Contacts of the helix formed by residues 2 - 33 (chain A) in PDB entry 1W5J


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 ARG 2 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1A  TYZ      1.3    71.2    -      -       -      +
      3A  MET*     1.3    65.2    +      -       -      +
      4A  ARG*     3.1    16.0    -      -       +      +
      5A  GLN*     3.1    60.3    +      -       +      +
      6A  ILE*     3.2    13.3    +      -       -      +
     33B  ARG*     3.8     0.4    -      -       -      -
     32C  GLU*     3.8    23.3    -      -       -      +
     33C  ARG*     3.6    14.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET 3 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      2A  ARG*     1.3    72.6    -      -       -      +
      4A  ARG*     1.3    62.3    +      -       -      +
      6A  ILE*     3.2    15.0    +      -       +      +
      7A  GLU*     3.0    43.2    +      -       -      +
     30B  LEU*     3.9    21.3    -      -       +      -
     33B  ARG*     3.3    35.7    -      -       -      +
     33C  ARG*     3.0    21.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 4 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      2A  ARG*     3.1    14.7    -      -       +      +
      3A  MET*     1.3    77.2    -      -       -      +
      5A  GLN*     1.3    56.7    +      -       +      +
      7A  GLU*     3.3    24.4    +      -       -      +
      8A  ASP*     3.0    49.1    +      -       -      +
     11A  GLU*     5.2     6.3    +      -       -      -
     33C  ARG      5.1     0.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 5 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1A  TYZ      3.0    31.7    -      -       +      +
      2A  ARG*     3.1    54.7    +      -       -      +
      4A  ARG*     1.3    74.5    -      -       +      +
      6A  ILE*     1.4    61.2    +      -       +      +
      8A  ASP*     3.6     7.7    +      -       -      +
      9A  ARG*     3.0    28.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 6 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1A  TYZ      5.0     4.9    -      -       +      +
      2A  ARG      3.2    13.2    +      -       -      +
      3A  MET*     3.2    19.9    +      -       -      +
      5A  GLN*     1.4    74.2    -      -       +      +
      7A  GLU*     1.3    67.5    +      -       +      +
      9A  ARG*     3.2     6.5    +      -       -      +
     10A  LEU*     3.0    33.0    +      -       +      +
     26B  ILE*     3.8    30.2    -      -       +      +
     29B  LEU*     4.1    34.8    -      -       +      -
     30B  LEU*     3.7    31.2    -      -       +      +
     33B  ARG*     4.8     8.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 7 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3A  MET*     3.0    43.0    +      -       +      +
      4A  ARG*     3.3    34.1    +      -       -      +
      6A  ILE*     1.3    78.1    -      -       +      +
      8A  ASP*     1.3    66.0    +      -       -      +
     10A  LEU*     3.4    11.8    +      -       +      +
     11A  GLU*     3.0    33.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 8 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      4A  ARG*     3.0    40.6    +      -       -      +
      5A  GLN*     3.8     6.4    -      -       -      +
      7A  GLU*     1.3    76.1    -      -       -      +
      9A  ARG*     1.3    52.1    +      -       -      +
     11A  GLU*     3.1    17.0    +      -       -      +
     12A  GLU*     2.8    51.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 9 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      5A  GLN      3.0    18.1    +      -       -      +
      6A  ILE*     3.2     6.5    +      -       -      +
      8A  ASP*     1.3    72.7    -      -       -      +
     10A  LEU*     1.3    59.6    +      -       -      +
     12A  GLU*     3.1    27.1    +      -       -      +
     13A  ILE*     2.7    44.2    +      -       +      +
     22B  GLU*     3.9    26.6    -      -       +      +
     25B  ARG*     5.6     7.5    -      -       -      +
     26B  ILE*     3.8    21.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 10 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6A  ILE*     3.0    28.3    +      -       +      +
      7A  GLU*     3.6    13.9    -      -       +      +
      9A  ARG*     1.3    79.3    -      -       -      +
     11A  GLU*     1.3    61.3    +      -       +      +
     13A  ILE*     3.2     9.2    +      -       +      +
     14A  LEU*     3.0    33.1    +      -       +      +
     23B  LEU*     4.2    19.1    -      -       +      -
     26B  ILE*     4.1    23.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 11 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      4A  ARG*     5.2     5.9    +      -       -      -
      7A  GLU*     3.0    27.2    +      -       +      +
      8A  ASP*     3.1    18.2    +      -       -      +
     10A  LEU*     1.3    79.4    -      -       +      +
     12A  GLU*     1.3    58.4    +      -       +      +
     14A  LEU*     3.3    13.3    +      -       +      +
     15A  SER*     2.9    32.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 12 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8A  ASP*     2.8    36.3    +      -       +      +
      9A  ARG*     3.1    29.5    +      -       -      +
     11A  GLU*     1.3    73.7    -      -       +      +
