Contacts of the helix formed by residues 65 - 89 (chain D) in PDB entry 2IT0


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 THR 65 (chain D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52D  GLY*     2.9    31.8    +      -       -      +
     53D  LEU      2.9    21.8    +      -       -      -
     54D  LEU*     3.8     8.7    -      -       -      +
     55D  ARG*     4.2    21.5    -      -       -      +
     64D  LEU*     1.3    75.5    -      -       -      +
     66D  GLU*     1.3    60.4    +      -       -      +
     67D  LYS*     3.6     2.8    +      -       -      -
     68D  GLY      2.9    11.6    +      -       -      -
     69D  ARG*     2.9    26.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 66 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65D  THR*     1.3    75.8    -      -       -      +
     67D  LYS*     1.3    66.3    +      -       -      +
     69D  ARG*     3.3     8.5    +      -       -      +
     70D  ALA*     3.1    22.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 67 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51D  ASP*     3.3    22.4    +      -       -      +
     52D  GLY      4.1     8.3    -      -       -      +
     53D  LEU*     4.0    20.0    -      -       +      +
     65D  THR*     3.9     6.7    -      -       -      +
     66D  GLU*     1.3    81.9    -      -       -      +
     68D  GLY*     1.3    61.9    +      -       -      +
     70D  ALA*     3.2     8.9    +      -       -      +
     71D  LEU*     3.1    37.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 68 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12D  LEU*     3.6    15.2    -      -       -      +
     53D  LEU*     3.4    34.0    -      -       -      +
     64D  LEU*     4.0     6.8    -      -       -      +
     65D  THR*     2.9    10.7    +      -       -      -
     67D  LYS*     1.3    74.3    -      -       -      +
     69D  ARG*     1.3    64.1    +      -       -      +
     71D  LEU*     3.7     1.7    +      -       -      +
     72D  ALA*     3.2    22.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 69 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16D  TYR*     3.5    23.2    +      -       +      -
     19D  GLU*     2.8    42.1    +      -       -      -
     64D  LEU*     3.9    28.0    +      -       +      +
     65D  THR      2.9    19.9    +      -       -      +
     66D  GLU*     3.6     9.6    -      -       -      +
     68D  GLY*     1.3    72.7    -      -       -      +
     70D  ALA*     1.3    72.0    +      -       -      +
     72D  ALA*     3.1     3.1    +      -       -      +
     73D  ILE*     3.0    40.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 70 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66D  GLU*     3.1    10.9    +      -       +      +
     67D  LYS*     3.5    10.8    -      -       -      +
     69D  ARG*     1.3    81.6    -      -       -      +
     71D  LEU*     1.3    69.6    +      -       +      +
     73D  ILE*     2.9    19.9    +      -       -      +
     74D  ALA*     3.1    12.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 71 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8D  THR*     6.3     0.2    -      -       +      -
      9D  GLU*     6.3     0.7    -      -       +      -
     12D  LEU*     4.2    17.5    -      -       +      -
     53D  LEU*     4.0    26.9    -      -       +      -
     67D  LYS*     3.1    24.5    +      -       +      +
     68D  GLY      4.0     5.2    -      -       -      +
     69D  ARG      3.3     0.2    -      -       -      -
     70D  ALA*     1.3    82.4    -      -       +      +
     72D  ALA*     1.3    62.9    +      -       -      +
     74D  ALA*     3.2    10.9    +      -       +      +
     75D  VAL*     3.1    27.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 72 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12D  LEU*     3.9    36.5    -      -       +      +
     13D  ARG*     5.1     1.9    -      -       -      +
     16D  TYR*     4.1    20.4    -      -       +      -
     64D  LEU*     4.2     5.2    -      -       +      -
     68D  GLY      3.2    15.2    +      -       -      +
     69D  ARG      3.1     5.4    +      -       -      +
     71D  LEU*     1.3    75.3    -      -       -      +
     73D  ILE*     1.3    68.0    +      -       -      +
