Contacts of the helix formed by residues 54 - 77 (chain A) in PDB entry 2I2X


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 SER 54 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51A  ALA      3.5     5.7    -      -       -      +
     52A  GLY      4.4     0.3    -      -       -      -
     53A  ALA*     1.3    78.6    -      -       -      +
     55A  LYS*     1.3    64.7    +      -       -      +
     56A  GLU*     3.5    15.7    +      -       -      +
     57A  LYS*     3.3    30.4    +      -       -      +
     58A  LEU*     3.2    18.0    +      -       -      +
     97A  TRP*     4.1     7.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 55 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54A  SER*     1.3    73.1    -      -       -      +
     56A  GLU*     1.3    82.0    +      -       -      +
     58A  LEU*     3.3     3.2    +      -       +      +
     59A  ILE*     3.0    41.1    +      -       +      +
     96A  SER*     5.1     2.2    +      -       -      -
     97A  TRP*     3.4    68.1    -      -       +      +
    100A  GLU*     2.7    43.0    +      -       -      +
    101A  VAL*     6.3     0.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 56 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54A  SER*     3.1    12.4    -      -       -      +
     55A  LYS*     1.3   111.6    +      -       -      +
     57A  LYS*     1.3    61.0    +      -       +      +
     59A  ILE*     3.6    10.2    +      -       +      +
     60A  LYS*     2.9    29.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 57 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50A  GLU      4.3     6.0    +      -       -      +
     51A  ALA*     3.6    20.8    -      -       -      +
     53A  ALA*     3.9    25.5    -      -       +      +
     54A  SER*     3.3    18.9    +      -       -      +
     56A  GLU*     1.3    77.2    -      -       +      +
     58A  LEU*     1.3    57.0    +      -       -      +
     60A  LYS*     3.4     7.6    +      -       -      +
     61A  GLU*     2.9    29.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 58 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47A  PRO*     3.8    31.2    -      -       +      -
     51A  ALA*     3.1    27.2    +      -       +      +
     52A  GLY*     4.4     3.6    -      -       -      +
     54A  SER      3.2     5.7    +      -       -      +
     55A  LYS*     3.4     9.0    -      -       +      +
     56A  GLU      3.3     0.2    -      -       -      -
     57A  LYS*     1.3    74.1    -      -       -      +
     59A  ILE*     1.3    65.7    +      -       +      +
     61A  GLU*     3.2     3.5    +      -       -      +
     62A  TYR*     3.1    42.6    +      -       +      -
     88A  VAL*     4.0    14.1    -      -       +      -
     90A  GLN*     4.3     4.9    -      -       +      +
     91A  MET*     3.9    26.5    -      -       +      -
     97A  TRP*     4.0    23.8    -      -       +      -
    101A  VAL*     4.8     4.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 59 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55A  LYS*     3.0    38.2    +      -       +      +
     56A  GLU*     3.8     9.9    -      -       +      +
     58A  LEU*     1.3    74.6    -      -       +      +
     60A  LYS*     1.3    59.2    +      -       -      +
     62A  TYR*     3.4     3.7    +      -       -      +
     63A  GLU*     2.9    37.2    +      -       -      +
    100A  GLU*     3.8    33.2    -      -       +      +
    101A  VAL*     4.0    27.8    -      -       +      +
    104A  ALA*     3.9    23.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 60 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56A  GLU      2.9    19.7    +      -       -      +
     57A  LYS*     3.4     9.2    -      -       -      +
     58A  LEU      3.1     0.2    -      -       -      -
     59A  ILE*     1.3    74.2    -      -       -      +
     61A  GLU*     1.3    65.6    +      -       -      +
     63A  GLU*     3.1    25.4    +      -       +      +
     64A  ARG*     3.0    46.6    +      -       -      +
    257D  LYS*     3.9    25.7    +      -       -      +
