Contacts of the helix formed by residues 15 - 39 (chain P) in PDB entry 1TQE


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 15 (chain P).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1D    T      3.4    44.5    +      -       +      +
     13P  ASP*     2.9    21.8    +      -       -      +
     14P  GLN*     1.3    85.0    +      -       +      +
     16P  ASN*     1.3    59.4    +      -       -      +
     18P  GLN*     3.1    19.3    +      -       -      +
     19P  VAL*     3.1    19.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 16 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13C    A      5.2    14.3    -      -       -      +
     14C    A      5.5     8.1    +      -       -      -
     11P  ILE*     2.9    33.4    -      -       +      +
     13P  ASP*     2.7    28.5    +      -       +      +
     15P  ARG*     1.3    68.3    -      -       -      +
     17P  ARG*     1.3    57.3    +      -       -      +
     18P  GLN      3.0     5.2    -      -       -      -
     19P  VAL*     3.9    10.0    -      -       -      +
     20P  THR*     3.0    40.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 17 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10P  ARG*     2.8    45.9    -      -       -      +
     11P  ILE*     2.9    44.8    +      -       +      +
     12P  LEU      3.3    20.8    +      -       -      -
     13P  ASP      2.8    15.4    +      -       -      +
     14P  GLN*     3.6    33.1    -      -       -      +
     16P  ASN*     1.3    72.3    -      -       -      +
     18P  GLN*     1.3    57.8    +      -       -      +
     21P  PHE*     3.6    20.9    +      -       -      +
     50P  SER*     5.1     8.7    +      -       -      -
     38Q  LEU      4.1     7.9    -      -       -      -
     39Q  CYS*     4.0    27.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 18 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1D    T      5.8     8.5    -      -       +      +
     14P  GLN*     3.4    18.0    +      -       +      +
     15P  ARG*     3.1     6.4    +      -       -      +
     16P  ASN      3.0     0.4    -      -       -      -
     17P  ARG*     1.3    80.6    -      -       -      +
     19P  VAL*     1.3    64.5    +      -       +      +
     20P  THR      3.3     1.6    -      -       -      -
     21P  PHE*     3.9    14.2    -      -       -      +
     22P  THR*     3.4    30.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 19 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14C    A      6.3     0.9    -      -       -      +
      1D    T      5.2    12.6    -      -       +      +
      2D    T      6.1     4.9    -      -       +      -
      3D    G      6.3     0.9    -      -       -      +
      4D    C      6.3     0.2    -      -       -      +
     15P  ARG      3.1    19.3    +      -       -      +
     16P  ASN*     3.9    11.0    -      -       -      +
     18P  GLN*     1.3    78.2    -      -       +      +
     20P  THR*     1.3    60.8    +      -       -      +
     22P  THR*     3.5     4.6    +      -       -      +
     23P  LYS*     3.1    50.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 20 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13C    A      3.7    25.2    +      -       -      +
      6P  ILE*     6.0     0.2    -      -       +      -
     11P  ILE*     3.6    26.4    -      -       +      +
     16P  ASN*     3.0    25.6    +      -       -      -
     17P  ARG      4.7     0.2    -      -       -      -
     19P  VAL*     1.3    78.8    -      -       -      +
     21P  PHE*     1.3    66.2    +      -       -      +
     23P  LYS*     4.4     7.0    -      -       +      -
     24P  ARG*     2.8    45.5    +      -       +      +
     38Q  LEU*     4.6     3.8    -      -       +      -
     39Q  CYS*     4.2     7.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 21 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17P  ARG      3.6    13.0    +      -       -      +
     18P  GLN*     3.7    16.0    +      -       -      +
     19P  VAL      3.4     0.6    -      -       -      -
     20P  THR*     1.3    76.2    -      -       -      +
     22P  THR*     1.3    67.2    +      -       -      +
     25P  LYS*     2.9    65.0    +      -       +      +
     47P  ILE*     4.1    15.7    -      -       +      -
     49P  ASN*     4.4    18.2    -      -       +      -
     55P  PHE*     3.9    28.7    -      +       -      -
     35Q  LEU*     3.9    11.3    -      -       +      +
