Contacts of the helix formed by residues 154 - 179 (chain B) in PDB entry 2Y01


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 154 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75B  LEU*     3.8     7.0    -      -       -      +
    150B  GLN      5.3     0.4    -      -       -      +
    151B  SER      3.8    13.7    -      -       -      +
    152B  LEU      3.2    11.8    +      -       -      +
    153B  MET*     1.3    79.5    -      -       -      +
    155B  ARG*     1.3    64.8    +      -       -      +
    156B  ALA*     3.4     9.0    +      -       -      +
    157B  ARG*     3.1    33.2    +      -       -      +
    158B  ALA*     3.0    23.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 155 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73B  GLN*     3.4    44.1    +      -       -      +
     74B  THR      4.1     9.1    +      -       -      -
     75B  LEU*     3.7    22.2    -      -       +      +
     78B  LEU*     4.1    27.3    -      -       +      +
    154B  THR*     1.3    75.1    -      -       -      +
    156B  ALA*     1.3    62.6    +      -       -      +
    158B  ALA*     3.4     3.4    +      -       -      +
    159B  LYS*     3.1    28.8    +      -       +      +
    402B  Y01      3.8    24.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 156 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    501A  2CV      6.1     1.6    -      -       -      +
    154B  THR*     3.2     8.4    +      -       -      +
    155B  ARG*     1.3    78.7    -      -       -      +
    157B  ARG*     1.3    62.7    +      -       +      +
    159B  LYS*     3.4    11.8    +      -       -      +
    160B  VAL*     3.2    26.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 157 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    205A  ARG*     5.8     0.4    -      -       -      +
    501A  2CV      6.0     0.2    -      -       -      +
    503A  2CV      3.6    64.6    +      -       +      +
    151B  SER      4.2     2.2    +      -       -      -
    152B  LEU*     2.9    37.8    +      -       -      +
    153B  MET*     5.0     5.4    -      -       -      -
    154B  THR*     3.1    31.5    +      -       -      +
    156B  ALA*     1.3    75.8    -      -       +      +
    158B  ALA*     1.3    59.8    +      -       -      +
    160B  VAL*     2.9    10.3    +      -       -      +
    161B  ILE*     2.8    36.3    +      -       +      +
    401B  Y01      3.2    38.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 158 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75B  LEU*     4.3     9.2    -      -       +      +
     78B  LEU*     4.0    22.9    -      -       +      -
     79B  PHE*     4.1    17.4    -      -       +      -
    153B  MET*     4.6     6.1    -      -       -      -
    154B  THR      3.0    17.0    +      -       -      +
    155B  ARG      3.6     4.9    -      -       -      +
    157B  ARG*     1.3    74.6    -      -       -      +
    159B  LYS*     1.3    62.5    +      -       -      +
    161B  ILE*     3.2    14.2    +      -       -      +
    162B  ILE*     3.0    29.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 159 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78B  LEU*     5.4     2.2    -      -       +      +
    155B  ARG*     3.1    16.9    +      -       +      +
    156B  ALA*     3.5    14.4    -      -       -      +
    157B  ARG      3.2     0.2    -      -       -      -
    158B  ALA*     1.3    74.0    -      -       -      +
    160B  VAL*     1.3    58.9    +      -       +      +
    162B  ILE*     3.5     7.0    +      -       -      +
    163B  CYS*     3.0    34.6    +      -       -      -
    402B  Y01      3.5    57.0    +      -       +      +
    505B  2CV      3.8    24.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 160 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    206A  ALA*     3.7    15.7    -      -       +      -
    501A  2CV      3.4    47.6    -      -       -      +
    156B  ALA      3.2    14.8    +      -       -      +
    157B  ARG*     2.9     9.4    +      -       -      +
    159B  LYS*     1.3    73.6    -      -       -      +
    161B  ILE*     1.3    60.5    +      -       -      +
    163B  CYS*     3.4     1.8    +      -       -      +
    164B  THR*     2.8    35.2    +      -       -      +
    401B  Y01      3.6    28.7    -      -       +      +
    505B  2CV      3.5    18.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 161 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    503A  2CV      4.5    15.9    -      -       +      -