    258D  HIS*     3.2    44.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 61 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47A  PRO*     3.6    22.8    -      -       +      +
     48A  ARG*     2.7    66.1    +      -       -      +
     51A  ALA*     3.7    15.1    -      -       +      +
     57A  LYS      2.9    16.2    +      -       -      +
     58A  LEU      3.2     5.6    +      -       -      +
     60A  LYS*     1.3    74.7    -      -       -      +
     62A  TYR*     1.3    59.0    +      -       -      +
     64A  ARG*     3.0    15.9    +      -       -      +
     65A  ILE*     2.9    34.4    +      -       +      +
    317A  TYR*     3.6    15.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 62 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  TYR*     3.6    30.8    +      +       -      -
     47A  PRO*     3.4    29.3    -      -       +      +
     58A  LEU*     3.1    40.5    +      -       +      +
     59A  ILE      3.8     3.8    -      -       -      +
     61A  GLU*     1.3    74.1    -      -       +      +
     63A  GLU*     1.3    57.7    +      -       +      +
     65A  ILE*     3.3     9.5    +      -       +      +
     66A  THR*     2.6    39.1    +      -       -      -
     85A  THR*     3.5    26.4    -      -       +      +
     86A  GLU      4.2     9.2    +      -       -      -
     88A  VAL*     4.2     2.6    -      -       -      +
     91A  MET*     3.5    33.1    -      -       +      -
    101A  VAL*     3.4    28.9    -      -       +      -
    104A  ALA*     6.3     0.4    -      -       +      -
    105A  GLN*     4.3     9.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 63 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  ILE*     2.9    26.2    +      -       -      +
     60A  LYS*     3.1    29.5    +      -       +      +
     62A  TYR*     1.3    74.9    -      -       -      +
     64A  ARG*     1.3    64.1    +      -       +      +
     66A  THR*     4.4     0.7    -      -       -      -
     67A  THR*     3.0    30.1    +      -       -      -
    104A  ALA*     3.8    30.1    -      -       +      +
    105A  GLN*     5.9     0.4    -      -       -      -
    108A  ILE*     3.8    25.2    -      -       +      +
    258D  HIS      6.0     1.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 64 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48A  ARG*     4.3    10.4    -      -       -      +
     60A  LYS*     3.0    38.4    +      -       -      +
     61A  GLU*     3.0    16.0    +      -       -      +
     63A  GLU*     1.3    76.5    -      -       +      +
     65A  ILE*     1.3    57.9    +      -       -      +
     67A  THR*     3.5     3.4    +      -       -      -
     68A  ASP*     2.9    37.3    +      -       -      +
    317A  TYR*     3.5    27.1    -      -       +      +
    216D  GLN*     4.0    23.4    +      -       -      +
    217D  ASP*     3.6    32.9    +      -       -      -
    257D  LYS*     5.7     0.4    -      -       -      +
    258D  HIS*     3.0    34.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 65 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  TYR*     3.6    55.6    -      -       +      -
     47A  PRO      4.7     5.4    -      -       -      -
     61A  GLU*     2.9    27.4    +      -       +      +
     62A  TYR*     3.6    22.4    -      -       +      +
     63A  GLU      3.3     0.2    -      -       -      -
     64A  ARG*     1.3    75.7    -      -       -      +
     66A  THR*     1.3    64.8    +      -       -      +
     68A  ASP*     3.2     3.1    +      -       -      +
     69A  VAL*     3.0    31.7    +      -       +      +
     83A  LEU*     5.1     0.2    -      -       +      -
    317A  TYR*     3.6    43.7    -      -       +      -
    326A  VAL*     3.8    10.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 66 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62A  TYR      2.6    22.4    +      -       -      -
     63A  GLU      3.9     2.7    -      -       -      -
     65A  ILE*     1.3    74.1    -      -       -      +
     67A  THR*     1.3    65.3    +      -       -      +
     68A  ASP      3.4     0.2    +      -       -      -
     69A  VAL*     3.4     1.0    +      -       -      +
     70A  MET*     3.0    31.1    +      -       +      +