     39Q  CYS*     3.4    37.3    -      -       +      -
     41Q  CYS*     3.8    21.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 22 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18P  GLN*     3.4    25.5    +      -       -      -
     19P  VAL*     3.8     8.3    -      -       -      +
     20P  THR      3.2     0.6    -      -       -      -
     21P  PHE*     1.3    85.8    -      -       -      +
     23P  LYS*     1.3    69.2    +      -       +      +
     25P  LYS*     4.0    14.9    +      -       -      +
     26P  PHE*     3.3    19.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 23 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12C    T      4.4    22.7    +      -       +      +
     13C    A      2.9    40.4    +      -       +      +
     14C    A      3.1    24.9    +      -       -      +
     15C    G      5.0     0.2    +      -       -      -
      4D    C      4.8     8.5    -      -       -      +
      5D    T      4.5     1.8    +      -       -      -
     19P  VAL*     3.1    38.4    +      -       +      +
     20P  THR*     3.7     6.5    -      -       +      +
     22P  THR*     1.3    82.4    -      -       +      +
     24P  ARG*     1.3    67.6    +      -       +      +
     26P  PHE*     3.2    11.5    +      -       -      +
     27P  GLY*     3.2     8.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 24 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12C    T      3.6    34.0    +      -       -      +
     13C    A      3.0    32.6    +      -       -      +
      6P  ILE*     4.6     6.9    -      -       -      +
      8P  ILE*     6.0     1.0    -      -       -      +
     20P  THR*     2.8    29.7    +      -       +      +
     23P  LYS*     1.3    71.9    -      -       +      +
     25P  LYS*     1.3    69.1    +      -       -      +
     26P  PHE      2.9     1.8    -      -       -      -
     27P  GLY*     2.6    15.5    +      -       -      +
     28P  LEU*     2.8    13.2    +      -       -      -
     31Q  LYS*     4.3    11.3    +      -       -      +
     34Q  GLU*     2.8    41.0    +      -       -      +
     35Q  LEU*     4.2    20.2    -      -       +      +
     38Q  LEU*     3.3    27.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 25 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21P  PHE*     2.9    44.6    +      -       +      +
     22P  THR*     4.0    17.0    +      -       -      +
     24P  ARG*     1.3    71.9    -      -       -      +
     26P  PHE*     1.3    75.3    +      -       -      +
     28P  LEU*     3.4     2.8    +      -       -      +
     29P  MET*     3.0    36.0    +      -       -      +
     47P  ILE*     3.6    16.8    -      -       +      -
     55P  PHE*     3.6    34.1    -      -       +      -
     35Q  LEU*     3.6    19.3    -      -       +      +
     77Q  GLU*     3.5    30.4    +      -       -      +
     79Q  ARG*     5.1     2.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 26 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22P  THR      3.3     9.0    +      -       -      +
     23P  LYS*     3.2    11.8    +      -       -      +
     24P  ARG      2.6     4.6    +      -       -      -
     25P  LYS*     1.3    80.5    -      -       -      +
     27P  GLY*     1.3    57.5    +      -       -      +
     29P  MET*     3.1     7.9    +      -       +      +
     30P  LYS*     2.7    43.1    +      -       +      +
     79Q  ARG*     3.4    31.0    -      -       -      -
     84Q  ILE*     3.6    23.8    -      -       +      -
     87Q  THR*     3.9    20.9    -      -       +      -
     88Q  LEU*     3.5    35.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 27 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11C    A      5.3     5.6    +      -       -      -
     12C    T      4.1    19.3    -      -       -      -
     23P  LYS      3.2     4.6    +      -       -      -
     24P  ARG      2.6    11.4    +      -       -      -
     26P  PHE*     1.3    79.2    -      -       -      +
     28P  LEU*     1.3    60.7    +      -       -      -
     30P  LYS*     3.0    14.0    +      -       -      +
     31P  LYS*     2.9    28.4    +      -       -      +
     31Q  LYS*     5.3     2.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 28 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12C    T      5.2     0.4    +      -       -      -
     24P  ARG      2.8    14.1    +      -       -      +
     25P  LYS*     3.5     9.6    -      -       -      +
     27P  GLY*     1.3    73.1    -      -       -      +