     13A  ILE*     1.4    62.3    +      -       -      +
     15A  SER*     3.3     9.1    +      -       -      -
     16A  LYS*     3.2    22.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 13 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  ARG*     2.7    43.7    +      -       +      +
     10A  LEU*     3.6     9.6    -      -       +      +
     12A  GLU*     1.4    69.9    -      -       -      +
     14A  LEU*     1.3    62.3    +      -       +      +
     16A  LYS*     3.1     7.6    +      -       -      +
     17A  LEU*     2.8    47.5    +      -       +      +
     19B  ILE*     4.0    25.5    -      -       +      +
     22B  GLU*     4.0    17.5    -      -       +      -
     23B  LEU*     4.0    31.2    -      -       +      -
     26B  ILE*     4.0    10.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 14 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  LEU*     3.0    21.7    +      -       +      +
     11A  GLU*     3.4    16.8    -      -       +      +
     13A  ILE*     1.3    79.2    -      -       +      +
     15A  SER*     1.3    65.9    +      -       -      +
     17A  LEU*     3.8    15.8    -      -       +      +
     18A  TYR*     2.9    56.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 15 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11A  GLU      2.9    18.7    +      -       -      -
     12A  GLU*     3.6    11.0    -      -       -      -
     13A  ILE      3.3     0.4    -      -       -      -
     14A  LEU*     1.3    75.6    -      -       -      +
     16A  LYS*     1.4    58.9    +      -       -      +
     18A  TYR*     3.3     8.8    +      -       -      +
     19A  HIS*     3.0    27.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 16 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  GLU      3.2     9.1    +      -       -      +
     13A  ILE*     3.1     9.5    +      -       -      +
     15A  SER*     1.4    80.1    -      -       -      +
     17A  LEU*     1.3    50.8    +      -       -      +
     19A  HIS*     3.2    31.7    +      -       -      +
     20A  ILE*     2.7    41.5    +      -       +      +
     15B  LYS*     3.7    50.2    -      -       +      +
     19B  ILE*     4.0    11.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 17 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13A  ILE*     2.8    36.3    +      -       +      +
     14A  LEU*     3.2    15.2    +      -       +      +
     16A  LYS*     1.3    76.2    -      -       -      +
     18A  TYR*     1.3    62.4    +      -       +      +
     20A  ILE*     3.7     6.9    -      -       +      +
     21A  CYS*     2.8    41.4    +      -       -      -
     16B  LEU*     3.7    30.3    -      -       +      -
     19B  ILE*     3.8    17.0    -      -       +      -
     23B  LEU*     5.8     2.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 18 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14A  LEU*     2.9    52.4    +      -       +      +
     15A  SER*     3.7     7.6    -      -       -      +
     17A  LEU*     1.3    77.2    -      -       +      +
     19A  HIS*     1.3    58.8    +      -       -      +
     21A  CYS*     3.3    11.4    +      -       +      +
     22A  ASN*     3.0    36.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 19 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15A  SER      3.0    12.7    +      -       -      +
     16A  LYS*     3.3    33.2    +      -       +      +
     18A  TYR*     1.3    74.3    -      -       -      +
     20A  ILE*     1.3    67.5    +      -       -      +
     22A  ASN*     3.4    12.7    +      -       +      +
     23A  GLU*     3.0    35.0    +      -       +      +
      8B  ARG*     3.8    24.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 20 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  LYS*     2.7    32.8    +      -       +      +
     17A  LEU*     3.7     8.5    -      -       +      +
     19A  HIS*     1.3    75.7    -      -       -      +
     21A  CYS*     1.3    60.1    +      -       -      +
     23A  GLU*     3.2     8.4    +      -       -      +
     24A  LEU*     2.8    39.9    +      -       +      +
     12B  ILE*     3.8    28.5    -      -       +      +
     15B  LYS*     3.8    27.1    -      -       +      -
     16B  LEU*     3.6    38.4    -      -       +      +
     19B  ILE*     4.3     7.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 21 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  LEU*     2.8    31.3    +      -       -      +
     18A  TYR*     3.6    12.6    -      -       +      +
     20A  ILE*     1.3    80.0    -      -       -      +
     22A  ASN*     1.3    58.2    +      -       -      +
     24A  LEU*     3.1    12.2    +      -       -      +
     25A  ALA*     2.8    30.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 22 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  TYR*     3.0    23.3    +      -       -      +
     19A  HIS*     3.5    16.4    -      -       +      +
     21A  CYS*     1.3    77.8    -      -       -      +
     23A  GLU*     1.3    60.5    +      -       -      +
     25A  ALA*     3.3     8.4    +      -       -      +
     26A  ARG*     3.0    28.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 23 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  HIS*     3.0    28.3    +      -       +      +
     20A  ILE*     3.4    10.5    -      -       -      +
