASP*     3.7    31.6    -      -       +      +
     91B  THR*     3.8    32.3    +      -       -      +
     94B  HIS*     4.5     7.6    -      -       +      -
    118B  PHE*     5.0     2.2    -      -       -      -
    158B  PHE      3.0    17.4    +      -       -      +
    159B  SER      3.8     4.5    -      -       -      +
    161B  MET*     1.3    77.3    -      -       -      +
    163B  ALA*     1.3    63.9    +      -       -      +
    165B  LEU*     3.3     9.3    +      -       +      +
    166B  LYS*     3.0    53.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 163 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    159B  SER      3.0    15.0    +      -       -      +
    160B  HIS      3.6     1.3    -      -       -      +
    162B  LEU*     1.3    76.9    -      -       -      +
    164B  GLU*     1.3    57.2    +      -       -      +
    166B  LYS*     3.2     8.8    +      -       -      +
    167B  GLY*     2.9    25.8    +      -       -      -
    239B  PHE*     3.7     9.2    -      -       +      -
    297B  CYS      6.0     0.2    -      -       -      +
    300B  LEU*     3.4    33.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 164 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114B  TYR*     2.7    32.5    +      -       +      +
    118B  PHE*     3.9     9.9    -      -       -      +
    160B  HIS      2.9    18.2    +      -       -      +
    161B  MET*     3.5     2.9    -      -       -      +
    163B  ALA*     1.3    76.7    -      -       -      +
    165B  LEU*     1.3    62.9    +      -       -      +
    167B  GLY*     3.0     1.9    +      -       -      -
    168B  ILE*     2.9    28.9    +      -       +      +
    199B  ILE*     5.7     0.7    -      -       -      +
    231B  THR*     3.6    20.2    +      -       +      +
    233B  ASN*     5.4     3.9    +      -       -      -
    237B  SER*     2.5    32.5    +      -       -      +
    239B  PHE*     3.6    28.1    -      -       +      -
    240B  GLU*     3.6    15.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 165 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91B  THR*     4.8     3.6    -      -       +      -
     94B  HIS*     3.8    29.2    -      -       +      +
     95B  LEU*     4.2    17.3    -      -       +      +
     98B  ILE*     5.2     2.5    -      -       +      -
    114B  TYR*     3.6    10.7    +      -       +      -
    115B  PHE*     4.8    10.1    -      -       +      -
    118B  PHE*     3.6    42.8    -      -       +      -
    161B  MET      2.8    20.4    +      -       -      +
    162B  LEU*     3.6    12.3    -      -       +      +
    164B  GLU*     1.3    73.4    -      -       -      +
    166B  LYS*     1.3    58.3    +      -       -      +
    168B  ILE*     4.0     0.2    -      -       -      -
    169B  PHE*     2.8    57.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 166 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     90B  ASP*     5.2     9.4    +      -       -      +
     94B  HIS*     3.8    39.5    -      -       +      +
    162B  LEU*     3.0    46.6    +      -       +      +
    163B  ALA*     3.7     6.3    -      -       -      +
    165B  LEU*     1.3    76.4    -      -       -      +
    167B  GLY*     1.3    58.4    +      -       -      +
    170B  PRO*     3.2    31.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 167 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    163B  ALA      2.9    14.3    +      -       -      -
    164B  GLU      3.0     4.4    +      -       -      -
    166B  LYS*     1.3    79.0    -      -       -      +
    168B  ILE*     1.3    61.6    +      -       -      +
    170B  PRO*     3.7    10.4    -      -       -      +
    175B  GLN*     5.4     1.7    -      -       -      +
    179B  PHE*     3.7    21.0    -      -       -      -
    239B  PHE*     4.2    15.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 168 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114B  TYR*     3.7    39.5    -      -       +      -
    164B  GLU*     2.9    22.4    +      -       +      +
    165B  LEU      4.1     0.2    -      -       -      +
    167B  GLY*     1.3    77.3    -      -       -      +
    169B  PHE*     1.3    56.5    +      -       +      +
    170B  PRO*     3.2     9.4    -      -       -      +
    174B  PHE*     3.4    33.6    -      -       +      -
    175B  GLN*     2.8    33.8    +      -       -      -
    176B  GLY*     3.8     8.5    -      -       -      +
    179B  PHE*     4.0    10.8    -      -       +      -
    198B  THR*     3.7    17.5    -      -       +      -
    237B  SER*     5.5     0.7    -      -       -      -
    238B  VAL*     4.0    18.2    -      -       +      -
    239B  PHE*     4.2     9.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 169 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     94B  HIS*     2.9    21.2    -      -       +      -
     98B  ILE*     3.6    22.2    -      -       +      -
    102B  TYR*     4.1     5.8    -      +       -      -
    109B  LEU*     4.0    19.1    -      -       +      -
    112B  ASN*     4.3     3.1    -      -       -      -
    114B  TYR*     3.6    26.5    -      +       -      -
    115B  PHE*     4.0    29.6    -      +       +      -
    165B  LEU*     2.8    28.8    +      -       +      +
    166B  LYS      3.5     3.4    -      -       -      -
    168B  ILE*     1.3    81.7    -      -       +      +
    170B  PRO*     1.3    65.8    -      -       -      +
    172B  GLY      3.1    18.1    +      -       -      -
    173B  LEU      3.5     2.9    -      -       -      -
    174B  PHE*     3.4    47.3    -      +       +      -
----------------------------------------------------------
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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