Contacts of the helix formed by residues 137 - 163 (chain B) in PDB entry 2ITB


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 137 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27B  GLN*     4.7     5.5    +      -       -      +
     83B  ARG*     2.8    44.3    +      -       -      -
    136B  LEU*     1.3    74.8    -      -       -      +
    138B  GLU*     1.3    67.7    +      -       -      +
    139B  GLU*     3.4     5.2    +      -       -      +
    140B  LEU*     3.0    18.0    +      -       -      +
    141B  GLY*     2.9    20.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 138 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    136B  LEU      3.7     1.5    +      -       -      -
    137B  ASP*     1.3    72.5    -      -       -      +
    139B  GLU*     1.3    67.2    +      -       -      +
    141B  GLY*     3.8     1.0    -      -       -      -
    142B  ARG*     2.9    62.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 139 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     79B  LEU*     3.9     6.9    -      -       +      +
     82B  ARG*     3.1    35.9    +      -       -      +
     83B  ARG*     3.1    28.5    +      -       -      +
    137B  ASP*     3.4     2.9    +      -       -      +
    138B  GLU*     1.3    82.0    -      -       -      +
    140B  LEU*     1.3    63.6    +      -       -      +
    142B  ARG*     3.8     4.9    -      -       -      +
    143B  PHE*     3.0    22.8    +      -       +      +
    512B  EDO      4.7     6.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 140 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27B  GLN*     3.8    23.8    -      -       +      +
     30B  LEU*     6.0     2.7    -      -       +      -
     31B  LEU*     4.2    14.6    -      -       +      -
     79B  LEU*     3.7    26.9    -      -       +      -
     83B  ARG*     3.7    17.7    -      -       -      +
    136B  LEU*     4.0    22.2    -      -       +      -
    137B  ASP*     3.0    23.0    +      -       -      +
    139B  GLU*     1.3    77.1    -      -       -      +
    141B  GLY*     1.3    57.0    +      -       -      +
    143B  PHE*     3.2    11.8    +      -       +      +
    144B  TYR*     2.9    53.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 141 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    133B  VAL*     3.5    29.0    -      -       -      +
    136B  LEU*     4.0    18.1    -      -       -      +
    137B  ASP      2.9    15.9    +      -       -      -
    138B  GLU*     3.8     0.9    -      -       -      -
    140B  LEU*     1.3    77.1    -      -       -      +
    142B  ARG*     1.3    55.8    +      -       -      +
    144B  TYR*     3.4     1.0    +      -       -      -
    145B  HIS*     2.9    25.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 142 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    138B  GLU*     2.9    56.3    +      -       -      +
    139B  GLU*     3.8     4.5    -      -       -      +
    141B  GLY*     1.3    72.4    -      -       -      +
    143B  PHE*     1.3    65.9    +      -       -      +
    145B  HIS*     3.7     9.8    -      -       +      +
    146B  GLY*     3.1    19.4    +      -       -      -
    511B  EDO      4.6     0.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 143 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31B  LEU*     5.9     0.4    -      -       +      -
     72B  HIS      4.7     0.2    -      -       -      -
     75B  GLN*     3.7    50.0    -      -       +      -
     76B  VAL*     4.0    24.5    -      -       +      -
     79B  LEU*     5.0    13.9    -      -       +      -
    139B  GLU*     3.0    15.4    +      -       +      +
    140B  LEU*     3.4    17.7    -      -       +      +
    142B  ARG*     1.3    76.8    -      -       -      +
    144B  TYR*     1.3    93.7    +      +       -      +
    146B  GLY      3.1     9.9    +      -       -      -
    147B  LEU*     3.2    27.6    +      -       +      +
    511B  EDO      3.2    23.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 144 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30B  LEU*     4.6    14.4    -      -       +      +
     31B  LEU*     3.8    14.7    -      -       +      +
     34B  HIS*     2.9    42.2    +      +       -      +
    129B  PHE*     3.6    27.9    -      +       +      +
    132B  LEU*     4.2    20.4    -      -       +      -
    133B  VAL*     4.0    12.1    -      -       +      -
    136B  LEU*     3.5    25.4    -      -       +      -
