Contacts of the helix formed by residues 158 - 180 (chain A) in PDB entry 2HKU


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 GLY 158 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    155A  LEU*     4.6     3.4    -      -       -      -
    157A  ALA*     1.3    78.1    -      -       -      +
    159A  ILE*     1.3    60.7    +      -       -      -
    160A  ASP*     3.2    12.1    -      -       -      -
    161A  VAL*     3.0    23.1    +      -       -      +
    162A  GLU*     3.2     7.4    +      -       -      +
    303A  EDO      4.1     6.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 159 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    141A  GLU*     3.5    48.3    -      -       +      +
    145A  ILE*     3.4    17.8    -      -       +      +
    146A  ARG*     4.8     3.1    -      -       +      +
    149A  MSE      3.8    22.4    -      -       +      -
    155A  LEU*     4.1    19.9    -      -       +      +
    157A  ALA      3.7     0.8    +      -       -      -
    158A  GLY*     1.3    67.0    -      -       -      -
    160A  ASP*     1.3    70.5    +      -       +      +
    162A  GLU*     3.4     3.1    +      -       -      +
    163A  SER*     3.1    17.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 160 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137A  HIS*     5.6     0.7    -      -       -      +
    141A  GLU*     3.3    23.1    -      -       -      +
    158A  GLY*     3.5    14.0    -      -       -      -
    159A  ILE*     1.3    77.5    +      -       +      +
    161A  VAL*     1.4    78.3    +      -       -      +
    163A  SER*     3.2     6.8    +      -       -      -
    164A  LYS*     3.1    35.8    +      -       -      +
    190B  GLU*     4.7     8.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 161 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    157A  ALA*     3.7    23.1    -      -       +      -
    158A  GLY*     3.0    12.3    +      -       -      +
    160A  ASP*     1.4    84.7    -      -       -      +
    162A  GLU*     1.3    60.9    +      -       -      +
    164A  LYS*     3.2     9.3    +      -       +      +
    165A  ALA*     2.8    28.2    +      -       +      +
    190B  GLU*     4.1    22.7    -      -       +      +
    193B  ALA*     4.0    32.5    -      -       +      +
    194B  VAL*     4.3    10.2    -      -       +      +
    197B  ALA*     5.3     1.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 162 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    145A  ILE*     3.9    24.6    -      -       +      +
    153A  TRP*     3.4    10.5    -      -       -      -
    155A  LEU*     4.0    10.1    -      -       +      -
    156A  ARG*     2.8    63.3    +      -       -      +
    157A  ALA*     3.0    28.3    +      -       +      +
    158A  GLY      3.2     4.1    +      -       -      +
    159A  ILE      3.8     6.5    -      -       -      +
    160A  ASP      3.3     0.4    -      -       -      -
    161A  VAL*     1.3    77.0    -      -       -      +
    163A  SER*     1.3    62.2    +      -       -      +
    165A  ALA*     3.5     7.0    +      -       -      +
    166A  PHE*     3.0    22.9    +      -       -      +
    199A  LEU*     5.2     2.4    -      -       -      +
    197B  ALA*     4.4     7.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 163 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137A  HIS*     2.6    39.1    +      -       -      -
    140A  GLY*     3.2    16.7    -      -       -      -
    141A  GLU*     3.7    18.8    -      -       -      -
    145A  ILE*     4.0     7.3    -      -       -      +
    159A  ILE      3.1     6.6    +      -       -      -
    160A  ASP      3.2     8.3    +      -       -      -
    162A  GLU*     1.3    78.5    -      -       -      +
    164A  LYS*     1.3    56.0    +      -       -      +
    166A  PHE*     3.3     5.9    +      -       -      +
    167A  TRP*     2.9    30.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 164 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137A  HIS*     3.7    44.4    +      -       +      +
    160A  ASP*     3.1    27.6    +      -       -      +
    161A  VAL*     3.2     8.7    +      -       +      +
    163A  SER*     1.3    72.6    -      -       -      +
    165A  ALA*     1.3    55.0    +      -       -      +
    167A  TRP*     4.3     0.2    -      -       -      +
    168A  SER*     2.8    38.3    +      -       -      -
