Contacts of the helix formed by residues 72 - 94 (chain D) 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 D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60C  LYS*     4.9     8.2    +      -       -      -
     72C  ASP*     5.7     1.0    -      -       -      +
     75C  ALA*     4.0     7.4    -      -       -      +
     76C  VAL*     6.0     1.2    -      -       -      +
     79C  ASP*     4.6     4.5    -      -       -      +
     71D  ILE*     1.3    72.0    -      -       -      +
     73D  ILE*     1.3    63.3    +      -       -      +
     74D  ARG*     3.6     4.5    +      -       -      +
     75D  ALA*     3.2    24.2    +      -       +      +
     76D  VAL*     3.0    25.8    +      -       +      +
    404D  BME      3.1    28.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 73 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128A  GLU*     4.3    17.0    -      -       +      +
    131A  GLN*     3.7    31.0    -      -       +      +
    132A  ALA*     4.0    16.4    -      -       +      +
    135A  ASN*     4.0    17.3    -      -       +      +
    157A  GLN*     4.2     0.7    -      -       -      +
     61D  LEU*     4.1    18.6    -      -       +      -
     64D  PHE*     5.7     0.4    -      -       +      -
     71D  ILE*     3.4    24.5    +      -       +      +
     72D  ASP*     1.3    73.8    +      -       -      +
     74D  ARG*     1.3    60.0    +      -       -      +
     76D  VAL      4.7     0.2    -      -       -      +
     77D  LEU*     2.9    70.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 74 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135A  ASN*     3.0    47.7    +      -       +      +
    136A  VAL      4.8     0.2    +      -       -      -
    137A  GLU*     3.8    29.1    +      -       -      +
    157A  GLN*     3.1    28.9    +      -       -      +
    159A  GLU*     5.0     0.4    -      -       -      -
     79C  ASP*     3.3    24.6    +      -       -      +
     83C  HIS*     5.1    11.1    -      -       -      -
     72D  ASP*     3.3     2.4    +      -       -      +
     73D  ILE*     1.3    81.4    -      -       +      +
     75D  ALA*     1.3    59.8    +      -       -      +
     77D  LEU*     3.8     0.7    -      -       -      +
     78D  ARG*     2.8    75.9    +      -       -      +
    404D  BME      3.0    19.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 75 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72C  ASP*     3.9     8.7    -      -       -      +
     75C  ALA*     3.7    15.0    -      -       +      -
     72D  ASP*     3.2    31.9    +      -       +      +
     74D  ARG*     1.3    80.8    -      -       -      +
     76D  VAL*     1.3    59.0    +      -       +      +
     78D  ARG*     3.4     1.9    +      -       -      +
     79D  ASP*     2.9    36.1    +      -       -      +
    404D  BME      3.4    22.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 76 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57D  ALA*     3.6    34.5    -      -       +      +
     60D  LYS*     3.7    24.2    -      -       +      -
     61D  LEU*     4.0    19.5    -      -       +      -
     71D  ILE*     3.6    24.5    -      -       +      -
     72D  ASP*     3.0    19.5    +      -       +      +
     73D  ILE*     4.3     1.6    -      -       +      +
     75D  ALA*     1.3    74.9    -      -       +      +
     77D  LEU*     1.3    57.0    +      -       -      +
     79D  ASP*     3.2     8.7    +      -       +      +
     80D  LEU*     2.7    33.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 77 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128A  GLU*     5.0     1.8    -      -       -      +
    132A  ALA*     3.7    20.0    -      -       +      -
    155A  ILE*     3.3    30.7    -      -       +      +
    156A  LEU*     4.2     6.0    -      -       +      +
    157A  GLN*     3.8    28.5    -      -       +      +
    164A  MSE      4.3     3.6    -      -       -      +
     61D  LEU*     4.4    22.2    -      -       +      -
     73D  ILE*     2.9    49.5    +      -       +      +
     74D  ARG      4.0     1.6    -      -       -      +
     76D  VAL*     1.3    74.6    -      -       -      +
     78D  ARG*     1.3    65.1    +      -       -      +
     80D  LEU*     4.0     8.0    -      -       +      +
     81D  SER*     3.0    25.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 78 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137A  GLU*     2.7    33.7    +      -       -      +
    157A  GLN*     4.8     2.2    -      -       -      +
