Contacts of the helix formed by residues 130 - 154 (chain H) in PDB entry 2EHO


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 GLU 130 (chain H).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     88H  LEU*     2.9    40.3    -      -       +      +
     93H  GLN*     5.4     2.5    -      -       -      +
     94H  GLU*     5.0     4.2    +      -       -      +
     97H  ARG*     3.5    29.0    +      -       -      +
    128H  SER*     2.9    15.4    +      -       -      +
    129H  PRO*     1.3    85.0    -      -       +      +
    131H  ASN*     1.3    56.4    +      -       -      +
    132H  ALA      3.5     2.5    -      -       -      -
    133H  ASP*     3.3    15.5    +      -       -      +
    134H  ILE*     3.0    28.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 131 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    174G  LEU*     4.0    12.4    -      -       +      +
    123H  LEU      4.6     1.0    +      -       -      -
    124H  LEU*     2.9    55.5    +      -       -      +
    127H  ASP*     4.2     3.8    -      -       -      -
    128H  SER*     3.2    36.0    +      -       -      +
    129H  PRO      3.3     1.8    -      -       -      -
    130H  GLU*     1.3    74.2    -      -       -      +
    132H  ALA*     1.3    68.5    +      -       -      +
    134H  ILE*     3.0     9.6    +      -       -      +
    135H  SER*     2.8    24.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 132 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    174G  LEU*     3.8    15.1    -      -       +      +
    129H  PRO      5.0     0.8    +      -       -      -
    130H  GLU      3.5     0.4    -      -       -      -
    131H  ASN*     1.3    77.3    -      -       -      +
    133H  ASP*     1.3    59.3    +      -       -      +
    135H  SER*     3.3     2.3    +      -       -      -
    136H  GLN*     3.0    30.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 133 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97H  ARG*     3.6    27.2    +      -       -      +
    129H  PRO      4.9     1.6    -      -       -      +
    130H  GLU*     3.3    21.6    +      -       -      +
    131H  ASN      3.1     0.4    -      -       -      -
    132H  ALA*     1.3    77.8    -      -       -      +
    134H  ILE*     1.3    66.1    +      -       -      +
    136H  GLN*     3.4     8.1    +      -       -      +
    137H  SER*     3.0    23.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 134 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     88H  LEU*     3.5    30.7    -      -       +      -
     92H  TYR*     4.1    25.1    -      -       +      +
     97H  ARG*     3.9    23.5    -      -       -      +
    120H  GLY      4.2     8.7    -      -       -      +
    123H  LEU*     4.4    13.5    -      -       +      +
    124H  LEU*     3.7    18.6    -      -       +      -
    128H  SER*     4.6     2.7    -      -       -      +
    130H  GLU*     3.0    23.3    +      -       +      +
    131H  ASN*     3.5    19.7    -      -       -      +
    133H  ASP*     1.3    74.4    -      -       -      +
    135H  SER*     1.3    62.6    +      -       -      +
    137H  SER*     3.2     3.9    +      -       -      -
    138H  LEU*     3.2    27.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 135 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    170G  LEU      4.1     8.2    +      -       -      +
    173G  ASN*     2.7    27.8    +      -       -      +
    174G  LEU*     2.8    27.1    -      -       -      +
    124H  LEU*     4.5     8.2    -      -       -      +
    131H  ASN      2.8    11.4    +      -       -      -
    132H  ALA      3.3     9.0    -      -       -      -
    134H  ILE*     1.3    80.0    -      -       -      +
    136H  GLN*     1.3    63.4    +      -       -      +
    137H  SER      3.1     0.9    +      -       -      -
    138H  LEU*     3.3    15.2    +      -       -      +
    139H  LEU*     3.4    11.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 136 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132H  ALA      3.0    18.3    +      -       -      +
    133H  ASP*     4.2     7.9    +      -       -      +
    135H  SER*     1.3    73.9    -      -       -      +
    137H  SER*     1.3    62.1    +      -       -      +
    139H  LEU*     3.7    14.8    -      -       +      +
    140H  GLN*     3.1    45.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 137 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97H  ARG*     3.1    38.1    +      -       -      +
    100H  PHE*     4.5     5.7    -      -       -      +