    173B  LEU*     5.3     4.3    -      -       +      +
    176B  GLN*     4.9     1.9    +      -       -      +
    190B  GLU*     2.5    48.4    +      -       +      +
    194B  VAL*     4.5    10.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 165 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    156A  ARG*     5.6     0.2    -      -       -      +
    161A  VAL      2.8    16.8    +      -       -      +
    162A  GLU*     3.7    13.0    -      -       -      +
    163A  SER      3.3     0.2    -      -       -      -
    164A  LYS*     1.3    75.3    -      -       -      +
    166A  PHE*     1.3    62.9    +      -       -      +
    168A  SER*     3.5     0.7    +      -       -      -
    169A  ALA*     3.3    23.9    +      -       -      +
    198A  ASN*     4.9     0.7    -      -       -      +
    194B  VAL*     3.7    30.4    -      -       +      +
    197B  ALA*     5.0     4.3    -      -       +      -
    198B  ASN*     3.5    27.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 166 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97A  LEU*     3.6    21.1    -      -       +      -
     98A  VAL*     3.8    11.0    -      -       +      -
    101A  LEU*     3.8     6.7    -      -       +      -
    140A  GLY*     5.8     0.4    -      -       -      -
    144A  LEU*     3.3    28.5    -      -       +      -
    145A  ILE*     5.0     3.1    -      -       +      -
    162A  GLU      3.0    14.7    +      -       -      +
    163A  SER*     3.5    10.1    -      -       -      +
    164A  LYS      3.2     0.2    -      -       -      -
    165A  ALA*     1.3    79.3    -      -       -      +
    167A  TRP*     1.3    81.2    +      +       -      +
    169A  ALA*     3.6     4.1    -      -       -      +
    170A  ILE*     3.0    52.4    +      -       +      +
    195A  ILE*     3.8    31.2    -      -       +      -
    199A  LEU*     4.8     7.6    -      -       +      -
    302A  EDO      3.7    28.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 167 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  VAL*     4.5     9.0    -      -       +      -
     77A  GLY*     4.5     7.4    -      -       -      -
    101A  LEU*     4.0    24.2    -      -       +      -
    109A  VAL*     4.7     3.6    -      -       +      -
    136A  LEU*     3.1    55.1    +      -       +      -
    137A  HIS*     3.6    25.6    -      +       +      +
    139A  SER*     4.9     0.2    -      -       -      -
    140A  GLY*     4.9     0.2    -      -       -      -
    163A  SER*     2.9    30.8    +      -       -      +
    164A  LYS      4.3     0.2    -      -       -      +
    166A  PHE*     1.3    82.8    -      +       -      +
    168A  SER*     1.3    57.3    +      -       -      +
    170A  ILE*     3.3    22.2    +      -       +      +
    171A  PHE*     3.0    68.8    +      +       +      -
    302A  EDO      2.9    38.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 168 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    164A  LYS      2.8    23.4    +      -       -      -
    165A  ALA*     3.5     8.5    +      -       -      -
    167A  TRP*     1.3    73.1    -      -       -      +
    169A  ALA*     1.3    56.8    +      -       -      +
    171A  PHE*     3.5    10.8    +      -       -      -
    172A  GLY      3.0    23.4    +      -       -      -
    168B  SER      3.2    10.3    -      -       -      +
    169B  ALA*     4.0     4.7    +      -       -      +
    172B  GLY*     3.3    15.5    -      -       -      -
    173B  LEU*     4.0    13.4    -      -       -      +
    176B  GLN*     3.6    17.0    -      -       -      +
    194B  VAL*     4.0    12.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 169 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    165A  ALA      3.3    17.2    +      -       -      +
    166A  PHE*     3.6     1.1    -      -       -      +
    167A  TRP      3.3     0.2    -      -       -      -
    168A  SER*     1.3    77.3    +      -       -      +
    170A  ILE*     1.3    60.4    +      -       -      +
    172A  GLY      3.7     0.2    -      -       -      -
    173A  LEU*     2.7    42.4    +      -       +      +
    194A  VAL*     5.3     0.4    -      -       +      -
    195A  ILE*     3.4    24.2    -      -       +      -
    198A  ASN*     3.5    17.0    -      -       -      +
    165B  ALA*     5.9     0.9    -      -       -      +
    168B  SER*     4.4    13.7    -      -       -      -
    169B  ALA*     4.6     2.8    -      -       -      +
