Contacts of the helix formed by residues 72 - 94 (chain H) in PDB entry 1P7G


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 ASP 72 (chain H).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60G  LYS*     5.1     7.3    +      -       -      -
     72G  ASP*     5.4     2.6    -      -       -      +
     75G  ALA*     4.2     7.6    -      -       -      +
     79G  ASP*     4.5     3.3    -      -       -      +
     71H  ILE*     1.3    74.9    -      -       -      +
     73H  ILE*     1.3    57.7    +      -       -      +
     74H  ARG*     3.7     4.9    +      -       -      +
     75H  ALA*     2.9    22.5    +      -       +      +
     76H  VAL*     2.8    29.2    +      -       +      +
    408H  BME      2.9    24.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 73 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128E  GLU*     4.1    18.4    -      -       +      +
    131E  GLN*     3.6    32.3    -      -       +      +
    132E  ALA*     4.1    14.1    -      -       +      +
    135E  ASN*     3.7    19.1    -      -       +      +
     61H  LEU*     3.8    25.1    -      -       +      -
     71H  ILE*     3.2    25.3    +      -       +      +
     72H  ASP*     1.3    73.1    -      -       -      +
     74H  ARG*     1.3    61.8    +      -       -      +
     76H  VAL*     4.5     0.2    -      -       -      -
     77H  LEU*     2.9    63.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 74 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135E  ASN*     3.0    36.9    +      -       +      +
    136E  VAL      4.4     0.4    +      -       -      -
    137E  GLU*     3.6    29.1    +      -       -      +
    157E  GLN*     3.2    31.4    +      -       -      +
    159E  GLU*     5.0     0.2    -      -       -      -
     79G  ASP*     2.7    28.8    +      -       -      +
     83G  HIS*     5.0    10.5    -      -       -      -
     72H  ASP*     3.1     3.7    +      -       -      +
     73H  ILE*     1.3    81.6    -      -       -      +
     75H  ALA*     1.3    59.4    +      -       -      +
     78H  ARG*     2.8    65.0    +      -       -      +
    408H  BME      3.3    20.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 75 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72G  ASP*     4.1     9.6    -      -       -      +
     75G  ALA*     3.7    11.0    -      -       +      -
     72H  ASP*     2.9    32.3    +      -       +      +
     74H  ARG*     1.3    80.2    -      -       -      +
     76H  VAL*     1.3    64.5    +      -       +      +
     78H  ARG*     3.6     2.1    -      -       -      +
     79H  ASP*     3.0    31.0    +      -       -      +
    408H  BME      3.2    27.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 76 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57H  ALA*     3.9    17.6    -      -       +      +
     60H  LYS*     4.2    22.4    -      -       +      +
     61H  LEU*     3.6    35.9    -      -       +      -
     71H  ILE*     3.3    33.2    -      -       +      -
     72H  ASP*     2.8    20.3    +      -       +      +
     73H  ILE      4.0     2.2    -      -       -      +
     75H  ALA*     1.3    73.9    -      -       +      +
     77H  LEU*     1.3    58.6    +      -       -      +
     79H  ASP*     3.1    10.1    +      -       -      +
     80H  LEU*     2.8    26.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 77 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128E  GLU*     5.1     2.0    -      -       -      +
    132E  ALA*     3.8    11.7    -      -       +      -
    155E  ILE*     3.2    30.3    -      -       +      +
    156E  LEU*     4.2     4.1    -      -       +      +
    157E  GLN*     3.8    40.6    -      -       +      +
    164E  MSE      5.3     0.9    -      -       -      -
     61H  LEU*     4.2    22.4    -      -       +      -
     73H  ILE*     2.9    52.7    +      -       +      +
     74H  ARG      4.1     1.3    -      -       -      +
     76H  VAL*     1.3    71.3    -      -       -      +
     78H  ARG*     1.3    60.3    +      -       -      +
     80H  LEU*     3.6     8.7    -      -       +      +
     81H  SER*     2.8    31.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 78 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137E  GLU*     2.8    38.4    +      -       -      +
    157E  GLN*     4.8     1.3    -      -       -      +
    159E  GLU*     3.1    28.4    +      -       -      -
    164E  MSE      3.5    28.6    -      -       +      +
    137F  GLU*     4.5     4.5    -      -       -      +
     78G  ARG*     3.5    46.1    -      -       -      +
     79G  ASP*     4.6     0.8    +      -       -      -
    160G  LYS*     3.8     6.3    -      -       -      +