    159A  GLU*     3.0    26.3    +      -       -      -
    164A  MSE      3.6    30.3    -      -       +      -
    137B  GLU*     4.4     4.8    -      -       -      +
     78C  ARG*     3.8    36.1    -      -       -      +
     79C  ASP*     4.4     0.8    +      -       -      -
    160C  LYS*     3.5     4.2    -      -       -      +
     74D  ARG*     2.8    36.1    +      -       -      +
     75D  ALA      3.6     4.0    -      -       -      +
     77D  LEU*     1.3    81.0    -      -       -      +
     79D  ASP*     1.3    62.3    +      -       -      +
     81D  SER*     3.5     2.3    +      -       -      -
     82D  PHE*     3.2    22.7    +      -       -      +
    162D  ASN*     4.3     3.1    +      -       -      -
    404D  BME      3.1    41.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 79 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137B  GLU*     4.5     3.9    -      -       -      +
     72C  ASP*     4.6    10.1    -      -       -      +
     74C  ARG*     2.9    34.5    +      -       -      +
     78C  ARG*     4.7     3.1    +      -       -      -
     57D  ALA*     4.5     9.6    -      -       +      -
     60D  LYS*     4.8    11.3    +      -       -      -
     75D  ALA*     2.9    26.9    +      -       -      +
     76D  VAL*     3.4    11.8    -      -       -      +
     78D  ARG*     1.3    76.9    -      -       -      +
     80D  LEU*     1.3    63.1    +      -       -      +
     82D  PHE*     3.1     7.9    +      -       -      +
     83D  HIS*     3.1    36.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 80 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    154A  LEU*     4.0    23.3    -      -       +      -
    155A  ILE      4.9     1.8    -      -       -      +
    156A  LEU*     4.7     9.2    -      -       +      -
     18D  TYR*     5.8     0.9    -      -       +      -
     54D  ALA*     3.9    18.8    -      -       +      +
     57D  ALA*     3.8    11.2    -      -       +      +
     58D  LEU*     3.9    19.1    -      -       +      -
     61D  LEU*     3.6    27.6    -      -       +      -
     76D  VAL      2.7    20.2    +      -       -      +
     77D  LEU*     4.0    13.7    -      -       +      +
     79D  ASP*     1.3    72.2    -      -       -      +
     81D  SER*     1.3    58.3    +      -       -      +
     83D  HIS*     5.1     1.6    -      -       -      -
     84D  LEU*     2.8    57.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 81 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    156A  LEU*     4.6    11.1    -      -       -      +
    164A  MSE      2.9    47.0    +      -       -      +
    165A  HIS      4.7     0.2    -      -       -      -
    166A  ALA*     6.4     1.1    -      -       -      +
     77D  LEU      3.0    20.1    +      -       -      -
     78D  ARG      3.7     4.3    -      -       -      -
     79D  ASP      3.3     0.2    -      -       -      -
     80D  LEU*     1.3    76.4    -      -       -      +
     82D  PHE*     1.3    63.1    +      -       -      +
     84D  LEU*     4.2     3.3    -      -       -      +
     85D  ASN*     2.7    34.2    +      -       -      +
    162D  ASN*     3.4    10.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 82 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137B  GLU*     3.2    52.0    -      -       +      +
    138B  GLY      4.6     3.4    -      -       -      -
     50D  TYR*     3.7    23.3    -      +       -      -
     78D  ARG      3.2     6.7    +      -       -      +
     79D  ASP      3.1     7.9    +      -       -      +
     81D  SER*     1.3    81.4    -      -       -      +
     83D  HIS*     1.3    81.2    +      +       -      +
     86D  GLY*     3.0    23.0    +      -       -      -
    160D  LYS*     4.2     8.3    -      -       +      -
    161D  HIS*     3.5    31.1    +      -       +      +
    162D  ASN*     3.5    21.0    -      -       -      +
    178D  TRP*     3.8    26.2    -      +       -      -
----------------------------------------------------------
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Residues in contact with HIS 83 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137B  GLU*     5.6     0.2    -      -       -      -
     74C  ARG*     5.2    11.7    -      -       -      -
     49D  GLY      3.9     3.1    +      -       -      -
     50D  TYR*     3.4    36.0    -      +       -      +
     53D  GLY*     3.1    34.3    +      -       -      -
     54D  ALA*     3.1    21.3    -      -       -      +
     79D  ASP*     3.1    23.0    +      -       +      +
