Contacts of the helix formed by residues 40 - 64 (chain A) in PDB entry 3GIA


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 ASN 40 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  ALA*     2.9    15.7    +      -       -      +
     39A  ARG*     1.3    76.6    -      -       -      +
     41A  LEU*     1.3    58.0    +      -       -      +
     43A  GLU*     3.0    32.4    +      -       -      +
     44A  THR      3.0     9.5    +      -       -      -
    180A  PRO*     3.6     9.9    -      -       -      +
    181A  ASP*     2.7    51.7    +      -       -      +
    186A  ALA*     3.0    27.4    +      -       -      +
    187A  VAL*     3.8     3.4    -      -       -      +
    190A  MET*     3.4    23.3    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 41 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  PHE*     3.5    44.2    -      -       +      +
     33A  GLY*     3.7    28.5    -      -       -      +
     34A  ALA*     4.2    12.8    -      -       -      +
     37A  ALA*     3.8    10.1    +      -       +      -
     38A  GLY      3.3    15.5    +      -       -      +
     40A  ASN*     1.3    74.0    -      -       -      +
     42A  PRO*     1.4    70.8    -      -       +      +
     44A  THR*     3.0    22.9    +      -       +      -
     45A  PHE*     3.1    30.4    +      -       +      -
    197A  PHE*     4.0    11.0    -      -       +      -
    240A  ALA*     4.0     4.7    -      -       +      -
    244A  ILE*     3.8     7.6    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with PRO 42 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  ARG      3.3    17.0    -      -       -      +
     40A  ASN      3.4     1.6    -      -       -      -
     41A  LEU*     1.4    95.4    -      -       +      +
     43A  GLU*     1.3    70.1    +      -       -      +
     45A  PHE*     3.5     7.7    +      -       +      +
     46A  ILE*     3.3    28.4    +      -       +      +
    178A  VAL      5.5     4.3    -      -       -      +
    237A  VAL*     3.8    12.2    -      -       +      +
    240A  ALA*     3.8    23.1    -      -       +      -
    241A  ILE*     3.9    30.1    -      -       +      +
    244A  ILE*     3.8    10.3    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 43 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  ARG      3.7     4.7    -      -       -      +
     40A  ASN*     3.0    30.0    +      -       +      +
     42A  PRO*     1.3    83.3    -      -       -      +
     44A  THR*     1.3    60.3    +      -       -      +
     46A  ILE*     3.4    15.9    +      -       +      +
     47A  LEU*     3.0    29.3    +      -       -      +
    178A  VAL      4.5     6.1    -      -       -      +
    180A  PRO*     3.5    37.0    -      -       +      +
    190A  MET*     4.0    21.0    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 44 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  ALA*     3.4    14.5    -      -       -      +
     40A  ASN      3.0     4.2    +      -       -      -
     41A  LEU*     3.2    19.1    -      -       +      +
     43A  GLU*     1.3    73.4    -      -       -      +
     45A  PHE*     1.3    60.3    +      -       -      +
     47A  LEU*     3.3     3.0    +      -       -      +
     48A  SER*     2.9    33.1    +      -       -      -
    190A  MET*     2.9    33.2    +      -       -      +
    193A  ALA*     3.7    12.3    -      -       +      +
    194A  SER*     3.5    28.0    -      -       -      +
    197A  PHE*     4.1    15.3    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with PHE 45 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  SER*     4.2     9.4    -      -       -      -
     26A  ILE*     4.8     1.1    -      -       +      -
     30A  PHE*     4.1    16.8    -      +       -      -
     41A  LEU*     3.1    44.3    +      -       +      -
     42A  PRO*     3.7     7.6    -      -       +      +
     44A  THR*     1.3    75.6    -      -       -      +
     46A  ILE*     1.3    55.9    +      -       -      +
     48A  SER*     3.6     3.0    +      -       -      -
     49A  GLY      2.9    14.9    +      -       -      -
    197A  PHE*     3.5    36.6    -      +       +      -
    200A  SER*     3.9    12.3    -      -       -      -
    201A  TYR*     2.7    25.5    +      +       -      +
    233A  MET*     5.1     0.9    -      -       -      -
    236A  TYR*     3.5    60.1    -      +       +      -