     74H  ARG*     2.8    32.4    +      -       +      +
     75H  ALA      3.6     4.5    -      -       -      +
     77H  LEU*     1.3    75.8    -      -       -      +
     79H  ASP*     1.3    64.0    +      -       -      +
     81H  SER*     3.3     3.1    +      -       -      -
     82H  PHE*     3.1    23.0    +      -       -      +
    162H  ASN*     4.3     2.4    +      -       -      -
    408H  BME      3.2    31.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 79 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137F  GLU*     4.0     8.6    -      -       -      +
     72G  ASP*     4.6     9.0    -      -       -      +
     74G  ARG*     2.9    35.6    +      -       -      -
     78G  ARG*     4.7     3.8    +      -       -      -
     53H  GLY      5.5     0.7    -      -       -      +
     57H  ALA*     4.7     7.4    -      -       +      -
     60H  LYS*     4.5    14.9    +      -       -      +
     75H  ALA*     3.0    22.6    +      -       -      +
     76H  VAL*     3.1     9.8    +      -       -      +
     78H  ARG*     1.3    74.4    -      -       -      +
     80H  LEU*     1.3    66.9    +      -       -      +
     82H  PHE*     3.2     3.1    +      -       -      +
     83H  HIS*     2.9    38.3    +      -       +      +
    408H  BME      5.8     1.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 80 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    154E  LEU*     3.9    33.2    -      -       +      -
    155E  ILE      4.6     1.6    -      -       -      +
    156E  LEU*     4.3    15.0    -      -       +      -
     54H  ALA*     4.4     4.7    -      -       +      +
     57H  ALA*     3.9    16.1    -      -       +      +
     58H  LEU*     3.3    31.0    -      -       +      -
     61H  LEU*     3.9    23.1    -      -       +      -
     76H  VAL      2.8    19.2    +      -       -      +
     77H  LEU*     3.2    13.0    +      -       +      +
     79H  ASP*     1.3    71.7    -      -       -      +
     81H  SER*     1.3    58.6    +      -       -      +
     83H  HIS*     4.8     1.6    -      -       -      -
     84H  LEU*     2.8    51.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 81 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    156E  LEU*     4.9    10.3    -      -       -      +
    157E  GLN      5.6     0.9    -      -       -      -
    164E  MSE      2.9    40.5    +      -       -      +
    166E  ALA*     6.5     0.7    -      -       -      +
     77H  LEU      2.8    17.5    +      -       -      -
     78H  ARG      3.4     5.8    -      -       -      -
     80H  LEU*     1.3    79.7    -      -       -      +
     82H  PHE*     1.3    62.8    +      -       -      +
     84H  LEU*     4.4     2.5    -      -       -      +
     85H  ASN*     3.2    28.0    +      -       -      +
    162H  ASN*     3.0    20.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 82 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137F  GLU*     3.3    53.8    -      -       +      +
    138F  GLY      4.5     3.8    -      -       -      -
     50H  TYR*     4.2    13.2    -      +       -      -
     78H  ARG      3.1     6.3    +      -       -      +
     79H  ASP      3.6     5.2    -      -       -      +
     81H  SER*     1.3    78.6    -      -       -      +
     83H  HIS*     1.3    85.1    +      +       -      +
     86H  GLY      3.0    21.0    +      -       -      -
    160H  LYS*     3.9    12.8    -      -       +      -
    161H  HIS*     3.7    21.7    +      +       -      +
    162H  ASN*     3.4    23.0    -      -       -      +
    178H  TRP*     3.5    40.4    -      +       -      -
----------------------------------------------------------
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Residues in contact with HIS 83 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74G  ARG*     5.0    11.2    -      -       -      -
     49H  GLY      4.2     3.2    +      -       -      -
     50H  TYR*     3.4    38.2    -      +       -      +
     53H  GLY*     3.2    32.5    +      -       -      -
     54H  ALA*     3.4    19.5    -      -       -      +
     79H  ASP*     2.9    29.7    +      -       +      +
     80H  LEU      4.1     0.2    -      -       -      +
     82H  PHE*     1.3    95.3    -      +       -      +
     84H  LEU*     1.3    65.9    +      -       -      +
     85H  ASN      3.1     1.6    -      -       -      -
     86H  GLY      3.2     0.7    +      -       -      +
     87H  HIS*     3.0    23.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 84 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    147E  GLU*     3.8    13.2    -      -       +      +
    154E  LEU*     3.5    32.1    -      -       +      -