    140B  LEU*     2.9    30.1    +      -       +      +
    141B  GLY      3.8     4.9    -      -       -      +
    142B  ARG      3.3     0.2    -      -       -      -
    143B  PHE*     1.3    94.5    -      +       -      +
    145B  HIS*     1.3    64.6    +      -       -      +
    147B  LEU*     3.2    20.4    +      -       +      +
    148B  LEU*     3.4    12.6    +      -       -      +
    195B  PHE*     4.5     3.7    -      +       -      -
----------------------------------------------------------
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Residues in contact with HIS 145 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    133B  VAL*     3.7    17.9    -      -       +      +
    141B  GLY      2.9    17.9    +      -       -      +
    142B  ARG*     3.7     9.6    -      -       +      +
    143B  PHE      3.3     0.2    -      -       -      -
    144B  TYR*     1.3    74.9    -      -       -      +
    146B  GLY*     1.3    62.4    +      -       -      +
    148B  LEU*     3.1    47.1    +      -       +      +
    149B  LYS*     4.1     2.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 146 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    142B  ARG      3.1    13.8    +      -       -      -
    143B  PHE      3.1     0.6    +      -       -      -
    145B  HIS*     1.3    80.2    -      -       -      +
    147B  LEU*     1.3    57.5    -      -       -      +
    148B  LEU      3.6     0.2    +      -       -      -
    149B  LYS*     4.0    10.2    +      -       -      +
    150B  SER*     3.7    11.8    +      -       -      -
    511B  EDO      3.4    25.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 147 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34B  HIS*     3.5    32.1    -      -       +      +
     38B  GLU*     4.5     1.6    -      -       -      +
     72B  HIS*     3.4    48.2    -      -       +      +
     75B  GLN*     4.3     2.9    -      -       -      +
    129B  PHE*     3.7    25.1    -      -       +      -
    143B  PHE*     3.2    29.2    +      -       +      +
    144B  TYR*     3.2    12.7    +      -       +      +
    146B  GLY*     1.3    76.5    -      -       -      +
    148B  LEU*     1.3    63.5    +      -       -      +
    150B  SER*     3.2     6.9    +      -       -      -
    151B  GLU*     3.0    26.5    +      -       +      +
    511B  EDO      3.7    10.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 148 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126B  CYS*     2.9    49.9    -      -       -      +
    129B  PHE*     3.3    23.3    -      -       +      -
    130B  ALA*     3.5    23.3    -      -       +      +
    133B  VAL*     5.3     0.7    -      -       +      -
    144B  TYR      3.4     6.1    +      -       -      +
    145B  HIS*     3.1    41.5    +      -       +      +
    147B  LEU*     1.3    76.2    -      -       -      +
    149B  LYS*     1.3    63.9    +      -       -      +
    151B  GLU*     3.2     4.5    +      -       -      -
    152B  ALA*     3.0    20.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 149 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    145B  HIS      4.1     1.5    +      -       -      +
    146B  GLY*     4.0     9.4    +      -       -      +
    147B  LEU      3.4     0.4    -      -       -      -
    148B  LEU*     1.3    78.3    -      -       -      +
    150B  SER*     1.3    62.8    +      -       -      +
    152B  ALA*     3.4     8.4    +      -       -      +
    153B  ARG*     3.2    26.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 150 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68B  GLU*     4.4    10.7    +      -       -      -
     72B  HIS*     3.9    30.5    +      -       -      -
    146B  GLY      3.7    12.1    +      -       -      -
    147B  LEU*     3.2     9.2    +      -       -      -
    149B  LYS*     1.3    77.2    -      -       -      +
    151B  GLU*     1.3    66.5    +      -       -      +
    153B  ARG*     3.0    13.2    +      -       -      +
    154B  HIS*     3.0    27.8    +      -       -      -
    511B  EDO      4.5     5.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 151 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72B  HIS*     4.3     3.9    -      -       -      -
    122B  GLU*     3.3    30.5    -      -       -      +
    125B  SER*     3.6    13.8    -      -       -      -
    126B  CYS*     3.7    19.3    -      -       +      +
    129B  PHE*     3.6    25.6    -      -       +      -