     75D  VAL*     2.9    16.5    +      -       -      +
     76D  MET*     2.9    14.9    +      -       -      +
----------------------------------------------------------
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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
----------------------------------------------------------
     16D  TYR*     3.9    26.5    -      -       +      +
     69D  ARG*     3.0    35.3    +      -       +      +
     70D  ALA*     2.9    12.4    +      -       -      +
     72D  ALA*     1.3    76.3    -      -       -      +
     74D  ALA*     1.3    53.3    +      -       -      +
     76D  MET*     3.1     7.8    +      -       -      +
     77D  ARG*     2.8    35.3    +      -       -      +
    133D  PRO*     3.9     6.5    -      -       +      +
    134D  GLY*     3.3    39.0    -      -       -      +
    137D  GLU*     4.0    16.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 74 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70D  ALA      3.1     8.7    +      -       -      +
     71D  LEU*     3.5    14.4    -      -       +      +
     73D  ILE*     1.3    80.9    -      -       -      +
     75D  VAL*     1.3    59.9    +      -       +      +
     77D  ARG*     3.5    30.4    +      -       -      +
     78D  LYS*     3.1    42.0    +      -       -      +
    110D  GLU*     5.6     2.7    -      -       -      +
    113D  GLU*     4.0     0.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 75 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9D  GLU*     3.6    52.0    -      -       +      +
     12D  LEU*     5.6     0.4    -      -       +      -
     13D  ARG*     4.4     7.9    -      -       +      -
     71D  LEU*     3.1    17.7    +      -       +      +
     72D  ALA*     2.9    12.7    +      -       -      +
     74D  ALA*     1.3    71.2    -      -       +      +
     76D  MET*     1.3    59.3    +      -       -      +
     78D  LYS*     3.8     9.8    -      -       -      +
     79D  HIS*     3.0    27.0    +      -       -      +
    105D  GLU*     3.7    34.5    -      -       +      +
    106D  HIS*     4.1     6.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 76 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13D  ARG*     4.4    15.2    -      -       +      +
     16D  TYR*     3.0    39.9    -      -       +      -
     17D  ASP*     3.7    20.2    -      -       -      +
     20D  GLU*     3.7     9.4    -      -       -      +
     72D  ALA      2.9    10.7    +      -       -      +
     73D  ILE*     3.4     9.4    -      -       -      +
     75D  VAL*     1.3    77.0    -      -       -      +
     77D  ARG*     1.3    65.5    +      -       -      +
     79D  HIS*     3.3     8.8    +      -       -      +
     80D  ARG*     3.1    67.9    +      -       -      +
    133D  PRO*     3.4    23.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 77 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73D  ILE*     2.8    17.0    +      -       -      +
     74D  ALA*     3.6    30.5    -      -       -      +
     76D  MET*     1.3    78.2    -      -       -      +
     78D  LYS*     1.3    56.1    +      -       -      +
     80D  ARG*     4.1     0.2    -      -       -      -
     81D  LEU*     3.0    39.9    +      -       +      +
    110D  GLU*     4.1    20.4    +      -       -      +
    113D  GLU*     2.8    29.2    +      -       -      +
    132D  ILE*     4.1    15.3    -      -       +      +
    133D  PRO*     3.2    21.7    -      -       -      +
    134D  GLY*     2.9    41.4    +      -       -      -
    135D  LEU*     4.0     4.0    -      -       +      +
    137D  GLU*     4.4     9.3    -      -       -      +
    138D  LEU*     3.4    28.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 78 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9D  GLU*     6.0     2.0    -      -       -      -
     74D  ALA*     3.1    31.6    +      -       -      +
     75D  VAL*     3.8     8.3    -      -       +      +
     77D  ARG*     1.3    73.4    -      -       -      +
     79D  HIS*     1.3    57.0    +      -       -      +
     81D  LEU*     3.3     0.4    +      -       -      -
     82D  ALA*     2.8    37.0    +      -       -      +
    105D  GLU*     3.3    28.5    -      -       -      +
