Contacts of the helix formed by residues 131 - 159 (chain A) in PDB entry 3O8H


Residue contacts within the protein are derived with the CSU software (Sobolev V., Sorokine A., Prilusky J., Abola E.E. and Edelman M. (1999) Automated analysis of interatomic contacts in proteins. Bioinformatics, 15, 327-332). A short description of the analytical approach is given at the end of the page.
For CSU analysis of other PDB entry

Note:
Non-standard 3 letter residue codes indicate a heterogroup. To identify and analyse, use LPC software

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with SER 131 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     69A  GLU*     6.1     6.3    -      -       -      -
     73A  LEU*     5.7     0.3    -      -       -      +
    127A  ALA*     2.9    19.6    +      -       -      +
    128A  ARG      3.5     9.7    -      -       -      +
    129A  ALA      3.7     0.6    -      -       -      -
    130A  THR*     1.3    81.3    -      -       -      +
    132A  VAL*     1.3    59.1    +      -       -      +
    133A  GLU*     3.5    14.7    +      -       -      +
    134A  VAL*     3.0    30.6    +      -       -      +
    135A  ALA*     2.9    23.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 132 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    130A  THR      4.2     0.8    +      -       -      -
    131A  SER*     1.3    73.6    +      -       -      +
    133A  GLU*     1.3    77.1    +      -       +      +
    135A  ALA*     3.8     6.3    -      -       -      +
    136A  GLU*     2.8    37.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 133 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  LEU*     3.7    32.2    -      -       +      +
    131A  SER*     3.5    12.1    +      -       -      +
    132A  VAL*     1.3    92.4    +      -       +      +
    134A  VAL*     1.3    62.6    +      -       -      +
    136A  GLU*     3.9     7.3    -      -       -      +
    137A  LEU*     2.9    28.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 134 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     69A  GLU      5.6     1.8    -      -       -      +
     72A  LEU*     5.3     4.9    -      -       +      -
     73A  LEU*     3.9    32.1    -      -       +      +
     76A  LEU*     4.3    17.9    -      -       +      +
    124A  GLY*     3.4    26.7    -      -       -      +
    127A  ALA*     3.8    13.0    -      -       +      +
    128A  ARG*     3.8    14.1    -      -       +      +
    131A  SER*     3.0    30.1    +      -       -      +
    133A  GLU*     1.3    74.9    -      -       -      +
    135A  ALA*     1.3    62.3    +      -       -      +
    137A  LEU*     3.2     3.5    +      -       -      +
    138A  TRP*     3.0    23.0    +      -       -      +
    217A  O8H      5.3     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 135 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128A  ARG*     3.6    34.6    +      -       +      +
    131A  SER      2.9    11.7    +      -       -      +
    132A  VAL*     3.9     7.2    -      -       -      +
    134A  VAL*     1.3    75.9    -      -       -      +
    136A  GLU*     1.3    57.4    +      -       -      +
    138A  TRP*     3.5     1.8    +      -       -      +
    139A  SER*     2.9    32.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 136 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132A  VAL*     2.8    24.7    +      -       -      +
    133A  GLU*     3.9     6.3    -      -       -      +
    135A  ALA*     1.3    74.8    -      -       -      +
    137A  LEU*     1.3    60.7    +      -       -      +
    139A  SER*     3.8     5.0    -      -       -      -
    140A  THR*     2.8    42.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 137 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  LEU*     4.1    13.9    -      -       +      -
     76A  LEU*     3.4    29.2    -      -       +      +
     77A  ASP*     3.5    47.8    -      -       +      +
     80A  VAL*     4.7     4.7    -      -       +      +
    133A  GLU      2.9    18.5    +      -       -      +
    134A  VAL      3.2     4.5    +      -       -      +
    136A  GLU*     1.3    78.9    -      -       -      +
    138A  TRP*     1.3    63.1    +      -       -      +
    140A  THR*     3.4     4.0    +      -       -      -
    141A  PHE*     3.2    56.4    +      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 138 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76A  LEU*     4.8     2.2    -      -       +      +
     80A  VAL*     3.7    29.2    -      -       +      -
    114A  PHE*     3.7     6.3    -      +       -      -