     83A  LEU*     3.8    22.6    -      -       +      +
    105A  GLN*     3.2    47.4    +      -       -      +
    108A  ILE*     3.8    20.2    -      -       +      -
    109A  MET*     4.0    12.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 67 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63A  GLU*     3.0    18.2    +      -       -      +
     64A  ARG*     3.9     4.7    -      -       -      -
     66A  THR*     1.3    77.7    -      -       -      +
     68A  ASP*     1.3    69.2    +      -       -      +
     70A  MET      4.0     0.2    -      -       -      -
     71A  GLU*     3.0    26.6    +      -       +      +
    108A  ILE*     3.6    25.2    -      -       -      +
    112A  TYR*     4.1    17.5    +      -       +      +
    258D  HIS      5.6     5.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 68 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64A  ARG*     2.9    22.9    +      -       -      +
     65A  ILE      3.2     4.7    +      -       -      +
     67A  THR*     1.3    81.8    -      -       -      +
     69A  VAL*     1.3    56.3    +      -       -      +
     71A  GLU*     3.9     1.9    -      -       -      +
     72A  ARG      3.1    17.5    +      -       -      -
    317A  TYR*     2.4    24.9    +      -       -      -
    324A  THR*     3.1    30.3    +      -       +      +
    326A  VAL*     3.8     2.2    -      -       +      -
    327A  GLN*     3.0    38.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 69 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43A  ILE*     3.8    18.4    -      -       +      -
     65A  ILE*     3.0    21.7    +      -       +      +
     66A  THR      3.7     3.8    -      -       -      +
     68A  ASP*     1.3    73.7    -      -       -      +
     70A  MET*     1.3    67.8    +      -       -      +
     72A  ARG*     3.2     3.6    +      -       -      +
     73A  MET*     3.0    26.2    +      -       +      +
     81A  ILE*     3.6    32.5    -      -       +      -
     83A  LEU*     4.2    16.4    -      -       +      -
    326A  VAL*     3.8    27.8    -      -       +      +
    327A  GLN*     4.8     1.1    -      -       -      -
    330A  SER*     4.6    11.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET 70 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66A  THR*     3.0    32.1    +      -       +      +
     67A  THR      4.1     0.2    -      -       -      +
     69A  VAL*     1.3    76.7    -      -       -      +
     71A  GLU*     1.3    65.2    +      -       -      +
     73A  MET*     3.2     4.4    +      -       -      +
     74A  VAL*     3.2    25.8    +      -       -      +
     81A  ILE*     4.1     9.0    -      -       +      -
     83A  LEU*     3.8    27.1    -      -       +      -
    108A  ILE*     4.4     2.9    -      -       +      -
    109A  MET*     4.3    11.7    -      -       +      +
    112A  TYR*     3.5    41.3    -      -       +      -
    118A  ILE*     3.7    39.7    -      -       +      -
    120A  CYS*     4.1    17.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 71 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67A  THR*     3.0    22.1    +      -       +      +
     68A  ASP*     3.9     5.8    -      -       -      +
     70A  MET*     1.3    78.6    -      -       -      +
     72A  ARG*     1.3    63.9    +      -       -      +
     74A  VAL*     3.2     6.5    +      -       -      +
     75A  GLN*     3.0    55.0    +      -       +      +
    112A  TYR*     2.8    34.9    +      -       -      +
    116A  TYR*     4.7     5.4    +      -       -      -
    327A  GLN*     4.8     6.1    -      -       -      +
    234C  LEU*     5.1     1.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 72 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68A  ASP      3.1    19.1    +      -       -      +
     69A  VAL      3.2     4.2    +      -       -      +
     71A  GLU*     1.3    77.1    -      -       -      +
     73A  MET*     1.3    64.8    +      -       +      +
     75A  GLN*     3.1     8.9    +      -       -      +
     76A  VAL*     3.1    26.5    +      -       +      +
     78A  PHE*     5.8     0.7    -      -       +      -
    322A  GLY      3.2    27.5    +      -       -      -
