Contacts of the helix formed by residues 166 - 192 (chain A) in PDB entry 1YV5


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 TYR 166 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95A  SER*     6.0     0.2    -      -       -      -
     98A  ARG*     3.3    31.4    +      -       -      -
    161A  CYS*     4.0    13.9    -      -       +      -
    164A  GLN*     3.5    26.2    -      -       +      -
    165A  PRO*     1.3    83.7    -      -       +      +
    167A  TYR*     1.3    67.3    +      -       -      +
    168A  LEU      3.4     2.2    -      -       -      -
    169A  ASN*     3.2    13.2    +      -       +      +
    170A  LEU*     3.0    46.3    +      -       +      +
    229A  TYR*     3.4    27.8    -      -       +      +
    230A  MET*     3.4    50.0    -      -       +      +
    234A  ASP*     5.8     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 167 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    154A  TYR      4.8     1.6    +      -       -      -
    157A  LEU*     3.6    28.9    -      -       +      -
    158A  LYS*     3.5    30.2    +      -       -      +
    161A  CYS*     3.4    33.4    -      -       +      +
    162A  ARG*     3.7    30.5    -      -       +      +
    164A  GLN      3.3    11.0    +      -       -      +
    165A  PRO      3.4     1.0    -      -       -      -
    166A  TYR*     1.3    84.9    -      -       -      +
    168A  LEU*     1.3    67.0    +      -       +      +
    170A  LEU*     3.1     4.9    +      -       +      +
    171A  ILE*     3.1    52.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 168 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    165A  PRO      5.0     2.3    +      -       -      +
    166A  TYR      3.4     0.4    -      -       -      -
    167A  TYR*     1.3    81.9    -      -       +      +
    169A  ASN*     1.3    58.3    +      -       -      +
    171A  ILE*     4.5    17.7    -      -       +      -
    172A  GLU*     3.0    60.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 169 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    165A  PRO      5.1     3.4    +      -       -      -
    166A  TYR*     3.2    19.0    +      -       -      +
    168A  LEU*     1.3    78.6    -      -       -      +
    170A  LEU*     1.3    58.9    +      -       -      +
    172A  GLU*     3.9    12.2    -      -       -      +
    173A  LEU*     2.9    28.4    +      -       -      +
    229A  TYR*     3.6    46.9    -      -       +      +
    234A  ASP*     4.1    15.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 170 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102A  VAL*     3.9    26.2    -      -       +      -
    157A  LEU*     4.2    17.3    -      -       +      -
    161A  CYS*     4.6     3.1    -      -       +      -
    166A  TYR*     3.0    44.1    +      -       +      +
    167A  TYR*     3.6     8.1    -      -       +      +
    169A  ASN*     1.3    75.2    -      -       -      +
    171A  ILE*     1.3    64.4    +      -       -      +
    173A  LEU*     3.1     8.7    +      -       +      +
    174A  PHE*     2.9    35.3    +      -       +      -
    226A  ALA*     3.7    41.5    -      -       +      +
    229A  TYR*     4.2     9.0    -      -       +      -
    230A  MET*     4.1     4.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 171 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    154A  TYR*     4.1    17.0    -      -       +      -
    157A  LEU*     4.4    17.0    -      -       +      +
    167A  TYR*     3.1    56.8    +      -       +      +
    168A  LEU*     3.9    19.3    -      -       +      +
    170A  LEU*     1.3    74.9    -      -       -      +
    172A  GLU*     1.3    59.1    +      -       +      +
    174A  PHE*     3.4     1.9    +      -       -      +
    175A  LEU*     3.0    51.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 172 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168A  LEU*     3.0    45.5    +      -       +      +
    169A  ASN*     3.9    14.9    -      -       -      +
    171A  ILE*     1.3    80.2    -      -       +      +
    173A  LEU*     1.3    56.6    +      -       -      +
    175A  LEU*     3.9    10.3    -      -       +      +