    237A  VAL*     4.4     7.0    -      -       +      -
    240A  ALA*     4.1     7.0    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 46 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42A  PRO*     3.3    19.6    +      -       +      +
     43A  GLU*     3.6    17.9    -      -       +      +
     44A  THR      3.3     0.6    -      -       -      -
     45A  PHE*     1.3    75.1    -      -       -      +
     47A  LEU*     1.3    59.6    +      -       -      +
     49A  GLY*     3.0     3.6    +      -       -      -
     50A  ILE*     2.9    43.6    +      -       +      +
    233A  MET*     4.5    17.4    -      -       +      +
    237A  VAL*     3.7    25.8    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 47 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43A  GLU      3.0    17.3    +      -       -      +
     44A  THR*     3.3     4.7    +      -       -      +
     46A  ILE*     1.3    78.2    -      -       -      +
     48A  SER*     1.3    61.1    +      -       -      +
     50A  ILE*     3.0    27.4    +      -       +      +
     51A  TYR*     3.2    51.1    +      -       +      +
    190A  MET*     3.7    26.9    -      -       +      -
    191A  ILE*     4.1    16.6    -      -       +      -
    194A  SER*     3.8    11.2    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 48 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     44A  THR      2.9    18.7    +      -       -      -
     45A  PHE*     3.8     2.9    -      -       -      -
     47A  LEU*     1.3    76.2    -      -       -      +
     49A  GLY*     1.3    57.3    +      -       -      +
     51A  TYR*     3.3    15.3    +      -       -      +
     52A  ALA*     3.0    26.0    +      -       -      +
    194A  SER*     2.8    28.3    +      -       -      -
    197A  PHE*     3.3    29.0    +      -       -      +
    198A  PHE*     4.4     4.3    -      -       -      -
    201A  TYR*     3.6    14.0    -      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLY 49 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  PHE      2.9    11.8    +      -       -      -
     46A  ILE      3.0     6.4    +      -       -      -
     48A  SER*     1.3    74.0    -      -       -      +
     50A  ILE*     1.3    59.2    +      -       -      +
     52A  ALA*     3.4     3.1    +      -       -      +
     53A  LEU*     3.0    34.8    +      -       -      +
    201A  TYR*     3.4    24.0    -      -       -      -
    233A  MET*     3.8    14.9    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 50 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  ILE*     2.9    30.6    +      -       +      +
     47A  LEU*     3.0    19.9    +      -       +      +
     49A  GLY*     1.3    76.3    -      -       -      +
     51A  TYR*     1.3    69.2    +      -       +      +
     53A  LEU*     3.2    16.0    +      -       +      +
     54A  LEU*     3.0    37.0    +      -       +      +
    233A  MET*     5.5     4.0    -      -       -      -
    378A  PHE*     6.3     1.1    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with TYR 51 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47A  LEU*     3.3    35.2    -      -       +      +
     48A  SER*     3.4    17.5    -      -       -      +
     50A  ILE*     1.3    78.5    -      -       +      +
     52A  ALA*     1.3    60.8    +      -       -      +
     54A  LEU*     3.3     9.6    +      -       -      +
     55A  VAL*     3.1    27.4    +      -       -      +
    191A  ILE*     4.7     6.2    +      -       -      +
    194A  SER*     3.0    44.8    +      -       -      -
    198A  PHE*     3.4    35.4    -      +       +      -
    382A  VAL*     3.7    23.6    -      -       +      -
    383A  VAL*     4.8     2.2    -      -       +      +
    386A  VAL*     3.6    29.1    -      -       +      +
    389A  LEU*     5.8     0.7    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 52 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48A  SER      3.0     8.6    +      -       -      +
     49A  GLY      3.5     8.5    -      -       -      +
     50A  ILE      3.2     0.2    -      -       -      -
     51A  TYR*     1.3    76.9    -      -       -      +
     53A  LEU*     1.3    52.5    +      -       -      +
     55A  VAL*     3.4     0.7    +      -       -      -
     56A  ALA*     2.8    34.3    +      -       -      +
    198A  PHE*     3.9     9.8    -      -       +      -