    323A  GLY*     4.6     0.8    -      -       -      -
    327A  GLN*     3.6    63.2    +      -       +      +
    328A  CYS*     4.1     7.3    -      -       -      +
    330A  SER*     4.6     5.6    -      -       -      +
    331A  GLU*     3.0    34.4    +      -       +      +
    292C  THR*     4.3     4.2    +      -       -      -
    296C  SER*     3.7    25.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 73 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41A  PRO*     3.8     1.8    -      -       +      -
     69A  VAL*     3.0    21.5    +      -       +      +
     70A  MET*     3.2     4.0    +      -       -      +
     72A  ARG*     1.3    78.6    -      -       -      +
     74A  VAL*     1.3    58.5    +      -       -      +
     76A  VAL*     3.4     0.9    +      -       -      -
     77A  GLY      3.1     7.1    +      -       -      -
     78A  PHE*     2.9    63.3    +      -       +      +
     80A  ALA      3.2    27.4    -      -       -      +
     81A  ILE*     3.5    33.0    -      -       +      -
    118A  ILE*     3.6    18.8    -      -       +      -
    330A  SER*     4.4    19.7    -      -       -      +
    331A  GLU*     5.2     0.4    -      -       -      -
    334A  ALA*     3.7    17.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 74 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70A  MET      3.2    13.2    +      -       -      +
     71A  GLU*     3.3    17.0    -      -       -      +
     73A  MET*     1.3    74.4    -      -       -      +
     75A  GLN*     1.3    64.2    +      -       -      +
     76A  VAL      3.3     0.5    +      -       -      -
     77A  GLY*     3.4     2.3    +      -       -      -
    112A  TYR*     4.1    13.0    -      -       +      -
    116A  TYR*     3.8    40.2    -      -       +      +
    118A  ILE*     4.2    20.0    -      -       +      -
    233C  LEU*     4.1     4.9    -      -       -      +
    234C  LEU*     3.5    26.1    -      -       +      +
     16D  TYR*     3.3    35.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 75 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71A  GLU*     3.0    47.8    +      -       +      +
     72A  ARG*     3.1    12.1    +      -       -      +
     74A  VAL*     1.3    78.7    -      -       -      +
     76A  VAL*     1.3    63.2    +      -       +      +
    232C  GLY*     3.2    20.8    -      -       -      -
    233C  LEU*     3.0    29.1    +      -       -      +
    234C  LEU*     3.0    44.5    +      -       +      +
    235C  ASN*     3.5    17.9    +      -       -      +
    298C  VAL*     5.2     1.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 76 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72A  ARG*     3.1    22.9    +      -       +      +
     75A  GLN*     1.3    82.0    -      -       +      +
     77A  GLY*     1.3    59.0    +      -       -      +
     78A  PHE*     3.4    31.4    -      -       +      -
    331A  GLU*     3.5     9.9    -      -       -      +
    335A  TYR*     3.5    27.1    -      -       +      +
    233C  LEU*     3.7     5.2    -      -       -      -
    296C  SER*     3.4    24.9    -      -       -      +
    297C  ASP      3.6     9.0    -      -       -      +
    298C  VAL*     4.6     4.7    -      -       +      +
    363C  ARG*     3.1    26.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 77 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  MET      3.1     2.6    +      -       -      -
     74A  VAL      3.4     3.8    +      -       -      -
     75A  GLN      3.4     0.2    -      -       -      -
     76A  VAL*     1.3    80.9    -      -       -      +
     78A  PHE*     1.3    64.5    +      -       -      +
     79A  PRO      3.5     0.7    -      -       -      -
    233C  LEU*     3.5     9.5    -      -       -      +
    363C  ARG*     4.0     5.4    -      -       -      -
     13D  LEU*     3.5     7.7    -      -       -      +
     14D  THR      3.0    44.4    +      -       -      -
     16D  TYR*     3.7     8.7    -      -       -      -
----------------------------------------------------------
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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