    106D  HIS      5.9     0.2    -      -       -      -
    108D  MET*     3.0    47.7    +      -       +      +
    110D  GLU*     4.0    16.8    -      -       -      +
    113D  GLU*     3.1    35.2    +      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 79 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13D  ARG*     4.0    14.0    +      -       -      -
     75D  VAL      3.0    12.5    +      -       -      +
     76D  MET*     3.3     9.8    +      -       -      +
     78D  LYS*     1.3    75.2    -      -       -      +
     80D  ARG*     1.3    73.6    +      -       +      +
     82D  ALA*     4.4     0.7    -      -       -      -
     83D  GLU*     2.6    36.3    +      -       -      +
     98D  HIS*     3.1    24.6    -      +       -      -
    101D  ALA*     3.4    22.2    +      -       +      +
    102D  CYS      3.9     2.0    +      -       -      -
    105D  GLU*     3.2    33.3    +      -       -      +
   1001D   NI      2.0    46.2    -      -       +      +
   2001D  ACT      3.1     2.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 80 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17D  ASP*     4.6     3.4    +      -       -      -
     20D  GLU*     3.0    40.8    +      -       -      -
     76D  MET*     3.1    51.4    +      -       -      +
     77D  ARG      4.3     0.4    -      -       -      +
     79D  HIS*     1.3    81.2    -      -       +      +
     81D  LEU*     1.3    62.0    +      -       -      +
     82D  ALA      3.2     0.9    -      -       -      -
     83D  GLU*     3.1    12.3    +      -       -      +
     84D  ARG*     2.9    31.2    +      -       -      +
    126D  SER*     3.6    20.5    -      -       -      -
    130D  ASN*     3.5    20.8    -      -       -      +
    131D  PRO*     2.7    36.9    +      -       -      +
    132D  ILE*     3.6    22.4    -      -       +      +
    133D  PRO*     4.5     1.6    -      -       -      +
   2001D  ACT      3.8    17.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 81 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77D  ARG*     3.0    29.9    +      -       +      +
     78D  LYS*     3.9     3.1    -      -       -      +
     80D  ARG*     1.3    72.7    -      -       -      +
     82D  ALA*     1.3    65.4    +      -       -      +
     84D  ARG*     3.3     4.3    +      -       +      +
     85D  LEU*     3.0    24.4    +      -       -      +
    108D  MET*     4.9     1.6    -      -       +      -
    113D  GLU*     3.8    44.9    -      -       +      +
    116D  LEU*     3.9    18.0    -      -       +      +
    117D  VAL*     4.6    13.0    -      -       +      +
    120D  LEU*     3.9     7.6    -      -       +      +
    123D  PRO*     3.8    30.1    -      -       +      -
    132D  ILE*     4.1    17.9    -      -       +      -
    135D  LEU*     4.9     3.4    -      -       +      -
    138D  LEU*     4.8     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 82 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78D  LYS      2.8    19.7    +      -       -      +
     79D  HIS*     3.6     6.7    -      -       -      +
     81D  LEU*     1.3    76.9    -      -       -      +
     83D  GLU*     1.3    55.0    +      -       -      +
     85D  LEU*     3.4     6.4    +      -       -      +
     86D  LEU*     2.9    37.3    +      -       +      +
    101D  ALA*     3.8    13.5    -      -       +      -
    104D  TRP*     4.2    24.0    -      -       +      -
    105D  GLU      5.1     0.4    -      -       -      +
    108D  MET*     4.1    15.3    -      -       -      -
    116D  LEU*     4.9     2.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 83 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     79D  HIS*     2.6    24.5    +      -       -      +
     80D  ARG*     3.1    11.0    +      -       -      +
     82D  ALA*     1.3    73.2    -      -       -      +
     84D  ARG*     1.3    67.8    +      -       -      +
     86D  LEU*     3.2     2.9    +      -       -      +
     87D  VAL*     3.1    27.0    +      -       -      +
     97D  VAL*     3.5    24.2    -      -       +      +
     98D  HIS*     3.0     6.2    +      -       -      -
    101D  ALA*     3.5    10.1    -      -       +      -
    126D  SER*     3.5    10.4    -      -       -      -
    127D  PRO*     3.6    12.1    -      -       +      -