     29P  MET*     1.3    63.9    +      -       -      +
     31P  LYS*     3.0     5.5    +      -       -      +
     32P  ALA*     2.9    19.6    +      -       -      +
     45P  LEU*     3.8    30.3    -      -       +      -
     47P  ILE*     4.4     6.1    -      -       +      -
     28Q  LEU*     3.6    20.8    -      -       +      +
     31Q  LYS*     3.4    22.7    -      -       +      +
     32Q  ALA*     3.2    40.4    -      -       +      +
     35Q  LEU*     3.7    24.7    -      -       +      -
     43Q  ILE*     4.6     2.7    -      -       +      -
     45Q  LEU*     6.1     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 29 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25P  LYS*     3.0    25.8    -      -       +      +
     26P  PHE*     3.1     8.2    +      -       -      +
     28P  LEU*     1.3    76.2    -      -       -      +
     30P  LYS*     1.3    63.6    +      -       -      +
     32P  ALA*     3.4     9.2    -      -       -      +
     33P  TYR*     2.8    25.3    +      -       -      +
     45P  LEU*     4.0    16.4    -      -       +      +
     47P  ILE*     4.8     8.5    -      -       +      -
     55P  PHE      4.7     1.6    -      -       -      -
     56P  GLN*     2.9    45.5    -      -       -      +
     57P  TYR*     3.2    20.3    -      -       +      -
     77Q  GLU*     4.2    10.5    -      -       -      +
     79Q  ARG*     3.8    26.2    -      -       +      -
     84Q  ILE*     4.1    14.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 30 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10C    T      4.2     1.8    +      -       -      -
     11C    A      2.5    43.8    +      -       -      +
     26P  PHE*     2.7    29.2    +      -       +      +
     27P  GLY*     3.2    14.4    -      -       -      +
     29P  MET*     1.3    75.4    -      -       -      +
     31P  LYS*     1.3    58.0    +      -       -      +
     33P  TYR*     3.2    13.6    -      -       +      -
     34P  GLU*     2.8    43.9    +      -       +      +
     84Q  ILE*     4.5     7.1    -      -       -      +
     88Q  LEU*     4.3    38.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 31 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10C    T      4.6     3.0    +      -       -      -
     11C    A      4.0    36.3    +      -       -      +
     11D    A      3.5    19.5    +      -       -      -
     12D    T      3.1    31.9    +      -       -      +
     27P  GLY      2.9    15.1    +      -       -      +
     28P  LEU*     3.5     7.9    -      -       -      +
     30P  LYS*     1.3    73.6    -      -       -      +
     32P  ALA*     1.3    70.5    +      -       -      +
     34P  GLU*     2.9    21.5    +      -       -      +
     35P  LEU*     2.7    22.2    +      -       -      +
     24Q  ARG*     4.4     6.6    +      -       -      +
     27Q  GLY      5.3     0.9    -      -       -      -
     28Q  LEU*     3.5    21.8    -      -       +      +
     31Q  LYS*     4.2    21.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 32 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28P  LEU      2.9    12.8    +      -       -      +
     29P  MET*     3.4    12.1    -      -       -      +
     31P  LYS*     1.3    79.6    -      -       -      +
     33P  TYR*     1.3    64.4    +      -       -      +
     35P  LEU*     2.9     2.6    +      -       -      +
     36P  SER*     2.7    21.0    +      -       -      -
     43P  ILE*     3.6     8.8    -      -       +      +
     45P  LEU*     4.6     7.0    -      -       +      -
     57P  TYR*     3.5    28.0    -      -       +      -
     28Q  LEU*     3.1    24.7    -      -       +      +
     45Q  LEU*     5.6     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 33 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29P  MET      2.8    16.1    +      -       -      +
     30P  LYS*     3.2    15.0    -      -       +      +
     32P  ALA*     1.3    72.6    -      -       -      +
     34P  GLU*     1.3    88.4    +      -       +      +
     36P  SER*     3.0     3.5    -      -       -      -
     37P  VAL*     3.0    37.0    +      -       +      +
     57P  TYR*     3.0     7.2    +      -       +      +
      8Q  ILE*     3.9    25.4    +      -       +      +
     81Q  ASN*     2.8    56.5    -      -       +      +
     84Q  ILE*     4.1    19.7    -      -       +      -
     85Q  LEU*     3.9    28.5    -      -       +      +