    128A  ARG*     3.3    39.2    -      -       +      +
    134A  VAL      3.0    15.7    +      -       -      +
    135A  ALA      3.9     2.9    -      -       -      +
    137A  LEU*     1.3    78.1    -      -       -      +
    139A  SER*     1.3    59.1    +      -       -      +
    141A  PHE*     3.3     3.3    +      -       +      -
    142A  MET*     2.9    55.8    +      -       +      +
    145A  TRP*     3.9    15.3    -      +       -      -
    180A  GLU*     2.8    24.7    +      -       +      -
    217A  O8H      3.3    80.1    -      +       +      -
----------------------------------------------------------
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Residues in contact with SER 139 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135A  ALA      2.9    19.2    +      -       -      -
    136A  GLU*     3.8     5.4    -      -       -      -
    138A  TRP*     1.3    79.8    -      -       -      +
    140A  THR*     1.3    60.9    +      -       -      +
    142A  MET*     3.4     5.9    +      -       -      +
    143A  GLN*     3.0    46.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 140 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    136A  GLU*     2.8    33.9    +      -       -      +
    137A  LEU*     3.7     6.2    -      -       -      -
    139A  SER*     1.3    72.0    +      -       -      +
    141A  PHE*     1.3    74.6    +      -       +      +
    143A  GLN*     3.5    12.0    +      -       -      +
    144A  LYS*     3.2    33.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 141 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77A  ASP*     5.1     0.2    -      -       -      -
     80A  VAL*     3.4    26.7    -      -       +      -
     81A  ASN*     3.5    27.4    -      -       -      -
     84A  ASP*     3.6    30.3    -      -       +      -
    137A  LEU*     3.2    35.7    +      -       +      +
    138A  TRP*     4.0     3.8    -      -       +      +
    140A  THR*     1.3    88.7    -      -       +      +
    142A  MET*     1.3    66.2    +      -       -      +
    144A  LYS*     3.1    24.1    +      -       -      +
    145A  TRP*     2.9    58.7    +      +       +      -
----------------------------------------------------------
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Residues in contact with MET 142 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    138A  TRP*     2.9    61.1    +      -       +      +
    139A  SER*     3.8     6.3    -      -       -      +
    141A  PHE*     1.3    75.1    -      -       -      +
    143A  GLN*     1.3    58.7    +      -       +      +
    145A  TRP*     3.3    17.5    +      -       +      +
    146A  ILE*     2.8    45.3    +      -       +      +
    176A  ASN*     3.6    43.5    -      -       +      +
    177A  LEU*     4.1    11.4    -      -       +      -
    180A  GLU*     3.5    17.3    -      -       +      +
    217A  O8H      4.0     7.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 143 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    139A  SER*     3.0    40.7    +      -       -      +
    140A  THR*     3.8     9.5    +      -       -      +
    142A  MET*     1.3    75.6    -      -       +      +
    144A  LYS*     1.3    58.0    +      -       -      +
    146A  ILE*     3.8     8.1    -      -       +      +
    147A  ALA*     2.9    30.5    +      -       -      +
    169A  HIS*     5.3     1.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 144 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84A  ASP*     3.5    23.8    -      -       -      +
     88A  GLN*     5.7     1.8    -      -       +      +
    140A  THR*     3.2    25.6    +      -       -      +
    141A  PHE*     3.1    41.4    +      -       -      +
    143A  GLN*     1.3    77.0    -      -       -      +
    145A  TRP*     1.3    58.4    +      -       +      +
    147A  ALA*     3.4     6.9    +      -       -      +
    148A  TYR*     2.9    27.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with TRP 145 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80A  VAL*     3.9    19.3    -      -       +      -
     84A  ASP*     2.8    31.4    +      -       -      +
     87A  LEU*     3.7    17.9    -      -       +      +
    110A  PHE*     3.5    34.4    -      +       -      -
    114A  PHE*     4.2    16.6    -      +       -      -
    138A  TRP*     3.9    24.2    -      +       -      -
    141A  PHE*     2.9    47.0    +      +       +      +
    142A  MET*     3.9    21.1    -      -       -      +
    144A  LYS*     1.3    77.1    -      -       +      +