    201A  TYR*     3.4    43.7    -      -       +      -
    204A  PHE*     3.3    12.0    -      -       +      -
    229A  ILE*     4.3    10.1    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 53 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  GLY      3.0    22.2    +      -       -      +
     50A  ILE*     3.2    15.9    +      -       +      +
     52A  ALA*     1.3    73.9    -      -       -      +
     54A  LEU*     1.3    61.5    +      -       -      +
     56A  ALA*     3.3     5.6    +      -       +      +
     57A  TYR*     3.0    26.9    +      -       -      +
    226A  PHE*     3.7    36.1    -      -       +      -
    229A  ILE*     3.9    24.5    -      -       +      -
    230A  LEU*     4.5     9.2    -      -       +      -
    233A  MET*     3.8    18.2    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 54 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50A  ILE*     3.0    30.1    +      -       +      +
     51A  TYR*     3.5    10.1    -      -       -      +
     53A  LEU*     1.3    77.5    -      -       +      +
     55A  VAL*     1.3    61.8    +      -       +      +
     57A  TYR*     3.3    20.1    -      -       +      +
     58A  SER*     3.9     4.0    +      -       -      -
    375A  ILE*     4.9     9.6    -      -       +      -
    378A  PHE*     3.9    24.9    -      -       +      -
    379A  SER*     3.4    35.2    +      -       -      +
    382A  VAL*     3.8    42.0    -      -       +      -
    383A  VAL*     5.5     1.6    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 55 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51A  TYR      3.1    14.1    +      -       -      +
     52A  ALA*     3.6     7.6    -      -       -      +
     54A  LEU*     1.3    73.7    -      -       -      +
     56A  ALA*     1.3    63.8    +      -       -      +
     58A  SER*     3.0    15.9    +      -       -      -
     59A  TYR*     3.1    38.0    +      -       +      -
    198A  PHE*     3.7    20.9    -      -       +      -
    204A  PHE*     3.6    13.5    -      -       +      -
    355A  TYR*     3.8    26.7    -      -       +      +
    358A  VAL*     5.8     0.2    -      -       +      -
    359A  ILE*     4.1    12.8    -      -       +      -
    383A  VAL*     3.8    16.8    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 56 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  ALA      2.8    21.2    +      -       -      +
     53A  LEU*     3.3    14.3    +      -       +      +
     55A  VAL*     1.3    70.6    -      -       -      +
     57A  TYR*     1.3    53.1    +      -       -      +
     59A  TYR*     4.3     2.0    -      -       -      -
     60A  THR*     2.6    46.0    +      -       +      +
    204A  PHE*     3.7    12.8    -      -       +      -
    225A  ILE*     3.9     8.7    -      -       +      -
    226A  PHE*     5.6     4.9    -      -       +      -
    229A  ILE*     3.8    20.9    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with TYR 57 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53A  LEU      3.0    11.7    +      -       -      +
     54A  LEU*     3.3    15.5    -      -       -      +
     56A  ALA*     1.3    75.2    -      -       -      +
     58A  SER*     1.3    60.8    +      -       -      +
     60A  THR*     3.2    15.5    +      -       -      -
     61A  LYS*     3.2    41.4    -      -       -      +
    362A  HIS*     3.8    22.0    -      +       -      -
    371A  GLY*     3.1     9.7    -      -       -      -
    372A  ARG*     2.7    34.7    +      -       -      +
    375A  ILE*     3.7    41.5    -      -       +      +
    376A  VAL*     4.0    12.3    -      -       +      -
    379A  SER*     5.1     0.7    -      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 58 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54A  LEU      3.9     2.6    +      -       -      -
     55A  VAL      3.0     9.6    +      -       -      -
     57A  TYR*     1.3    78.8    -      -       -      +
     59A  TYR*     1.3    64.9    +      -       -      +
     61A  LYS*     3.3     1.7    +      -       -      +
     62A  LEU*     3.0    31.5    +      -       -      +
    358A  VAL*     4.3     7.4    -      -       -      -
    359A  ILE*     3.7    30.9    -      -       -      +
    362A  HIS*     2.8    37.5    +      -       -      +
    376A  VAL*     4.6     3.1    -      -       -      +