     82D  PHE*     1.3    99.7    -      +       -      +
     84D  LEU*     1.3    67.2    +      -       -      +
     86D  GLY*     3.0     2.0    +      -       -      +
     87D  HIS*     2.9    22.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 84 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    147A  GLU*     4.1     8.3    -      -       +      -
    154A  LEU*     3.5    31.9    -      -       +      -
    156A  LEU*     5.6     4.0    -      -       +      -
    166A  ALA*     4.3    17.9    -      -       +      -
     18D  TYR*     3.7    39.7    -      -       +      +
     54D  ALA*     4.0     7.9    -      -       +      +
     80D  LEU*     2.8    35.8    +      -       +      +
     81D  SER*     4.2     3.6    -      -       -      +
     83D  HIS*     1.3    72.7    -      -       -      +
     85D  ASN*     1.3    58.3    +      -       -      +
     87D  HIS*     3.0     7.2    +      -       +      +
     88D  ILE*     2.9    50.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 85 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    165A  HIS      3.0    17.1    -      -       -      +
    166A  ALA*     3.7     4.8    -      -       -      +
    167A  ALA*     2.8    36.5    -      -       -      +
     81D  SER*     2.7    26.3    +      -       -      +
     84D  LEU*     1.3    76.3    -      -       -      +
     86D  GLY*     1.3    66.9    +      -       -      +
     88D  ILE*     4.4     4.8    -      -       -      +
     89D  LEU*     2.9    29.5    +      -       -      +
    161D  HIS*     3.1    28.9    -      -       +      +
    162D  ASN*     3.3     8.1    -      -       -      +
    165D  HIS*     3.3    17.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 86 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50D  TYR*     4.0    10.9    -      -       -      -
     82D  PHE      3.0    11.8    +      -       -      -
     83D  HIS      3.0     4.2    +      -       -      -
     85D  ASN*     1.3    75.7    -      -       -      +
     87D  HIS*     1.3    60.9    +      -       -      +
     90D  HIS*     2.8    32.8    +      -       -      +
    161D  HIS*     3.5    34.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 87 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    149A  LEU*     3.7    18.3    -      -       +      +
    150A  GLU*     5.4     1.6    +      -       -      -
     18D  TYR*     3.3    42.6    -      +       +      +
     19D  THR      3.2    27.6    +      -       -      -
     21D  PRO*     3.6     7.9    -      -       +      -
     47D  HIS*     2.9    28.1    +      -       -      -
     50D  TYR*     3.8     7.5    -      -       +      +
     51D  VAL*     3.4    17.6    -      -       +      +
     54D  ALA*     5.4     1.3    -      -       +      -
     83D  HIS      2.9    12.3    +      -       -      +
     84D  LEU*     3.3    11.2    -      -       +      +
     86D  GLY*     1.3    74.5    -      -       -      +
     88D  ILE*     1.3    64.5    +      -       -      +
     90D  HIS      3.4     0.7    +      -       -      -
     91D  SER*     2.8    43.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 88 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    147A  GLU*     4.0    14.4    -      -       -      +
    149A  LEU*     4.3    17.9    -      -       +      -
    166A  ALA*     4.9     2.9    -      -       +      -
    167A  ALA*     3.5    41.7    -      -       +      +
    168A  ASP*     4.4     6.5    -      -       +      +
    169A  ALA*     6.3     0.2    -      -       +      -
     84D  LEU*     2.9    48.9    +      -       +      +
     85D  ASN*     4.0     5.4    -      -       -      +
     87D  HIS*     1.3    71.6    -      -       -      +
     89D  LEU*     1.3    64.5    +      -       -      +
     91D  SER*     3.1     9.0    +      -       -      -
     92D  ILE*     3.1    39.3    +      -       +      +
    220D  LEU*     4.8     9.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 89 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    167A  ALA*     4.3    11.2    -      -       +      -
     85D  ASN      2.9    21.7    +      -       -      +
     86D  GLY      4.3     0.2    -      -       -      +
     88D  ILE*     1.3    74.3    -      -       -      +
     90D  HIS*     1.3    57.5    +      -       -      +
     92D  ILE*     3.4     6.7    +      -       +      +
     93D  PHE*     2.8    29.5    +      -       -      +
    141D  TRP*     3.5    50.2    -      -       +      +
    143D  ILE*     4.6     9.6    -      -       +      -