     22A  ASN*     1.3    78.5    -      -       -      +
     24A  LEU*     1.3    66.8    +      -       -      +
     26A  ARG*     3.0    39.2    +      -       -      +
     27A  ILE*     3.1    28.2    +      -       +      +
      8B  ARG*     2.9    42.6    +      -       -      +
     12B  ILE*     4.2    16.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 24 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  ILE*     2.8    38.4    +      -       +      +
     21A  CYS*     3.1    10.3    +      -       -      +
     23A  GLU*     1.3    74.2    -      -       -      +
     25A  ALA*     1.3    62.2    +      -       -      +
     27A  ILE*     3.2     7.2    +      -       +      +
     28A  ARG*     3.0    23.4    +      -       -      +
      9B  LEU*     3.8    20.2    -      -       +      -
     12B  ILE*     3.7    29.8    -      -       +      -
     16B  LEU*     5.5     3.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 25 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  CYS      2.8    19.4    +      -       -      +
     22A  ASN*     3.7     8.1    -      -       -      +
     24A  LEU*     1.3    72.9    -      -       -      +
     26A  ARG*     1.3    63.0    +      -       -      +
     28A  ARG*     3.4    10.2    +      -       -      +
     29A  ARG*     3.1    22.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 26 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  ASN      3.0    16.6    +      -       -      +
     23A  GLU*     3.0    39.9    +      -       -      +
     24A  LEU      3.2     0.2    -      -       -      -
     25A  ALA*     1.3    76.4    -      -       -      +
     27A  ILE*     1.3    58.2    +      -       -      +
     29A  ARG*     3.2     9.2    +      -       +      +
     30A  LEU*     2.8    69.7    +      -       +      +
      8B  ARG*     4.8     9.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 27 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23A  GLU      3.1    19.0    +      -       -      +
     24A  LEU*     3.2     9.6    +      -       +      +
     26A  ARG*     1.3    74.6    -      -       -      +
     28A  ARG*     1.3    68.7    +      -       -      +
     30A  LEU*     3.0    15.9    +      -       +      +
     31A  LEU*     2.8    36.2    +      -       +      +
      5B  ILE*     3.8    29.6    -      -       +      +
      8B  ARG*     4.0    22.4    -      -       +      -
      9B  LEU*     4.0    22.4    -      -       +      -
     12B  ILE*     3.7    27.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 28 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  LEU      3.0    11.8    +      -       -      +
     25A  ALA*     3.5    13.2    +      -       -      +
     27A  ILE*     1.3    78.9    -      -       -      +
     29A  ARG*     1.3    57.8    -      -       -      +
     31A  LEU*     3.2    11.5    +      -       -      +
     32A  GLY*     3.0    22.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 29 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  ALA      3.1    13.8    +      -       -      +
     26A  ARG*     3.5     9.6    -      -       +      +
     27A  ILE      3.1     0.2    -      -       -      -
     28A  ARG*     1.3    79.0    -      -       -      +
     30A  LEU*     1.4    64.4    +      -       +      +
     32A  GLY*     3.2     4.4    +      -       -      +
     33A  GLU*     3.2    36.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 30 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26A  ARG*     2.8    55.0    +      -       +      +
     27A  ILE*     3.7    12.3    -      -       +      +
     29A  ARG*     1.4    74.7    -      -       +      +
     31A  LEU*     1.3    63.6    +      -       -      +
     33A  GLU*     3.0    37.7    +      -       +      +
     34A  ARG*     3.5    13.5    +      -       -      +
      1B  ARG*     5.2    17.7    -      -       -      -
      5B  ILE*     4.3    28.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 31 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  ILE*     2.8    32.3    +      -       +      +
     28A  ARG*     3.5    11.7    -      -       -      +
     30A  LEU*     1.3    73.4    -      -       -      +
     32A  GLY*     1.3    62.2    +      -       -      +
     33A  GLU      3.2     1.0    +      -       -      -
     34A  ARG*     3.4    23.0    +      -       -      +
      2B  MET*     3.8    25.1    -      -       +      -
      5B  ILE*     3.8    27.8    -      -       +      -
      9B  LEU*     6.2     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 32 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28A  ARG      3.0    12.9    +      -       -      -
     29A  ARG*     3.2     6.2    +      -       -      -
     30A  LEU      3.2     0.4    -      -       -      -
     31A  LEU*     1.3    80.1    -      -       -      +
     33A  GLU*     1.3    55.8    +      -       -      +
     34A  ARG      3.4     3.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 33 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  ARG*     3.2    24.6    +      -       -      +
     30A  LEU*     3.0    41.1    +      -       +      +
     32A  GLY*     1.3    76.9    -      -       -      +
     34A  ARG*     1.3    65.1    +      -       -      +
----------------------------------------------------------
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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