    147B  LEU*     3.0    20.7    +      -       -      +
    148B  LEU      3.2     1.7    +      -       -      +
    150B  SER*     1.3    76.7    -      -       -      +
    152B  ALA*     1.3    58.2    +      -       -      +
    154B  HIS*     3.2     5.5    +      -       -      +
    155B  TYR*     2.9    30.0    +      -       -      +
    501B   FE      3.2     8.9    -      -       -      -
    502B   FE      2.6    20.1    -      -       -      -
    503B  UNL      2.7    20.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 152 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7B  ILE*     3.9    25.6    -      -       +      -
    126B  CYS*     4.4     3.3    -      -       -      -
    148B  LEU      3.0    15.9    +      -       -      +
    149B  LYS*     3.6     9.9    -      -       -      +
    151B  GLU*     1.3    78.8    -      -       -      +
    153B  ARG*     1.3    56.9    +      -       +      +
    155B  TYR*     3.5     4.0    +      -       +      -
    156B  GLN*     3.1    41.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 153 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68B  GLU*     4.8    15.0    +      -       -      -
    149B  LYS      3.2    15.0    +      -       -      +
    150B  SER*     3.0    12.6    +      -       -      +
    152B  ALA*     1.3    75.3    -      -       +      +
    154B  HIS*     1.3    63.2    +      -       +      +
    156B  GLN*     3.4    15.3    +      -       -      +
    157B  GLY*     3.0    24.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 154 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61B  MSE      6.2     0.2    -      -       -      -
     65B  LEU*     3.8    26.8    -      -       +      +
     68B  GLU*     3.2    45.1    +      -       +      +
     69B  GLU*     3.4    18.1    +      -       -      -
     72B  HIS*     4.1     6.5    -      +       -      -
    122B  GLU*     3.3    21.1    -      -       +      +
    150B  SER      3.0    16.4    +      -       -      -
    151B  GLU*     3.2     9.7    +      -       -      +
    153B  ARG*     1.3    79.2    -      -       +      +
    155B  TYR*     1.3    67.6    +      -       -      +
    157B  GLY*     3.2     2.0    +      -       -      -
    158B  TYR*     2.9    31.7    +      -       -      -
    502B   FE      2.4    28.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 155 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      4B  ILE*     4.8     2.9    -      -       +      -
      5B  PRO*     2.3    54.4    +      -       -      +
      7B  ILE*     3.8    20.9    -      -       +      -
     10B  PHE*     3.4    39.4    -      +       +      +
    119B  ALA*     3.6    27.6    -      -       +      +
    122B  GLU*     3.7    11.7    -      -       +      +
    123B  ALA*     3.9     9.2    -      -       +      +
    151B  GLU      2.9    17.2    +      -       -      +
    152B  ALA*     3.6    11.4    -      -       +      +
    154B  HIS*     1.3    77.7    -      -       -      +
    156B  GLN*     1.3    82.8    +      -       +      +
    158B  TYR*     3.5     2.9    +      -       -      +
    159B  LEU*     3.2    34.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 156 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      4B  ILE*     4.4    15.7    -      -       +      +
    152B  ALA*     3.1    31.2    +      -       -      +
    153B  ARG*     3.7    14.1    -      -       -      +
    155B  TYR*     1.3    94.2    -      -       +      +
    157B  GLY*     1.3    57.3    +      -       -      +
    159B  LEU*     3.5     4.0    +      -       -      +
    160B  LYS*     2.9    38.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 157 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61B  MSE      3.5    22.3    -      -       -      +
    153B  ARG      3.0    14.5    +      -       -      -
    154B  HIS*     3.2     3.3    +      -       -      -
    156B  GLN*     1.3    75.1    -      -       -      +
    158B  TYR*     1.3    65.6    +      -       -      +
    160B  LYS*     3.8     6.4    -      -       -      +
    161B  LEU*     2.9    26.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 158 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41B  ALA      5.4     0.5    +      -       -      -
     44B  THR*     5.1     2.4    -      -       -      +
     45B  ALA*     5.4     1.7    -      -       -      +
     48B  LEU*     4.7     8.6    -      -       +      +
     61B  MSE      4.1     2.8    -      -       +      -