    116H  PHE*     5.9     0.7    -      -       -      -
    133H  ASP      3.0    13.4    +      -       -      -
    134H  ILE*     3.3    10.8    -      -       -      -
    135H  SER      3.0     0.4    -      -       -      -
    136H  GLN*     1.3    75.1    -      -       -      +
    138H  LEU*     1.3    63.9    +      -       -      +
    140H  GLN*     3.1     8.5    +      -       -      +
    141H  THR*     2.6    42.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 138 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    170G  LEU*     3.9    15.0    -      -       +      +
    173G  ASN*     4.4    11.0    -      -       -      +
     92H  TYR*     3.9    18.8    -      -       +      -
    116H  PHE*     3.7    34.3    -      -       +      +
    117H  TYR*     3.5    17.5    -      -       +      +
    120H  GLY*     3.5     7.9    -      -       -      +
    121H  SER*     3.4    34.1    -      -       -      +
    124H  LEU*     5.3     0.7    -      -       +      -
    134H  ILE*     3.2    19.3    +      -       +      +
    135H  SER*     3.3     5.8    +      -       -      +
    137H  SER*     1.3    78.1    -      -       -      +
    139H  LEU*     1.3    63.5    +      -       -      +
    141H  THR*     3.5     4.9    +      -       -      -
    142H  PHE*     3.1    23.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 139 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    187E  ASP*     5.2     1.3    -      -       -      +
    139G  GLN*     4.3     8.5    -      -       -      +
    167G  MSE      4.4    17.9    -      -       +      +
    170G  LEU*     4.3    12.9    -      -       +      +
    171G  ARG*     4.0    58.6    -      -       +      +
    135H  SER      3.4     8.8    +      -       -      +
    136H  GLN*     3.7    17.9    -      -       +      +
    137H  SER      3.1     0.6    -      -       -      -
    138H  LEU*     1.3    76.7    -      -       -      +
    140H  GLN*     1.3    58.6    +      -       -      +
    142H  PHE*     2.9     4.9    +      -       -      +
    143H  ILE*     2.9    53.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 140 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    100H  PHE      5.7     0.7    -      -       -      +
    101H  SER*     3.7    33.7    +      -       -      +
    104H  PRO*     4.9     1.4    -      -       -      +
    136H  GLN*     3.1    42.5    +      -       +      +
    137H  SER*     3.6     5.9    -      -       -      +
    139H  LEU*     1.3    80.7    -      -       -      +
    141H  THR*     1.3    57.9    +      -       -      +
    143H  ILE*     3.4     9.1    +      -       -      +
    144H  GLY*     2.9    24.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 141 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    100H  PHE*     3.9    45.9    -      -       +      -
    104H  PRO*     3.9    14.9    -      -       -      +
    109H  LEU*     4.5     0.5    -      -       -      +
    116H  PHE*     4.3     9.3    -      -       +      -
    117H  TYR*     3.6    13.4    +      -       -      -
    137H  SER*     2.6    37.0    +      -       -      +
    138H  LEU*     3.9     8.1    -      -       -      +
    140H  GLN*     1.3    70.8    -      -       +      +
    142H  PHE*     1.3    64.8    +      -       -      +
    144H  GLY      3.5     0.7    +      -       -      -
    145H  ARG*     3.1    31.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 142 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    163G  ALA*     3.9     8.5    -      -       +      -
    166G  HIS*     4.0    24.5    -      +       +      -
    167G  MSE      3.3    38.6    -      -       +      -
    170G  LEU*     3.8    15.5    -      -       +      -
     13H  LEU*     5.1     0.7    -      -       +      -
    117H  TYR*     3.5    37.7    -      +       +      -
    138H  LEU      3.1    13.8    +      -       -      +
    139H  LEU*     2.9     9.2    +      -       -      +
    141H  THR*     1.3    75.8    +      -       -      +
    143H  ILE*     1.3    68.2    +      -       -      +
    145H  ARG*     3.1    10.2    +      -       -      +
    146H  PHE*     3.2    16.9    +      +       +      +
    171H  MSE      5.1     6.5    -      -       +      -
    172H  GLU*     4.6     9.6    -      -       +      -
    175H  LEU*     3.7    30.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 143 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    133G  ASP*     5.2     2.9    -      -       -      +
    136G  VAL*     3.4    24.2    -      -       +      +
    137G  ARG*     3.9    30.4    -      -       +      +