    176A  GLN*     3.0    31.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 173 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    169A  ASN      2.9    19.0    +      -       -      +
    170A  LEU*     3.1     9.4    +      -       +      +
    172A  GLU*     1.3    76.6    -      -       -      +
    174A  PHE*     1.3    57.6    +      -       +      +
    176A  GLN*     3.4     9.7    +      -       -      +
    177A  SER*     2.9    32.4    +      -       -      -
    221A  TYR*     3.8    31.4    -      -       +      +
    222A  LEU*     3.5    24.7    -      -       +      +
    225A  ALA*     3.9     9.6    -      -       +      -
    226A  ALA*     3.5    38.4    -      -       +      +
    229A  TYR*     4.1    14.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 174 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102A  VAL*     4.1    17.0    -      -       +      -
    105A  CYS*     3.6    44.6    -      -       +      -
    106A  VAL*     3.8    24.2    -      -       +      -
    109A  LEU*     4.3    16.4    -      -       +      +
    153A  ILE*     3.8    17.3    -      -       +      -
    154A  TYR*     3.5    20.0    -      -       +      +
    157A  LEU*     4.2    13.0    -      -       +      -
    170A  LEU*     2.9    37.3    +      -       +      +
    171A  ILE      3.8     2.9    -      -       -      +
    173A  LEU*     1.3    74.1    -      -       +      +
    175A  LEU*     1.3    63.8    +      -       -      +
    177A  SER*     3.1     6.4    +      -       -      -
    178A  SER*     2.9    28.4    +      -       -      -
    222A  LEU*     4.3    17.3    -      -       +      -
    226A  ALA*     4.9     2.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 175 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    150A  GLU*     5.8     3.4    -      -       -      +
    154A  TYR*     3.4    26.7    -      -       +      +
    171A  ILE*     3.0    40.0    +      -       +      +
    172A  GLU*     3.9     9.2    -      -       +      +
    174A  PHE*     1.3    75.5    -      -       -      +
    176A  GLN*     1.3    63.6    +      -       -      +
    178A  SER*     3.3     6.8    +      -       -      +
    179A  TYR*     3.0    22.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 176 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    172A  GLU      3.0    20.1    +      -       -      +
    173A  LEU*     3.9    11.8    -      -       -      +
    175A  LEU*     1.3    78.5    -      -       -      +
    177A  SER*     1.3    57.3    +      -       -      +
    179A  TYR*     3.2    10.4    +      -       +      +
    180A  GLN*     2.9    55.9    +      -       +      +
    221A  TYR*     5.6     4.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with SER 177 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    109A  LEU*     3.7     4.8    -      -       -      +
    173A  LEU*     2.9    19.1    +      -       -      -
    174A  PHE*     3.1    13.9    +      -       -      -
    176A  GLN*     1.3    77.6    -      -       -      +
    178A  SER*     1.3    55.6    +      -       -      +
    180A  GLN*     3.7    13.2    +      -       -      +
    181A  THR*     2.8    34.0    +      -       -      -
    217A  PHE*     4.7     4.3    -      -       -      +
    218A  TYR*     4.5     9.4    -      -       -      -
    221A  TYR*     6.3     1.6    -      -       -      -
    222A  LEU*     3.5    37.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 178 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    109A  LEU*     3.4    21.3    -      -       -      +
    112A  PHE*     5.2     0.2    -      -       -      -
    113A  PHE*     3.8    13.0    -      -       -      -
    150A  GLU*     4.4    10.6    +      -       -      +
    154A  TYR*     4.2     5.3    +      -       -      -
    174A  PHE      2.9    17.2    +      -       -      -
    175A  LEU*     3.4    11.0    -      -       -      -
    177A  SER*     1.3    72.8    +      -       -      +
    179A  TYR*     1.3    67.6    +      -       -      +
    181A  THR*     3.1     2.1    +      -       -      -
    182A  GLU*     2.9    41.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 179 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175A  LEU      3.0    10.4    +      -       -      +
    176A  GLN*     3.5    13.5    -      -       +      +