    198B  ASN*     4.8     3.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 170 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     98A  VAL*     4.6     4.0    -      -       +      -
    101A  LEU*     4.2    18.4    -      -       +      -
    102A  LEU*     3.9    22.4    -      -       +      -
    109A  VAL*     4.2    13.0    -      -       +      -
    166A  PHE*     3.0    52.7    +      -       +      +
    167A  TRP*     3.3    30.5    +      -       +      +
    169A  ALA*     1.3    74.6    -      -       -      +
    171A  PHE*     1.3    58.4    +      -       -      +
    173A  LEU*     3.8     2.9    -      -       -      +
    174A  VAL*     2.9    36.9    +      -       +      +
    195A  ILE*     3.9    18.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 171 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  VAL*     4.9     0.4    -      -       +      -
    109A  VAL*     3.6    21.5    -      -       +      -
    112A  PHE*     4.0    18.8    -      +       -      -
    113A  THR*     4.1     8.5    -      -       +      +
    116A  MSE      4.0     9.9    -      -       +      -
    133A  LEU*     3.8    31.6    -      -       +      -
    136A  LEU*     4.0     8.7    -      -       +      -
    167A  TRP*     3.0    59.5    +      +       +      -
    168A  SER*     3.7     5.2    -      -       -      +
    169A  ALA      3.3     0.4    -      -       -      -
    170A  ILE*     1.3    73.7    -      -       -      +
    172A  GLY*     1.3    57.2    +      -       -      +
    174A  VAL*     3.8     1.9    -      -       -      +
    175A  ILE*     2.9    36.3    +      -       -      +
    172B  GLY*     3.9    18.8    -      -       -      -
    175B  ILE*     3.8    16.4    -      -       +      -
    176B  GLN*     3.9    10.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 172 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168A  SER      3.0    11.3    +      -       -      -
    169A  ALA      3.8     0.2    -      -       -      -
    171A  PHE*     1.3    77.1    -      -       -      +
    173A  LEU*     1.3    60.9    +      -       -      +
    175A  ILE*     3.6     3.2    +      -       -      +
    176A  GLN*     2.9    37.3    +      -       -      +
    168B  SER*     3.4    25.4    -      -       -      -
    171B  PHE*     4.3     8.3    -      -       -      -
    172B  GLY*     4.0     7.3    -      -       -      -
----------------------------------------------------------
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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
----------------------------------------------------------
    102A  LEU*     4.1    13.9    -      -       +      -
    169A  ALA*     2.7    28.6    +      -       +      +
    170A  ILE*     3.9     3.1    -      -       -      +
    172A  GLY*     1.3    71.9    -      -       -      +
    174A  VAL*     1.3    59.4    +      -       -      +
    176A  GLN*     4.1     0.8    -      -       -      +
    177A  LYS*     2.8    35.2    +      -       -      +
    186A  TYR*     3.4    24.6    -      -       +      -
    191A  ALA*     3.7    29.2    -      -       +      +
    194A  VAL*     3.9    20.2    -      -       +      -
    195A  ILE*     3.6    34.8    -      -       +      -
    168B  SER*     3.3    19.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 174 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    101A  LEU      4.3     1.8    -      -       -      +
    102A  LEU*     3.8    19.1    -      -       +      -
    106A  ALA*     3.7    27.1    -      -       +      +
    109A  VAL*     3.7    24.5    -      -       +      -
    110A  GLU*     3.6    38.1    -      -       +      +
    113A  THR*     5.5     0.2    -      -       +      -
    170A  ILE*     2.9    22.0    +      -       +      +
    171A  PHE      3.8     3.6    -      -       -      +
    173A  LEU*     1.3    76.0    -      -       -      +
    175A  ILE*     1.3    65.7    +      -       +      +
    177A  LYS*     4.0     7.0    +      -       -      +
    178A  THR*     3.2    21.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 175 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113A  THR*     3.9    22.4    -      -       +      +
    117A  LEU*     6.1     0.2    -      -       +      -
    171A  PHE      2.9    26.6    +      -       -      +
    172A  GLY*     4.0     7.9    -      -       -      +
    173A  LEU      3.3     0.2    -      -       -      -