     79B  PHE*     4.0     9.6    -      -       +      -
    134B  VAL*     3.6    39.0    -      -       +      -
    153B  MET*     3.6    35.9    -      -       +      -
    157B  ARG*     2.8    19.9    +      -       +      +
    158B  ALA*     3.5     6.3    -      -       -      +
    160B  VAL*     1.3    76.0    -      -       -      +
    162B  ILE*     1.3    63.3    +      -       -      +
    164B  THR*     3.2     4.0    +      -       -      -
    165B  VAL*     2.9    23.6    +      -       +      +
    401B  Y01      3.8    37.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 162 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78B  LEU*     3.4    38.1    -      -       +      +
     79B  PHE*     3.7    19.7    -      -       +      -
     82B  SER*     3.4    25.8    -      -       -      +
    131B  THR*     6.0     0.7    -      -       +      -
    158B  ALA      3.0    21.7    +      -       -      +
    159B  LYS      3.9     3.6    -      -       -      +
    161B  ILE*     1.3    76.6    -      -       -      +
    163B  CYS*     1.3    58.7    +      -       -      +
    165B  VAL*     3.3     6.5    +      -       -      +
    166B  TRP*     3.0    41.5    +      -       +      -
    402B  Y01      3.7    44.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 163 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    501A  2CV      5.4     0.4    -      -       +      -
    159B  LYS*     3.0    22.2    +      -       -      +
    160B  VAL      3.9     2.5    -      -       -      +
    162B  ILE*     1.3    77.9    -      -       -      +
    164B  THR*     1.3    55.6    +      -       -      +
    166B  TRP*     3.3     5.3    +      -       -      -
    167B  ALA*     2.9    29.0    +      -       -      +
    402B  Y01      3.8    32.5    -      -       -      -
    505B  2CV      3.6    56.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 164 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    206A  ALA*     3.5    20.5    -      -       +      +
    210A  ALA*     4.3     5.4    -      -       +      -
    501A  2CV      3.6    24.9    -      -       +      +
    160B  VAL*     2.8    23.5    +      -       -      +
    161B  ILE      3.6     3.8    -      -       -      -
    163B  CYS*     1.3    74.2    -      -       -      +
    165B  VAL*     1.3    59.6    +      -       -      +
    167B  ALA*     3.0     7.2    +      -       -      +
    168B  ILE*     2.8    53.9    +      -       +      +
    401B  Y01      3.8    29.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 165 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82B  SER*     5.7     0.4    -      -       -      +
    127B  ALA*     4.0     6.5    -      -       -      +
    130B  GLU*     3.6    30.0    -      -       +      +
    131B  THR*     3.7    23.8    -      -       -      +
    134B  VAL*     3.9    27.6    -      -       +      -
    161B  ILE*     2.9    17.4    +      -       +      +
    162B  ILE*     3.5    11.2    -      -       -      +
    164B  THR*     1.3    74.9    -      -       -      +
    166B  TRP*     1.3    68.0    +      -       +      +
    168B  ILE*     3.6     2.4    +      -       -      -
    169B  SER*     2.9    31.6    +      -       -      +
    401B  Y01      4.1    15.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 166 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82B  SER*     3.0    37.4    +      -       -      -
     85B  CYS      4.7     1.1    -      -       -      -
     86B  ALA*     3.8    27.4    -      -       +      -
     89B  VAL*     5.2     3.6    -      -       +      -
    123B  LEU*     3.8    36.0    -      -       +      +
    124B  CYS*     5.1     5.2    -      -       -      -
    127B  ALA*     3.9    25.2    -      -       +      +
    131B  THR*     5.0     2.3    +      -       -      -
    162B  ILE*     3.0    31.3    +      -       +      +
    163B  CYS*     3.9     4.3    -      -       -      +
    164B  THR      3.3     0.2    -      -       -      -
    165B  VAL*     1.3    80.2    -      -       +      +
    167B  ALA*     1.3    56.7    +      -       -      +
    169B  SER*     3.5     3.1    +      -       -      -
    170B  ALA*     2.9    30.7    +      -       -      +
    402B  Y01      3.4    59.1    -      -       +      +
    505B  2CV      3.6    25.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 167 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181A  TRP*     3.4    30.3    -      -       +      -
    501A  2CV      4.1    22.9    -      -       +      -
    163B  CYS      2.9    14.9    +      -       -      +