    178A  SER*     1.3    79.0    -      -       -      +
    180A  GLN*     1.3    74.1    +      -       +      +
    182A  GLU*     3.1    14.3    +      -       +      +
    183A  ILE*     3.0    56.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 180 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176A  GLN*     2.9    49.0    +      -       +      +
    177A  SER*     3.7    10.4    +      -       -      +
    179A  TYR*     1.3    86.5    -      -       +      +
    181A  THR*     1.3    63.4    +      -       -      +
    183A  ILE*     3.3     7.2    +      -       -      +
    184A  GLY      3.2    14.9    +      -       -      -
    213A  TYR*     3.1    24.8    -      -       +      +
    217A  PHE*     3.2    62.0    -      -       +      +
    221A  TYR*     5.7     0.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 181 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113A  PHE*     3.5    39.2    -      -       +      -
    177A  SER      2.8    22.4    +      -       -      -
    178A  SER      3.1     0.2    +      -       -      -
    180A  GLN*     1.3    78.5    -      -       -      +
    182A  GLU*     1.3    55.9    +      -       -      +
    184A  GLY*     3.4     2.3    +      -       -      -
    185A  GLN*     3.0    27.5    +      -       +      +
    213A  TYR      3.4     9.2    +      -       -      -
    214A  LYS*     3.5    20.1    -      -       -      +
    217A  PHE*     5.2     0.2    -      -       -      +
    218A  TYR*     3.5    29.1    +      -       +      +
    901A  RIS      4.1     7.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 182 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112A  PHE*     4.0    22.3    -      -       -      -
    113A  PHE*     3.6    17.5    -      -       +      -
    150A  GLU*     4.4     3.6    -      -       -      +
    178A  SER*     2.9    28.4    +      -       -      +
    179A  TYR*     3.6    15.9    -      -       +      +
    181A  THR*     1.3    72.8    -      -       -      +
    183A  ILE*     1.3    62.6    +      -       +      +
    185A  GLN*     3.8     8.0    -      -       +      +
    186A  THR*     2.9    30.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 183 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    179A  TYR*     3.0    57.8    +      -       +      +
    180A  GLN*     3.3    10.5    +      -       -      +
    182A  GLU*     1.3    77.9    -      -       +      +
    184A  GLY*     1.3    57.9    -      -       -      +
    186A  THR*     3.1    13.4    -      -       +      +
    187A  LEU*     3.0    35.8    +      -       +      +
    213A  TYR*     4.3    21.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 184 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    180A  GLN      3.2     7.7    +      -       -      -
    181A  THR      3.6     0.7    -      -       -      -
    183A  ILE*     1.3    76.5    -      -       -      +
    185A  GLN*     1.3    58.1    +      -       -      +
    187A  LEU*     3.2     7.7    +      -       -      +
    188A  ASP*     2.9    28.9    +      -       -      +
    210A  ILE*     4.1     5.7    -      -       -      +
    213A  TYR*     3.6    21.2    -      -       -      +
    214A  LYS*     3.6    20.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 185 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113A  PHE*     4.7     9.4    +      -       +      -
    117A  ASP*     2.7    35.8    +      -       -      +
    120A  MET*     4.1    17.6    -      -       +      +
    181A  THR*     3.0    26.1    +      -       +      +
    182A  GLU*     3.8     9.4    -      -       +      +
    184A  GLY*     1.3    71.3    -      -       -      +
    186A  THR*     1.3    65.4    +      -       -      +
    188A  ASP*     3.4     7.7    -      -       -      +
    189A  LEU*     3.1    40.1    +      -       +      +
    214A  LYS*     3.9    13.7    -      -       -      +
    901A  RIS      3.5    30.9    -      -       +      -
    909A   MG      4.3     2.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 186 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    182A  GLU      2.9    16.4    +      -       -      -
    183A  ILE*     3.1    19.0    -      -       +      +
    185A  GLN*     1.3    77.2    -      -       -      +