    158D  ILE*     4.5     0.9    -      -       +      -
    161D  HIS*     3.4    26.2    -      -       -      +
    165D  HIS*     3.7    26.5    -      -       +      +
    171D  VAL*     4.5    20.6    -      -       +      -
    174D  ALA*     4.4     4.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 90 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42D  HIS*     2.6    42.2    +      +       -      -
     47D  HIS*     3.4    27.6    -      +       +      +
     50D  TYR*     3.6    25.9    -      +       -      -
     86D  GLY      2.8    28.1    +      -       -      +
     89D  LEU*     1.3    75.7    -      -       -      +
     91D  SER*     1.3    61.3    +      -       -      +
     93D  PHE*     3.4     6.5    -      +       -      +
     94D  TRP*     2.9    50.3    +      +       -      +
    141D  TRP*     3.6    23.5    -      +       -      -
    161D  HIS*     3.8     8.1    -      -       -      -
    176D  ASP*     3.2     6.2    +      -       -      -
    180D  HIS*     4.7     2.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with SER 91 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    149A  LEU*     4.8     7.0    -      -       -      +
     21D  PRO*     3.6    16.5    -      -       -      +
     47D  HIS*     3.7     4.2    -      -       -      -
     87D  HIS*     2.8    42.3    +      -       -      -
     88D  ILE*     3.1     8.4    +      -       -      -
     90D  HIS*     1.3    77.3    -      -       -      +
     92D  ILE*     1.3    56.6    +      -       -      +
     94D  TRP*     4.2     4.0    -      -       -      -
     95D  PRO*     2.9    24.8    -      -       -      +
    304D  ACT      3.3    23.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 92 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168A  ASP*     3.8    23.1    -      -       -      +
     88D  ILE*     3.1    25.6    +      -       +      +
     89D  LEU*     3.8     9.6    -      -       +      +
     91D  SER*     1.3    76.4    -      -       -      +
     93D  PHE*     1.3    65.4    +      -       -      +
     94D  TRP      3.4     0.2    -      -       -      -
     95D  PRO*     3.4     6.6    -      -       -      +
     96D  ASN*     3.1    45.2    +      -       -      +
    171D  VAL*     3.9    36.6    -      -       +      +
    172D  LEU      4.6     0.7    -      -       -      +
    174D  ALA*     4.5     2.7    -      -       +      -
    209D  ARG*     4.0    21.5    -      -       -      +
    220D  LEU*     4.2     5.8    -      -       +      -
    304D  ACT      4.1    14.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 93 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34D  ILE*     5.0     3.1    -      -       +      -
     39D  MSE      5.8     0.9    -      -       -      -
     42D  HIS*     4.0    15.5    -      +       -      -
     89D  LEU      2.8    19.0    +      -       -      +
     90D  HIS*     3.4    14.8    -      +       -      +
     92D  ILE*     1.3    74.8    -      -       -      +
     94D  TRP*     1.3   107.3    +      +       -      +
     96D  ASN*     3.2    19.9    +      -       -      +
     97D  MSE      3.5    28.6    +      -       +      +
    141D  TRP*     3.7    13.7    -      +       +      -
    174D  ALA*     3.2    22.2    -      -       -      -
    175D  LEU*     4.1     2.7    -      -       -      -
    176D  ASP*     3.4    23.3    -      -       +      -
    193D  TYR*     3.8    20.2    -      -       -      -
    197D  TRP*     4.1    12.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 94 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21D  PRO*     4.5     7.9    -      -       +      -
     22D  PRO      5.7     0.9    -      -       -      -
     23D  LEU*     3.4    21.8    -      -       +      -
     24D  PRO*     4.0    11.4    -      -       +      -
     25D  TYR*     2.9    20.1    +      -       -      -
     39D  MSE      3.4    33.2    -      -       +      -
     42D  HIS*     3.6    33.0    -      +       +      -
     43D  HIS*     3.5    32.9    -      +       +      -
     47D  HIS*     3.0    27.1    +      +       -      -
     90D  HIS*     2.9    36.3    +      +       -      -
     91D  SER*     4.2     4.9    -      -       -      -
     93D  PHE*     1.3   102.0    -      +       -      +
     95D  PRO*     1.3    65.8    -      -       +      +
     97D  MSE      2.9    23.3    +      -       +      +
----------------------------------------------------------
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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