     88Q  LEU*     4.3    15.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 34 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10C    T      5.1     1.8    -      -       -      +
     11C    A      4.3     5.2    +      -       -      -
     30P  LYS*     2.8    45.9    +      -       +      +
     31P  LYS*     2.9    19.1    +      -       -      +
     33P  TYR*     1.3    88.3    -      -       +      +
     35P  LEU*     1.3    68.0    +      -       -      +
     37P  VAL*     2.9     3.6    +      -       -      +
     38P  LEU*     2.8    33.1    +      -       +      +
      8Q  ILE*     4.3    23.4    -      -       +      +
     24Q  ARG*     2.8    34.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 35 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31P  LYS      2.7    15.7    +      -       -      +
     32P  ALA*     3.4     7.4    -      -       -      +
     34P  GLU*     1.3    71.8    -      -       -      +
     36P  SER*     1.3    62.6    +      -       -      +
     38P  LEU*     4.5     6.7    -      -       -      -
     39P  CYS*     3.1    43.7    +      -       -      +
     41P  CYS*     3.7     5.9    -      -       -      -
     43P  ILE*     4.0     8.1    -      -       +      -
     21Q  PHE*     3.9    19.1    -      -       +      +
     24Q  ARG*     4.0    25.1    -      -       +      +
     25Q  LYS*     3.5    31.2    -      -       +      +
     28Q  LEU*     3.8    21.3    -      -       +      -
     47Q  ILE*     4.1    11.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 36 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32P  ALA      2.7    11.9    +      -       -      -
     33P  TYR      3.0    10.1    -      -       -      -
     34P  GLU      2.9     0.6    +      -       -      -
     35P  LEU*     1.3    76.7    -      -       -      +
     37P  VAL*     1.3    58.0    -      -       -      +
     40P  ASP*     3.1     9.0    +      -       -      -
     41P  CYS*     3.0    39.7    +      -       -      +
     43P  ILE*     3.8     8.7    -      -       -      +
     57P  TYR*     3.7     7.9    -      -       -      -
     59P  SER*     3.0    25.7    -      -       -      -
     81Q  ASN*     3.0    14.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 37 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33P  TYR*     3.0    34.6    +      -       +      +
     34P  GLU      2.9     6.7    +      -       -      -
     36P  SER*     1.3    71.1    -      -       -      +
     38P  LEU*     1.3    67.2    +      -       -      +
     40P  ASP*     3.2    10.1    +      -       -      +
      8Q  ILE*     3.5    37.0    -      -       +      +
      9Q  SER*     3.6    10.3    -      -       -      -
     10Q  ARG*     3.3    13.5    +      -       -      +
     81Q  ASN*     4.3     9.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 38 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34P  GLU*     2.8    24.0    +      -       +      +
     35P  LEU      4.2     0.7    -      -       -      +
     37P  VAL*     1.3    74.5    -      -       -      +
     39P  CYS*     1.3    66.9    +      -       -      +
     40P  ASP      3.5     0.5    +      -       -      -
      6Q  ILE*     4.1    15.7    -      -       +      -
      7Q  GLN      4.0    20.4    -      -       -      +
      8Q  ILE*     4.2    15.5    -      -       +      -
      9Q  SER      4.2     8.3    -      -       -      +
     10Q  ARG*     3.3     1.9    -      -       -      -
     11Q  ILE*     2.8    50.4    +      -       +      +
     17Q  ARG*     3.9     1.0    -      -       -      +
     20Q  THR*     4.6     3.6    -      -       +      -
     24Q  ARG*     3.2    51.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 39 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35P  LEU*     3.1    23.3    +      -       -      +
     36P  SER      4.0     0.4    -      -       -      -
     38P  LEU*     1.3    80.6    -      -       -      +
     40P  ASP*     1.3    71.7    +      -       -      +
     41P  CYS*     3.3     5.2    +      -       -      +
     11Q  ILE*     4.8     0.2    -      -       -      -
     17Q  ARG*     3.9    26.0    +      -       +      +
     20Q  THR*     4.0    14.1    -      -       -      -
     21Q  PHE*     3.3    57.7    -      -       +      -
     49Q  ASN*     5.7     0.9    -      -       -      +
     50Q  SER*     4.8     2.8    +      -       -      -
----------------------------------------------------------
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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