    156E  LEU*     5.6     2.9    -      -       +      -
    166E  ALA*     4.5    17.3    -      -       +      -
     18H  TYR*     3.5    42.2    -      -       +      +
     54H  ALA*     4.2     6.7    -      -       +      +
     80H  LEU*     2.8    33.0    +      -       +      +
     81H  SER*     4.4     2.0    -      -       -      +
     83H  HIS*     1.3    73.5    -      -       -      +
     85H  ASN*     1.3    57.7    +      -       -      +
     87H  HIS*     3.3     7.5    +      -       +      +
     88H  ILE*     2.9    50.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 85 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    165E  HIS      2.6    22.9    -      -       -      +
    166E  ALA*     3.7     5.2    -      -       -      +
    167E  ALA*     2.8    40.8    -      -       -      +
     81H  SER*     3.2    15.5    +      -       -      +
     82H  PHE      3.9     1.3    -      -       -      +
     83H  HIS      3.1     0.4    -      -       -      -
     84H  LEU*     1.3    76.8    -      -       -      +
     86H  GLY*     1.3    65.4    +      -       -      +
     87H  HIS      3.0     1.1    -      -       -      -
     88H  ILE*     4.2     6.7    -      -       -      +
     89H  LEU*     3.0    30.0    +      -       -      +
    161H  HIS*     3.2    26.0    -      -       -      +
    162H  ASN*     3.0    18.9    -      -       -      +
    165H  HIS*     3.3     2.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 86 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50H  TYR*     3.7    13.9    -      -       -      -
     82H  PHE      3.0    12.4    +      -       -      -
     83H  HIS      3.2     3.9    +      -       -      -
     85H  ASN*     1.3    75.3    -      -       -      +
     87H  HIS*     1.3    56.4    +      -       -      +
     89H  LEU*     4.1     0.6    -      -       -      +
     90H  HIS*     2.6    36.7    +      -       -      +
    161H  HIS*     3.2    31.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 87 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    149E  LEU*     3.3    23.9    -      -       +      +
    150E  GLU*     5.8     0.4    +      -       -      -
     18H  TYR*     3.2    40.2    -      +       +      +
     19H  THR      3.1    27.2    +      -       -      -
     21H  PRO*     3.9     7.4    -      -       +      -
     47H  HIS*     3.3    16.0    +      -       -      -
     50H  TYR*     3.9    11.8    -      -       +      +
     51H  VAL*     3.9    10.4    -      -       +      +
     54H  ALA*     5.6     1.6    -      -       +      -
     83H  HIS      3.0    11.9    +      -       -      +
     84H  LEU*     3.4    11.9    -      -       +      +
     85H  ASN      3.0     0.2    -      -       -      -
     86H  GLY*     1.3    75.3    -      -       -      +
     88H  ILE*     1.3    55.1    +      -       -      +
     90H  HIS*     3.1     1.4    +      -       -      -
     91H  SER*     2.7    57.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 88 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    147E  GLU*     4.3    13.2    -      -       +      +
    149E  LEU*     4.2    16.6    -      -       +      -
    166E  ALA*     4.9     3.1    -      -       +      -
    167E  ALA*     3.4    37.9    -      -       +      +
    168E  ASP*     4.7     5.4    -      -       -      +
     84H  LEU*     2.9    49.0    +      -       +      +
     85H  ASN*     4.1    13.2    -      -       -      +
     87H  HIS*     1.3    70.7    -      -       -      +
     89H  LEU*     1.3    64.4    +      -       -      +
     91H  SER*     3.0    16.9    +      -       -      -
     92H  ILE*     3.1    36.5    +      -       +      +
    220H  LEU*     4.7    11.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 89 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    167E  ALA*     4.1    12.3    -      -       +      -
     85H  ASN      3.0    17.4    +      -       -      +
     86H  GLY      4.3     0.2    -      -       -      +
     88H  ILE*     1.3    75.7    -      -       -      +
     90H  HIS*     1.3    58.0    +      -       -      +
     92H  ILE*     3.2     7.9    +      -       +      +
     93H  PHE*     2.8    28.2    +      -       -      +
    141H  TRP*     3.5    51.2    -      -       +      +
    143H  ILE*     4.6    15.3    -      -       +      -
    158H  ILE*     4.8     0.2    -      -       +      -
    161H  HIS*     3.3    27.1    -      -       +      +
    165H  HIS*     3.8    24.2    -      -       +      -
    171H  VAL*     4.6    13.5    -      -       +      -
    174H  ALA*     4.8     4.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 90 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42H  HIS*     2.9    40.9    +      +       -      -