    146A  ILE*     1.3    60.4    +      -       -      +
    148A  TYR*     3.3     6.1    +      -       +      +
    149A  THR*     3.0    33.7    +      -       -      -
    176A  ASN*     4.0     4.7    -      -       -      +
    217A  O8H      3.8    24.5    -      +       -      +
----------------------------------------------------------
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Residues in contact with ILE 146 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    142A  MET*     2.8    36.2    +      -       +      +
    143A  GLN*     3.8     6.7    -      -       +      +
    145A  TRP*     1.3    73.1    -      -       -      +
    147A  ALA*     1.3    59.2    +      -       -      +
    149A  THR*     3.2     3.1    +      -       -      -
    150A  ALA*     2.8    28.4    +      -       -      +
    169A  HIS*     3.5    23.6    -      -       +      +
    172A  ALA*     3.6     4.2    -      -       +      +
    173A  THR*     3.4    51.4    -      -       +      +
    176A  ASN*     3.5    35.4    -      -       +      +
    177A  LEU*     5.3     3.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 147 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    143A  GLN      2.9    18.8    +      -       -      +
    144A  LYS*     3.7     6.5    -      -       -      +
    146A  ILE*     1.3    75.3    -      -       -      +
    148A  TYR*     1.3    58.9    +      -       -      +
    150A  ALA*     3.3     7.4    +      -       -      +
    151A  ALA*     2.9    28.6    +      -       -      +
    169A  HIS*     4.5    11.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 148 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87A  LEU*     4.1    24.0    -      -       +      -
     91A  ALA*     3.1    40.1    +      -       +      +
    144A  LYS*     2.9    17.6    +      -       +      +
    145A  TRP*     3.8     7.4    -      -       +      +
    147A  ALA*     1.3    72.1    -      -       -      +
    149A  THR*     1.3    66.7    +      -       -      +
    151A  ALA*     3.1    11.6    +      -       +      +
    152A  VAL*     2.9    38.1    +      -       +      +
    217A  O8H      3.0    52.6    -      +       -      -
----------------------------------------------------------
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Residues in contact with THR 149 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103A  TRP*     4.1     4.2    -      -       +      -
    145A  TRP      3.0    14.8    +      -       -      -
    146A  ILE      3.5     7.9    -      -       -      -
    148A  TYR*     1.3    74.7    -      -       -      +
    150A  ALA*     1.3    57.7    +      -       -      +
    152A  VAL*     3.3     4.9    +      -       -      +
    153A  ILE*     2.9    40.4    +      -       +      +
    172A  ALA*     3.6    19.1    -      -       +      -
    175A  LEU*     5.3     0.7    -      -       +      -
    176A  ASN*     3.0    18.0    +      -       -      +
    207A  TRP*     3.5    24.7    -      -       +      -
    217A  O8H      3.5    26.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 150 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    146A  ILE      2.8    16.3    +      -       -      +
    147A  ALA*     3.7     4.0    -      -       -      +
    149A  THR*     1.3    77.7    -      -       -      +
    151A  ALA*     1.3    56.7    +      -       -      +
    153A  ILE*     3.3     5.7    +      -       -      +
    154A  ASP*     2.8    37.4    +      -       -      +
    168A  ALA*     3.9     8.8    -      -       +      +
    169A  HIS*     3.9    40.4    -      -       +      +
    172A  ALA*     3.8     5.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 151 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    147A  ALA      2.9    16.6    +      -       -      +
    148A  TYR*     3.6    14.1    -      -       +      +
    150A  ALA*     1.3    78.2    -      -       -      +
    152A  VAL*     1.3    56.9    +      -       +      +
    154A  ASP*     3.4    11.3    +      -       -      +
    155A  ALA*     3.0    27.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 152 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102A  MET*     3.8    22.9    -      -       +      -
    103A  TRP*     3.4    32.8    -      -       +      -
    148A  TYR*     2.9    53.6    +      -       +      +
    149A  THR      3.8     2.5    -      -       -      +
    151A  ALA*     1.3    73.3    -      -       -      +
    153A  ILE*     1.3    65.2    +      -       -      +
    155A  ALA*     3.2     8.4    +      -       +      +
    156A  GLU*     3.0    23.4    +      -       +      +