    128D  PHE*     3.3    17.2    -      -       -      -
   1001D   NI      1.9    39.9    -      -       -      +
   2001D  ACT      3.1    14.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 84 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80D  ARG      2.9    15.5    +      -       -      +
     81D  LEU*     3.5     6.3    -      -       -      +
     83D  GLU*     1.3    75.0    -      -       -      +
     85D  LEU*     1.3    59.2    +      -       -      +
     87D  VAL*     3.2     1.4    +      -       -      +
     88D  ASP*     2.8    73.5    +      -       -      +
    120D  LEU*     3.4    20.2    -      -       +      -
    123D  PRO*     3.4    28.2    -      -       +      +
    125D  THR*     2.8    48.5    +      -       -      +
    126D  SER      3.5    13.3    +      -       -      -
    127D  PRO*     3.4    26.1    -      -       +      +
    132D  ILE*     4.3     4.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 85 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     85C  LEU*     4.8     7.0    -      -       +      -
     89C  VAL*     5.1     3.1    -      -       +      -
     90C  ILE*     4.3    21.8    -      -       +      -
    104C  TRP*     5.0     2.7    -      -       +      -
     81D  LEU      3.0    17.2    +      -       -      +
     82D  ALA*     3.7     5.2    -      -       -      +
     84D  ARG*     1.3    75.4    -      -       -      +
     86D  LEU*     1.3    58.0    +      -       -      +
     89D  VAL*     3.2    31.4    +      -       +      +
     90D  ILE*     3.0    36.6    +      -       +      +
    104D  TRP*     4.0    28.5    -      -       +      -
    116D  LEU*     4.1    29.8    -      -       +      -
    119D  VAL*     6.1     2.2    -      -       +      -
    120D  LEU*     3.8    13.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 86 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112C  VAL*     4.3    11.7    -      -       +      -
     82D  ALA*     2.9    27.6    +      -       +      +
     83D  GLU      3.2     4.7    +      -       -      +
     85D  LEU*     1.3    76.5    -      -       +      +
     87D  VAL*     1.3    59.8    +      -       -      +
     90D  ILE*     3.7    26.8    -      -       +      -
     91D  GLY      3.0     7.8    +      -       -      -
     92D  LEU*     3.0    34.1    +      -       +      +
     97D  VAL*     3.5    35.9    -      -       +      +
    100D  GLU*     3.6    20.9    -      -       +      -
    101D  ALA*     4.0    10.8    -      -       +      +
    104D  TRP*     3.7    26.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 87 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     83D  GLU      3.1    15.2    +      -       -      +
     84D  ARG*     3.9     1.8    -      -       -      +
     86D  LEU*     1.3    76.6    -      -       -      +
     88D  ASP*     1.3    75.9    +      -       -      +
     89D  VAL      3.3     0.7    +      -       -      -
     91D  GLY*     3.5    17.7    +      -       -      -
     92D  LEU      4.8     7.9    -      -       -      +
     94D  TRP*     3.9    27.6    -      -       +      -
     97D  VAL*     3.9    25.8    -      -       +      -
    127D  PRO*     3.5    23.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 88 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84D  ARG*     2.8    61.2    +      -       -      +
     87D  VAL*     1.3    82.4    -      -       -      +
     89D  VAL*     1.3    62.0    +      -       +      +
    120D  LEU*     4.4    20.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 89 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     85C  LEU*     5.3     1.6    -      -       +      -
     89C  VAL*     3.9    28.0    -      -       +      -
    115C  ARG*     5.1     0.5    +      -       -      -
    119C  VAL*     3.8    23.3    -      -       +      +
     85D  LEU*     3.2    23.4    +      -       +      +
     88D  ASP*     1.3    82.9    -      -       +      +
     90D  ILE*     1.3    73.1    +      -       +      +
     91D  GLY*     3.2     3.1    +      -       -      -
    119D  VAL*     5.2     7.2    -      -       +      +
    120D  LEU*     4.0    25.1    -      -       +      -
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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