    139G  GLN*     5.8     5.4    -      -       +      +
    167G  MSE      3.3    39.7    -      -       +      -
    171G  ARG*     5.5     2.5    -      -       -      +
    139H  LEU*     2.9    33.6    +      -       +      +
    140H  GLN*     3.6     8.5    -      -       -      +
    142H  PHE*     1.3    77.3    -      -       -      +
    144H  GLY*     1.3    60.2    +      -       -      +
    145H  ARG      2.8     7.8    +      -       -      -
    146H  PHE*     2.9    19.4    +      -       -      +
    147H  ARG      4.5     1.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 144 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137G  ARG*     6.4     0.4    -      -       -      -
    104H  PRO*     3.7    18.6    -      -       -      +
    105H  ASN*     3.2    25.6    +      -       -      +
    140H  GLN      2.9    10.6    +      -       -      -
    141H  THR      3.5     0.4    +      -       -      -
    142H  PHE      3.3     0.4    -      -       -      -
    143H  ILE*     1.3    80.2    -      -       -      +
    145H  ARG*     1.3    61.3    +      -       -      +
    147H  ARG*     5.3     2.4    +      -       -      +
    148H  ARG      5.7     0.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 145 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    104H  PRO*     3.7    26.8    +      -       +      +
    105H  ASN*     3.7    16.5    +      -       -      +
    107H  VAL      3.4    16.7    +      -       -      -
    109H  LEU*     2.7    32.8    -      -       -      +
    117H  TYR*     3.8     3.4    -      -       -      -
    141H  THR*     3.1    23.8    -      -       -      +
    142H  PHE      3.1     3.9    +      -       -      +
    143H  ILE      2.8     3.0    +      -       -      -
    144H  GLY*     1.3    78.6    -      -       -      +
    146H  PHE*     1.3    66.1    +      -       -      +
    147H  ARG      3.5     1.8    -      -       -      -
    148H  ARG*     3.3     6.9    +      -       -      +
    149H  ILE*     2.9    31.4    +      -       +      +
    167H  ARG*     2.9    29.3    +      -       -      +
    168H  LEU*     3.9     8.6    -      -       -      +
    172H  GLU*     2.5    49.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 146 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132G  ALA*     3.8    11.0    -      -       +      -
    133G  ASP*     3.8    19.1    -      -       +      -
    136G  VAL*     3.4    36.8    -      -       +      -
    159G  PHE*     3.2    30.7    -      +       -      -
    160G  LEU*     3.7    14.8    -      -       +      -
    163G  ALA*     4.0    20.2    -      -       +      -
    167G  MSE      5.8     0.9    -      -       -      -
    142H  PHE*     3.2    18.8    +      +       +      +
    143H  ILE*     2.9    15.7    +      -       -      +
    145H  ARG*     1.3    75.9    -      -       -      +
    147H  ARG*     1.3    65.9    +      -       -      +
    149H  ILE*     3.0     8.7    +      -       +      +
    150H  MSE      2.9    49.5    +      -       +      +
    175H  LEU*     5.5     2.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 147 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    129G  ARG*     4.1     6.8    -      -       -      +
    130G  VAL*     3.2    44.5    -      -       -      +
    133G  ASP*     3.2    45.8    +      -       +      +
    137G  ARG*     5.6     0.4    -      -       -      +
    143H  ILE      4.5     1.2    +      -       -      -
    144H  GLY      5.3     2.2    +      -       -      +
    145H  ARG      3.5     0.6    -      -       -      -
    146H  PHE*     1.3    83.6    -      -       -      +
    148H  ARG*     1.3    60.5    +      -       -      +
    150H  MSE      3.6     6.5    +      -       -      +
    151H  ASP*     2.9    68.8    +      -       -      +
     69K  GLU*     5.0     5.8    +      -       -      -
     73K  LYS*     4.9    14.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 148 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105H  ASN*     3.4    49.1    +      -       -      +
    144H  GLY      5.7     0.2    +      -       -      -
    145H  ARG*     3.3     4.2    +      -       +      +
    146H  PHE      3.2     0.8    -      -       -      -
    147H  ARG*     1.3    78.1    -      -       -      +
    149H  ILE*     1.3    66.8    +      -       +      +
    151H  ASP*     4.4     5.5    -      -       +      +
    152H  SER*     3.5    21.5    +      -       -      -
    164H  LEU*     3.8    26.8    -      -       +      +
     67K  ASP*     3.2    26.8    +      -       -      -