    379A  SER*     5.5     0.9    -      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with TYR 59 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55A  VAL*     3.1    40.9    +      -       +      +
     56A  ALA*     4.0     5.2    -      -       -      +
     58A  SER*     1.3    75.8    -      -       -      +
     60A  THR*     1.3    58.0    +      -       -      +
     62A  LEU*     4.1     3.7    -      -       -      +
     63A  GLY*     2.8    28.1    +      -       -      -
     72A  PRO*     3.9     9.1    -      -       +      +
     75A  PHE*     4.1    17.6    -      +       -      -
     93A  LEU*     5.9     0.2    -      -       -      +
    204A  PHE*     3.5    38.7    -      +       +      +
    205A  GLY*     6.0     0.2    -      -       -      -
    208A  THR*     3.7    33.4    -      -       +      -
    221A  VAL*     5.3     1.2    -      -       -      +
    225A  ILE*     4.0    11.4    -      -       +      +
    354A  ILE*     3.8    10.0    -      -       -      +
    355A  TYR*     3.7    21.3    -      +       -      -
    358A  VAL*     3.8    34.1    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 60 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56A  ALA*     2.6    30.7    +      -       +      +
     57A  TYR*     3.2    12.6    +      -       -      -
     59A  TYR*     1.3    75.2    -      -       -      +
     61A  LYS*     1.3    68.1    +      -       -      +
     64A  ALA*     3.3    24.3    +      -       -      +
    222A  PRO*     3.6    46.4    -      -       +      +
    225A  ILE*     4.2    15.3    -      -       +      -
    226A  PHE*     5.0     6.5    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 61 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57A  TYR*     3.2    36.0    +      -       +      +
     58A  SER      3.3     2.5    +      -       -      +
     60A  THR*     1.3    84.7    +      -       -      +
     62A  LEU*     1.3    64.0    +      -       -      +
     64A  ALA*     3.6     8.7    +      -       -      +
     65A  LYS*     3.8     9.2    -      -       -      +
    362A  HIS*     3.7    26.9    -      -       +      +
    369A  VAL*     3.7    34.8    -      -       +      +
    370A  GLY*     4.0     6.3    -      -       -      -
    371A  GLY*     3.9    19.3    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 62 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     58A  SER      3.0    20.0    +      -       -      +
     61A  LYS*     1.3    79.1    -      -       -      +
     63A  GLY*     1.3    51.6    +      -       -      +
     65A  LYS*     3.1     4.9    +      -       -      +
     66A  ILE*     2.8    49.4    +      -       +      +
     75A  PHE*     3.7    33.7    -      -       +      -
    358A  VAL*     3.6    39.7    -      -       +      +
    361A  SER      4.6     0.2    -      -       -      -
    362A  HIS*     3.9    22.4    -      -       +      +
    365A  LEU*     4.0    26.9    -      -       +      -
    369A  VAL*     4.1    15.0    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLY 63 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  TYR      2.8    21.3    +      -       -      -
     60A  THR      4.2     0.9    -      -       -      -
     62A  LEU*     1.3    69.6    -      -       -      +
     64A  ALA*     1.3    60.7    +      -       -      +
     65A  LYS      3.2     2.4    +      -       -      -
     66A  ILE      3.6    17.8    +      -       -      +
     67A  VAL*     4.5     2.4    -      -       -      +
     75A  PHE*     3.9     9.8    -      -       -      -
    217A  PRO      4.1     4.9    -      -       -      +
    218A  LYS*     3.8    15.2    -      -       -      +
    221A  VAL*     4.7    13.9    -      -       -      +
    222A  PRO*     4.3     6.9    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 64 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60A  THR      3.3    19.2    +      -       -      +
     61A  LYS*     3.9     6.5    -      -       -      +
     62A  LEU      3.2     0.8    -      -       -      -
     63A  GLY*     1.3    78.0    -      -       -      +
     65A  LYS*     1.3    68.1    +      -       +      +
    218A  LYS*     3.3    42.6    -      -       -      +
    222A  PRO*     4.1     4.2    -      -       +      +
----------------------------------------------------------
 Back to top of page


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