     62B  MSE      3.5    32.7    -      -       +      -
     65B  LEU*     3.9    19.6    -      -       +      +
    114B  THR      5.1     0.9    -      -       -      -
    115B  LEU*     3.5    44.1    -      -       +      +
    118B  GLY*     3.6    20.2    -      -       -      -
    119B  ALA*     3.6     9.6    -      -       -      +
    122B  GLU*     3.8     8.7    -      -       +      -
    154B  HIS      2.9    23.7    +      -       -      +
    155B  TYR      3.7     3.8    -      -       -      +
    157B  GLY*     1.3    75.8    -      -       -      +
    159B  LEU*     1.3    57.6    +      -       -      +
    161B  LEU*     3.3     5.6    +      -       -      +
    162B  ALA*     2.9    27.5    +      -       -      +
    510B  EDO      3.2    43.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 159 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      4B  ILE*     4.5    10.8    -      -       +      -
      5B  PRO*     4.1    13.5    -      -       +      -
     10B  PHE*     3.8    34.5    -      -       +      -
    115B  LEU      5.4     0.2    -      -       -      -
    116B  VAL*     4.7     5.2    -      -       +      -
    119B  ALA*     4.3     7.2    -      -       +      -
    155B  TYR*     3.2    35.4    +      -       +      +
    156B  GLN*     3.9     3.6    -      -       -      +
    158B  TYR*     1.3    76.6    -      -       -      +
    160B  LYS*     1.3    65.2    +      -       -      +
    162B  ALA*     3.1    15.0    +      -       +      +
    163B  HIS*     3.0    31.1    +      -       +      -
    171B  ILE*     4.4    13.0    -      -       +      -
    175B  VAL*     4.3    15.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 160 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      4B  ILE*     5.8     5.8    -      -       +      -
    156B  GLN*     2.9    29.6    +      -       +      +
    157B  GLY*     3.8     6.1    -      -       -      +
    159B  LEU*     1.3    75.0    -      -       -      +
    161B  LEU*     1.3    63.5    +      -       -      +
    163B  HIS*     3.2    23.2    +      -       -      +
    164B  ASN*     3.9     7.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 161 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57B  ASP*     4.2     8.7    -      -       +      +
     58B  LEU*     4.0    38.8    -      -       +      +
     61B  MSE      3.7    24.9    -      -       +      -
     62B  MSE      3.9    22.2    -      -       +      -
    115B  LEU*     3.9    16.6    -      -       +      -
    157B  GLY      2.9    15.3    +      -       -      +
    158B  TYR*     3.5     4.9    -      -       -      +
    160B  LYS*     1.3    79.5    -      -       -      +
    162B  ALA*     1.3    61.7    +      -       -      +
    164B  ASN*     3.1    34.8    +      -       -      +
    165B  TYR*     3.3    21.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 162 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112B  VAL*     4.5     3.9    -      -       -      +
    115B  LEU*     3.8    23.7    -      -       +      +
    116B  VAL*     4.3    16.4    -      -       +      +
    158B  TYR      2.9    14.2    +      -       -      +
    159B  LEU*     3.1    14.3    +      -       +      +
    161B  LEU*     1.3    76.3    -      -       -      +
    163B  HIS*     1.3    56.8    +      -       -      +
    164B  ASN      3.1     0.2    -      -       -      -
    165B  TYR*     3.1    19.4    +      -       -      +
    166B  GLY      3.6     1.4    +      -       -      -
    171B  ILE*     3.2    33.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 163 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      4B  ILE*     6.3     1.6    -      -       -      -
    159B  LEU*     3.0    34.5    +      -       +      -
    160B  LYS*     3.2    12.0    +      -       -      +
    161B  LEU      3.1     1.8    -      -       -      -
    162B  ALA*     1.3    74.6    -      -       -      +
    164B  ASN*     1.3    62.8    +      -       -      +
    165B  TYR      3.2     1.0    +      -       -      -
    166B  GLY      3.7     9.6    -      -       -      +
    168B  GLU*     4.2    29.5    +      -       +      +
    171B  ILE*     3.7    37.1    -      -       +      +
    172B  ALA      5.6     0.2    +      -       -      -
    507B  EDO      3.5    15.9    +      -       -      -
----------------------------------------------------------
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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