     69K  GLU*     3.5    39.7    +      -       -      +
     70K  LYS*     4.9    10.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 149 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    159G  PHE*     4.2    19.3    -      -       +      -
    145H  ARG*     2.9    31.6    +      -       +      +
    146H  PHE*     3.0     8.8    +      -       -      +
    148H  ARG*     1.3    79.0    -      -       +      +
    150H  MSE      1.3    58.6    +      -       -      +
    152H  SER*     3.9     1.6    -      -       -      -
    153H  SER*     3.0    28.1    +      -       -      -
    164H  LEU*     4.8     6.3    -      -       +      -
    168H  LEU*     3.1    38.1    -      -       +      -
    172H  GLU*     4.1    35.2    -      -       +      +
    175H  LEU*     4.3    11.7    -      -       +      -
    176H  PHE*     4.0    11.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with MSE 150 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128G  LEU*     6.1     1.6    -      -       +      -
    129G  ARG*     3.6    43.7    -      -       +      +
    132G  ALA*     4.0    13.5    -      -       +      -
    133G  ASP*     5.8     0.4    -      -       -      -
    156G  SER*     5.2     5.2    -      -       -      -
    159G  PHE*     3.6    30.3    -      -       +      -
    160G  LEU*     4.6     8.5    -      -       +      -
    146H  PHE*     2.9    44.8    +      -       +      +
    147H  ARG*     3.8     7.2    -      -       -      +
    149H  ILE*     1.3    77.4    -      -       -      +
    151H  ASP*     1.3    69.5    +      -       -      +
    153H  SER*     3.2     2.1    +      -       -      -
    154H  GLN*     2.9    53.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 151 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    129G  ARG*     3.7    27.1    -      -       -      +
    147H  ARG*     2.9    50.0    +      -       -      +
    148H  ARG*     4.4     5.5    -      -       +      +
    149H  ILE      3.6     0.2    -      -       -      -
    150H  MSE      1.3    77.6    -      -       -      +
    152H  SER*     1.3    58.4    +      -       -      +
    154H  GLN      3.8     0.9    -      -       -      -
    155H  ASN*     2.7    41.7    +      -       -      +
     69K  GLU*     4.0    14.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 152 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    148H  ARG      3.5     9.4    +      -       -      -
    149H  ILE      3.9     0.4    -      -       -      -
    150H  MSE      3.1     0.4    -      -       -      -
    151H  ASP*     1.3    78.4    -      -       -      +
    153H  SER*     1.3    65.9    +      -       -      +
    155H  ASN*     3.3    19.1    +      -       -      +
    156H  ALA      5.4     0.7    -      -       -      +
    157H  TYR*     6.0     0.5    -      -       -      -
    161H  THR*     3.8    21.0    +      -       -      +
    164H  LEU*     3.2    33.1    -      -       -      +
    176H  PHE*     3.2    17.9    -      -       -      -
    180H  GLN*     4.4     0.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 153 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    159G  PHE*     3.6    10.4    -      -       -      -
    149H  ILE      3.0    16.9    +      -       -      -
    150H  MSE      3.2     8.1    +      -       -      -
    152H  SER*     1.3    76.1    -      -       -      +
    154H  GLN*     1.3    62.9    +      -       -      +
    155H  ASN      3.3     3.8    +      -       -      +
    176H  PHE*     3.2    47.9    -      -       -      -
    179H  GLY*     3.4    19.0    -      -       -      +
    180H  GLN*     2.8    29.6    -      -       -      +
    183H  LEU*     4.5     1.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 154 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125G  ILE*     3.7     6.6    -      -       +      +
    129G  ARG*     3.4    41.5    +      -       -      +
    155G  THR      5.3     4.7    -      -       -      +
    156G  SER*     3.3    29.8    +      -       -      +
    159G  PHE*     3.9    16.7    -      -       +      +
    150H  MSE      2.9    48.6    +      -       -      +
    151H  ASP      3.8     1.8    -      -       -      +
    153H  SER*     1.3    84.8    +      -       -      +
    155H  ASN*     1.3    58.3    +      -       -      +
    179H  GLY*     4.4    12.8    -      -       -      +
    183H  LEU*     3.8    21.4    -      -       +      +
----------------------------------------------------------
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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