    164B  THR*     3.0    10.5    +      -       -      +
    166B  TRP*     1.3    73.8    -      -       -      +
    168B  ILE*     1.3    65.4    +      -       -      +
    170B  ALA*     3.4     1.8    +      -       -      +
    171B  LEU*     3.0    18.9    +      -       -      +
    505B  2CV      4.0    20.4    -      -       +      +
----------------------------------------------------------
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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
----------------------------------------------------------
    181A  TRP*     5.4     0.2    -      -       -      -
    210A  ALA*     4.4     6.3    -      -       +      -
    214A  ILE*     3.9    24.7    -      -       +      -
    501A  2CV      4.5    13.9    -      -       +      -
    130B  GLU*     3.8    15.5    -      -       -      +
    164B  THR*     2.8    42.7    +      -       +      +
    167B  ALA*     1.3    72.0    -      -       -      +
    169B  SER*     1.3    58.6    +      -       -      +
    171B  LEU*     3.3    12.8    +      -       +      +
    172B  VAL*     3.0    31.7    +      -       +      +
    401B  Y01      3.7    54.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 169 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    123B  LEU*     3.7    15.4    -      -       -      +
    126B  THR*     3.5    17.5    -      -       -      +
    127B  ALA*     3.4    30.2    +      -       -      -
    130B  GLU*     3.5    13.6    +      -       -      -
    165B  VAL      2.9    18.3    +      -       -      -
    166B  TRP      3.7     4.3    -      -       -      -
    168B  ILE*     1.3    75.6    -      -       -      +
    170B  ALA*     1.3    54.9    +      -       -      +
    172B  VAL*     3.5     2.4    +      -       -      +
    173B  SER*     2.8    37.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 170 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181A  TRP*     5.1     5.6    -      -       +      -
    123B  LEU*     3.6     4.9    -      -       -      +
    166B  TRP      2.9    18.1    +      -       -      +
    167B  ALA*     3.6     5.6    -      -       -      +
    169B  SER*     1.3    72.3    -      -       -      +
    171B  LEU*     1.3    66.2    +      -       -      +
    173B  SER*     3.6     5.8    -      -       -      -
    174B  PHE*     3.0    39.1    +      -       +      +
    175B  LEU      4.3     0.2    +      -       -      -
    505B  2CV      3.8    26.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 171 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    171A  LEU*     3.5    45.9    -      -       +      +
    172A  VAL*     4.5    13.5    -      -       +      -
    175A  LEU*     3.4    42.0    -      -       +      -
    176A  PRO*     4.0    21.5    -      -       +      -
    181A  TRP*     4.2    14.1    -      -       +      -
    501A  2CV      4.6    12.8    -      -       +      -
    167B  ALA      3.0    12.9    +      -       -      +
    168B  ILE*     3.4    14.1    -      -       +      +
    170B  ALA*     1.3    79.7    -      -       -      +
    172B  VAL*     1.3    64.5    +      -       +      +
    173B  SER      3.4     0.2    +      -       -      -
    175B  LEU*     3.9     3.9    -      -       +      +
    176B  PRO*     3.8     6.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 172 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    171A  LEU*     4.5    12.6    -      -       +      -
    172A  VAL*     5.7     7.4    -      -       +      -
    122B  VAL*     4.9     2.1    -      -       -      +
    126B  THR*     4.2    15.9    -      -       +      +
    168B  ILE*     3.0    20.3    +      -       +      +
    169B  SER*     4.1     2.0    -      -       -      +
    171B  LEU*     1.3    81.9    -      -       +      +
    173B  SER*     1.3    58.7    +      -       -      +
    176B  PRO*     3.4    18.3    -      -       -      +
    207B  TYR*     5.3     2.3    +      -       -      -
    211B  SER*     6.0     2.3    -      -       -      -
    214B  ILE*     3.6    29.8    -      -       +      -
    215B  SER*     3.6    23.8    -      -       -      +
    401B  Y01      4.6    12.1    -      -       +      -
    501B  2CV      4.1    10.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 173 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    119B  SER*     4.0     6.0    +      -       -      -
    122B  VAL*     3.7    16.6    -      -       -      -
    123B  LEU*     3.7    32.6    -      -       -      +
    126B  THR*     5.2     0.2    -      -       -      -