    217A  O8H      3.8     9.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 153 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103A  TRP*     4.2     4.7    -      -       +      -
    149A  THR*     2.9    35.5    +      -       +      +
    150A  ALA      3.5     6.3    -      -       -      +
    152A  VAL*     1.3    76.8    -      -       -      +
    154A  ASP*     1.3    57.6    +      -       -      +
    156A  GLU*     3.2     9.6    +      -       -      +
    157A  ARG*     2.9    56.6    +      -       +      +
    162A  ALA*     5.6     0.2    -      -       +      -
    168A  ALA*     3.6    30.1    -      -       +      +
    171A  LEU*     4.2    14.4    -      -       +      -
    172A  ALA*     4.3     1.8    -      -       -      +
    175A  LEU*     4.9     0.4    -      -       +      -
    211A  ILE*     4.1    41.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 154 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    150A  ALA*     2.8    28.5    +      -       -      +
    151A  ALA*     3.5    10.0    -      -       -      +
    153A  ILE*     1.3    71.3    -      -       -      +
    155A  ALA*     1.3    59.0    +      -       -      +
    157A  ARG*     3.3    11.0    +      -       -      +
    158A  ASP*     2.8    41.2    +      -       -      +
    164A  ARG*     5.3     4.1    +      -       -      +
    168A  ALA*     3.5    19.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 155 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    151A  ALA      3.0    13.8    +      -       -      +
    152A  VAL*     3.2    12.3    +      -       +      +
    154A  ASP*     1.3    77.2    -      -       -      +
    156A  GLU*     1.3    58.5    +      -       -      +
    158A  ASP*     3.2     8.4    +      -       -      +
    159A  ARG*     2.9    34.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 156 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     99A  ARG*     4.2     0.5    -      -       -      +
    102A  MET*     4.0    20.9    -      -       +      +
    103A  TRP*     4.7     2.5    -      -       +      -
    152A  VAL*     3.0    20.1    +      -       +      +
    153A  ILE*     3.2    12.1    +      -       -      +
    155A  ALA*     1.3    76.9    -      -       -      +
    157A  ARG*     1.3    58.5    +      -       -      +
    159A  ARG*     2.7    48.7    +      -       -      +
    160A  GLY      3.3     2.4    +      -       -      -
    161A  ALA*     2.9    29.0    +      -       -      -
    162A  ALA*     3.0    20.3    +      -       +      -
    211A  ILE*     5.2     0.7    -      -       +      -
    212A  TYR*     2.6    34.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 157 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    153A  ILE*     2.9    35.5    +      -       -      +
    154A  ASP*     3.6    12.5    +      -       -      +
    156A  GLU*     1.3    74.6    -      -       -      +
    158A  ASP*     1.3    60.0    +      -       -      +
    160A  GLY*     3.0    18.5    +      -       -      -
    162A  ALA*     3.4    27.9    -      -       +      +
    163A  PRO      3.4    14.4    +      -       -      +
    164A  ARG*     3.5    43.1    +      -       +      +
    165A  THR*     3.3    26.2    +      -       -      +
    166A  LEU      2.6    31.5    +      -       -      +
    167A  PRO*     4.5     1.2    -      -       -      +
    168A  ALA*     3.6    16.1    -      -       -      +
    171A  LEU*     4.2    16.4    -      -       -      +
    211A  ILE      5.4     2.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 158 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    154A  ASP*     2.8    28.4    +      -       -      +
    155A  ALA*     3.2     8.6    +      -       -      +
    157A  ARG*     1.3    72.8    -      -       -      +
    159A  ARG*     1.3    59.0    +      -       -      +
    160A  GLY*     3.6     0.5    +      -       -      -
    164A  ARG*     2.7    33.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 159 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     99A  ARG*     4.6    14.5    -      -       -      +
    102A  MET*     5.8     0.2    -      -       -      +
    155A  ALA      2.9    19.0    +      -       -      +
    156A  GLU*     2.7    48.1    +      -       -      +
    158A  ASP*     1.3    78.5    -      -       -      +
    160A  GLY*     1.3    55.9    +      -       -      +
    161A  ALA*     3.3    22.9    +      -       +      +
----------------------------------------------------------
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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