     47H  HIS*     3.2    36.6    -      +       +      +
     50H  TYR*     3.3    27.3    -      +       -      -
     86H  GLY      2.6    28.1    +      -       -      +
     87H  HIS      3.1     1.4    +      -       -      -
     89H  LEU*     1.3    72.5    -      -       -      +
     91H  SER*     1.3    59.2    +      -       -      +
     92H  ILE      2.9    10.6    +      -       -      -
     93H  PHE*     3.2    12.2    +      +       -      -
     94H  TRP*     3.2    37.6    +      +       -      -
    141H  TRP*     3.4    24.7    -      +       -      -
    161H  HIS*     4.2     5.6    -      -       -      -
    176H  ASP*     3.8     2.7    +      -       -      -
    180H  HIS*     4.4     1.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 91 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    149E  LEU*     4.3     6.5    -      -       -      +
     21H  PRO*     3.7    15.3    -      -       -      +
     47H  HIS*     3.7     5.5    +      -       -      -
     87H  HIS*     2.7    49.4    +      -       -      -
     88H  ILE*     3.0     9.8    +      -       -      -
     90H  HIS*     1.3    71.9    -      -       -      +
     92H  ILE*     1.3    55.2    +      -       -      +
     94H  TRP*     4.9     2.2    -      -       -      -
     95H  PRO*     3.5    11.1    -      -       -      +
    220H  LEU*     5.8     0.9    -      -       -      -
    308H  ACT      2.6    42.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 92 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168E  ASP*     4.2     8.5    -      -       -      +
     88H  ILE*     3.1    34.5    +      -       +      +
     89H  LEU*     3.7     8.3    -      -       +      +
     90H  HIS      2.9     0.6    -      -       -      -
     91H  SER*     1.3    84.0    -      -       -      +
     93H  PHE*     1.3    60.6    +      -       -      +
     94H  TRP      3.3     1.6    -      -       -      -
     95H  PRO*     3.4     6.0    -      -       -      +
     96H  ASN*     2.8    47.9    +      -       -      +
    171H  VAL*     4.3    29.8    -      -       +      +
    172H  LEU      4.8     0.7    -      -       -      +
    174H  ALA*     5.0     2.9    -      -       +      -
    209H  ARG*     3.7    26.0    -      -       -      +
    219H  ALA      5.5     0.2    -      -       -      +
    220H  LEU*     4.0    22.4    -      -       +      -
    308H  ACT      4.0     1.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 93 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34H  ILE*     5.1     3.8    -      -       +      -
     39H  MSE      5.3     2.2    -      -       +      -
     42H  HIS*     4.5    12.3    -      +       -      -
     89H  LEU      2.8    17.0    +      -       -      +
     90H  HIS*     3.2     6.5    +      +       -      +
     92H  ILE*     1.3    78.8    -      -       -      +
     94H  TRP*     1.3    94.9    +      +       -      +
     96H  ASN*     3.4    16.7    +      -       -      +
     97H  MSE      3.4    37.0    -      -       +      +
    141H  TRP*     3.7    18.6    -      +       +      -
    174H  ALA*     3.1    26.2    -      -       -      +
    175H  LEU*     4.0     1.1    -      -       +      -
    176H  ASP*     3.4    31.0    -      -       +      -
    181H  ALA*     5.4     0.9    -      -       +      -
    193H  TYR*     4.0    15.0    -      -       -      -
    197H  TRP*     4.0    17.9    -      +       -      -
----------------------------------------------------------
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Residues in contact with TRP 94 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21H  PRO*     4.8     5.6    -      -       +      -
     22H  PRO      5.2     1.6    -      -       -      -
     23H  LEU*     4.5     8.3    -      -       +      -
     24H  PRO*     4.2     9.0    -      -       +      -
     25H  TYR*     2.9    49.6    +      -       +      +
     39H  MSE      3.7    22.7    -      -       +      -
     42H  HIS*     3.2    41.3    -      +       +      -
     43H  HIS*     3.2    38.8    -      +       +      -
     47H  HIS*     2.7    29.6    +      +       -      -
     90H  HIS*     3.2    27.6    +      +       -      -
     91H  SER*     4.9     2.5    -      -       -      -
     93H  PHE*     1.3    99.0    -      +       -      +
     95H  PRO*     1.3    65.1    -      -       +      +
     96H  ASN      3.0     4.3    -      -       -      -
     97H  MSE      3.0    17.1    +      -       +      +
----------------------------------------------------------
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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