    187A  LEU*     1.3    66.7    +      -       +      +
    189A  LEU*     3.3     7.6    +      -       -      +
    190A  LEU*     3.1    43.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 187 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    183A  ILE*     3.0    25.2    +      -       +      +
    184A  GLY*     3.2     9.2    +      -       -      +
    186A  THR*     1.3    78.7    -      -       +      +
    188A  ASP*     1.3    64.5    +      -       -      +
    189A  LEU      3.0     0.3    +      -       -      -
    190A  LEU*     3.2    12.1    +      -       +      -
    191A  THR*     2.6    33.5    +      -       -      +
    206A  ARG*     4.0    26.7    -      -       -      +
    209A  SER*     4.2    34.3    -      -       -      +
    210A  ILE*     4.0    12.1    -      -       +      -
    213A  TYR*     4.9     5.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 188 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117A  ASP*     6.0     0.2    -      -       -      -
    184A  GLY      2.9    16.5    +      -       -      +
    185A  GLN*     3.4    21.4    -      -       -      +
    187A  LEU*     1.3    73.2    -      -       -      +
    189A  LEU*     1.3    66.1    +      -       -      +
    191A  THR*     3.6     2.6    +      -       -      -
    192A  ALA*     3.3    24.1    +      -       -      +
    210A  ILE*     4.1    21.8    -      -       +      +
    214A  LYS*     3.1    30.0    +      -       +      +
    280A  LYS*     3.0    39.2    +      -       -      +
    281A  CYS*     5.5     2.4    +      -       -      +
    901A  RIS      5.3     0.7    -      -       -      -
    909A   MG      4.2     5.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 189 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    120A  MET*     4.0    48.0    -      -       +      +
    121A  ASP*     4.4     1.6    -      -       -      +
    185A  GLN*     3.1    33.7    +      -       +      +
    186A  THR*     3.9     6.3    -      -       -      +
    187A  LEU      3.1     0.2    -      -       -      -
    188A  ASP*     1.3    78.4    -      -       -      +
    190A  LEU*     1.3    63.3    +      -       +      +
    192A  ALA*     3.4    23.1    +      -       -      +
    193A  PRO*     3.8     2.9    -      -       -      +
    280A  LYS*     3.8    21.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 190 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    186A  THR*     3.1    40.0    +      -       +      +
    187A  LEU*     3.8    15.7    -      -       +      +
    189A  LEU*     1.3    73.4    -      -       -      +
    191A  THR*     1.3    63.9    +      -       -      +
    192A  ALA      3.2     0.9    -      -       -      -
    193A  PRO*     3.6    12.1    -      -       -      +
    201A  ARG*     4.6     4.9    -      -       -      -
    206A  ARG*     4.6     8.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 191 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    187A  LEU      2.6    22.7    +      -       -      -
    188A  ASP      4.0     4.0    -      -       -      -
    190A  LEU*     1.3    75.4    -      -       -      +
    192A  ALA*     1.3    56.4    +      -       -      +
    193A  PRO*     3.3    10.1    -      -       -      +
    198A  ASP*     3.5     6.8    -      -       -      +
    201A  ARG*     3.6    25.5    -      -       +      +
    202A  PHE*     3.4    19.8    -      -       +      -
    206A  ARG*     3.0    43.2    +      -       +      +
    210A  ILE*     4.0     6.6    -      -       -      +
    281A  CYS*     4.0    22.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 192 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188A  ASP      3.3    18.1    +      -       -      +
    189A  LEU*     3.4    10.0    -      -       -      +
    190A  LEU      3.2     0.2    -      -       -      -
    191A  THR*     1.3    79.0    -      -       -      +
    193A  PRO*     1.3    64.5    -      -       -      +
    194A  GLN*     3.4     4.7    +      -       -      +
    278A  ASP      3.9     8.2    -      -       -      +
    279A  ASN*     3.0    32.5    -      -       -      +
    280A  LYS*     3.9    21.9    +      -       +      +
    281A  CYS      4.8     0.7    -      -       -      +
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il