    174A  VAL*     1.3    78.6    -      -       +      +
    176A  GLN*     1.3    57.3    +      -       +      +
    178A  THR*     2.9    26.9    -      -       -      +
    179A  ALA*     3.0    10.4    +      -       -      +
    113B  THR*     4.5     8.3    -      -       -      +
    116B  MSE      3.8    39.5    -      -       +      -
    117B  LEU*     4.3    14.1    -      -       +      -
    171B  PHE*     4.8     7.2    -      -       +      +
    175B  ILE*     3.8    39.0    -      -       +      -
----------------------------------------------------------
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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  GLY      2.9    23.5    +      -       -      +
    173A  LEU      4.1     0.2    -      -       -      +
    175A  ILE*     1.3    73.9    -      -       -      +
    177A  LYS*     1.3    58.1    +      -       -      +
    179A  ALA*     4.4     1.1    -      -       -      -
    180A  THR*     2.5    40.5    +      -       -      +
    186A  TYR*     3.3    28.3    +      -       +      -
    116B  MSE      3.9    24.5    -      -       +      -
    133B  LEU*     3.5    13.0    -      -       +      +
    137B  HIS*     3.3    29.3    -      -       -      -
    168B  SER*     3.1    31.5    +      -       -      +
    171B  PHE*     3.5    15.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 177 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102A  LEU*     2.7    46.9    +      -       -      +
    106A  ALA*     3.9    13.1    -      -       -      +
    173A  LEU      2.8    22.0    +      -       -      +
    174A  VAL*     4.0     5.6    +      -       -      +
    176A  GLN*     1.3    79.4    -      -       -      +
    178A  THR*     1.3    57.6    -      -       -      +
    180A  THR*     3.1     6.7    +      -       -      -
    182A  GLU*     2.7    60.8    +      -       +      +
    186A  TYR*     3.4    24.3    -      -       +      +
    187A  SER      3.9     1.8    -      -       -      +
    188A  LEU*     3.9    21.9    -      -       +      +
    191A  ALA*     4.4    11.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 178 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110A  GLU*     3.1    29.1    +      -       -      +
    174A  VAL*     3.2    15.0    +      -       -      +
    175A  ILE*     2.9    19.1    -      -       -      +
    177A  LYS*     1.3    74.6    -      -       -      +
    179A  ALA*     1.3    72.3    +      -       +      +
    181A  GLY*     3.3    11.5    +      -       -      -
    182A  GLU*     5.8     1.6    -      -       -      -
    116B  MSE      4.5     3.6    -      -       -      +
    117B  LEU*     4.1    20.6    -      -       +      -
    119B  THR*     4.9     3.2    +      -       -      -
    126B  ARG*     4.0     8.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 179 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175A  ILE      3.0    12.2    +      -       -      +
    176A  GLN*     4.1     3.8    -      -       -      +
    178A  THR*     1.3    83.4    -      -       -      +
    180A  THR*     1.3    57.5    +      -       +      +
    181A  GLY      3.2     0.9    -      -       -      -
    116B  MSE      3.4    47.8    -      -       +      +
    119B  THR*     4.2    11.1    +      -       +      +
    126B  ARG*     3.3    25.5    +      -       -      +
    129B  ILE*     4.0    10.9    -      -       +      +
    130B  THR*     4.5     1.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 180 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176A  GLN      2.5    28.8    +      -       -      +
    177A  LYS*     3.1    11.1    +      -       -      -
    178A  THR      3.3     0.2    -      -       -      -
    179A  ALA*     1.3    75.0    -      -       -      +
    181A  GLY*     1.3    62.1    +      -       -      +
    182A  GLU      3.4     2.8    +      -       -      -
    183A  SER*     3.2    30.8    +      -       -      +
    184A  PHE*     3.6    26.2    -      -       +      +
    186A  TYR*     3.8     8.1    -      -       +      +
    126B  ARG*     3.9     9.8    +      -       -      -
    129B  ILE*     5.6     0.2    -      -       +      -
    130B  THR*     4.1    17.9    -      -       +      -
    133B  LEU*     3.6    28.5    -      -       +      -
----------------------------------------------------------
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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