    169B  SER      2.8    20.0    +      -       -      -
    170B  ALA*     3.3     8.5    +      -       -      -
    172B  VAL*     1.3    81.3    -      -       -      +
    174B  PHE*     1.3    79.6    +      -       -      +
    175B  LEU      3.7     0.2    -      -       -      -
    176B  PRO*     3.6     7.5    -      -       -      +
    177B  ILE*     3.6    23.5    -      -       -      +
    207B  TYR*     4.9     0.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 174 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    116B  LEU*     3.9    18.4    -      -       +      -
    119B  SER*     3.5    32.3    -      -       -      -
    120B  LEU*     4.2    19.3    -      -       +      -
    123B  LEU*     4.3    19.3    -      -       +      -
    170B  ALA*     3.0    31.5    +      -       +      +
    173B  SER*     1.3    85.3    +      -       -      +
    175B  LEU*     1.3    69.9    +      -       +      +
    177B  ILE*     3.1     3.8    +      -       -      +
    178B  MET*     3.0    40.7    +      -       +      +
    402B  Y01      4.7     7.6    -      -       +      -
    505B  2CV      4.7     6.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 175 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    171A  LEU*     3.3    31.6    -      -       +      -
    175A  LEU*     4.5    28.9    -      -       +      -
    170B  ALA      4.3     0.4    +      -       -      -
    171B  LEU*     3.9     5.8    +      -       +      +
    174B  PHE*     1.3    79.9    -      -       +      +
    176B  PRO*     1.4    68.6    -      -       +      +
    177B  ILE      3.0     0.2    +      -       -      -
    178B  MET*     3.7     5.1    -      -       +      -
    179B  MET*     2.8    60.2    +      -       +      +
    181B  TRP*     4.7     7.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 176 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    171A  LEU*     3.8    11.4    -      -       +      -
    171B  LEU      3.8     5.6    -      -       -      +
    172B  VAL      3.4    20.4    -      -       -      +
    173B  SER      3.6     9.2    -      -       -      +
    174B  PHE      3.5     3.4    -      -       -      -
    175B  LEU*     1.4    94.8    -      -       +      +
    177B  ILE*     1.3    55.2    +      -       -      +
    179B  MET      3.7     0.3    +      -       -      -
    180B  HIS      3.2     4.7    +      -       -      -
    181B  TRP*     3.0    54.1    +      -       +      +
    182B  TRP*     3.8     2.2    +      -       -      -
    207B  TYR*     3.8    22.2    -      -       +      -
    501B  2CV      3.7    19.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 177 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    115B  GLU*     3.9    24.3    -      -       +      +
    118B  THR*     3.7    27.8    -      -       +      -
    119B  SER*     3.6    23.6    -      -       -      +
    122B  VAL*     3.8    14.6    -      -       +      -
    173B  SER      3.6    14.4    -      -       -      +
    174B  PHE      3.1     7.8    +      -       -      +
    176B  PRO*     1.3    77.6    -      -       -      +
    178B  MET*     1.3    63.7    +      -       -      +
    180B  HIS*     3.5     8.1    +      -       -      -
    182B  TRP*     2.9    41.9    +      -       +      +
    201B  PHE*     4.5     1.3    -      -       +      -
    207B  TYR*     3.4    26.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 178 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112B  PHE*     4.7    16.8    -      -       +      -
    115B  GLU*     3.9    26.1    -      -       +      +
    116B  LEU*     4.2    28.0    -      -       +      +
    119B  SER*     3.8    19.5    -      -       -      +
    174B  PHE*     3.0    36.4    +      -       +      +
    175B  LEU*     4.1     6.7    -      -       +      +
    177B  ILE*     1.3    72.6    -      -       -      +
    179B  MET*     1.3    65.1    +      -       +      +
    180B  HIS*     3.2    11.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with MET 179 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175B  LEU*     2.8    48.8    +      -       +      +
    176B  PRO      3.9     1.1    -      -       -      +
    178B  MET*     1.3    78.5    -      -       -      +
    180B  HIS*     1.3    68.0    +      -       -      +
    181B  TRP*     3.3    44.9    +      -       +      +
----------------------------------------------------------
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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