Contacts of the helix formed by residues 315 - 338 (chain A) in PDB entry 3A3K


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 315 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  ARG*     5.0    10.6    +      -       -      -
    290A  TYR*     3.5    12.8    +      -       -      +
    293A  PHE*     4.7     1.7    -      -       -      -
    294A  LEU*     3.8    21.3    -      -       +      +
    297A  LEU*     4.5     5.1    -      -       +      +
    298A  LYS*     5.6     1.4    -      -       -      +
    309A  VAL*     3.4    24.7    -      -       -      +
    310A  GLU      2.8    25.8    +      -       -      +
    311A  ASP*     3.8     4.9    +      -       -      +
    312A  GLY      3.4    22.2    +      -       -      +
    313A  LEU      3.1     1.4    +      -       -      -
    314A  LYS*     1.3    75.6    -      -       -      +
    316A  ILE*     1.3    63.4    +      -       -      +
    317A  ILE      3.1     0.7    -      -       -      -
    318A  PRO*     3.3    22.2    -      -       +      +
    319A  ALA*     3.4    12.3    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 316 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128A  PRO*     3.8    30.1    -      -       +      -
    244A  PHE*     4.6     1.1    -      -       +      -
    282A  TYR*     3.8    28.7    -      -       +      -
    283A  LYS      4.6     4.7    -      -       -      +
    284A  GLU*     5.8     0.4    -      -       -      +
    285A  PRO*     3.8    28.7    -      -       +      -
    290A  TYR*     3.6    15.7    -      -       -      +
    313A  LEU*     3.1    25.8    +      -       +      +
    315A  ASN*     1.3    76.7    -      -       -      +
    317A  ILE*     1.3    63.5    +      -       +      +
    319A  ALA*     3.3     6.0    +      -       -      +
    320A  SER*     2.6    44.9    +      -       -      +
    361A  THR*     4.3     2.9    -      -       +      +
    374A  THR*     6.1     0.4    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 317 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  PRO*     3.5    33.9    -      -       +      +
     18A  TRP*     4.0    10.5    -      -       +      -
    107A  ALA*     3.5    23.2    -      -       +      +
    108A  GLY*     5.5     1.1    -      -       -      -
    128A  PRO*     3.7    23.1    -      -       +      -
    244A  PHE*     4.0    20.6    -      -       +      -
    314A  LYS      3.2    10.3    +      -       -      +
    315A  ASN      3.1     0.4    -      -       -      -
    316A  ILE*     1.3    79.5    -      -       +      +
    318A  PRO*     1.4    67.4    -      -       +      +
    320A  SER*     3.1     5.8    +      -       -      -
    321A  PHE*     2.9    52.9    +      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with PRO 318 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  PRO      3.5    12.8    -      -       -      +
     22A  ARG*     3.5    38.4    -      -       +      +
     23A  VAL*     4.2    13.2    -      -       +      -
     26A  ALA*     3.4    16.4    -      -       +      +
    293A  PHE*     4.2     0.7    -      -       +      -
    297A  LEU*     4.4    13.2    -      -       +      -
    314A  LYS      3.4     8.5    -      -       -      +
    315A  ASN*     3.3    24.0    -      -       -      +
    317A  ILE*     1.4    94.1    -      -       +      +
    319A  ALA*     1.3    53.5    +      -       -      -
    321A  PHE*     3.2     4.4    +      -       +      +
    322A  HIS*     2.9    23.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 319 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    290A  TYR*     3.8     9.2    -      -       +      -
    293A  PHE*     3.5    29.1    -      -       +      -
    315A  ASN      3.4    10.0    +      -       -      +
    316A  ILE      3.3     5.1    +      -       -      +
    317A  ILE      3.2     0.8    -      -       -      -
    318A  PRO*     1.3    78.2    -      -       -      +
    320A  SER*     1.3    58.0    +      -       -      +
    322A  HIS*     3.1     4.1    -      -       -      +
    323A  ASP*     2.8    32.1    +      -       -      +
    360A  VAL*     3.8     8.1    -      -       +      -
    361A  THR*     3.4    23.1    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 320 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    107A  ALA*     3.6    11.2    -      -       -      -
    126A  THR*     3.0    36.0    +      -       -      -
    127A  GLY*     4.0     5.3    -      -       -      -
    128A  PRO*     5.2     1.4    -      -       -      +
    316A  ILE*     2.6    31.8    +      -       -      +
    317A  ILE*     3.1     4.9    +      -       -      -
    319A  ALA*     1.3    70.5    -      -       -      +
    321A  PHE*     1.3    61.1    +      -       -      +
    323A  ASP*     4.1     6.5    -      -       -      +
    324A  GLY      2.7    23.9    +      -       -      -
    361A  THR*     4.0     4.0    -      -       -      +
    372A  ARG*     3.4    15.5    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with PHE 321 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  LEU*     4.2    21.5    -      -       +      -
     18A  TRP*     3.8    22.4    -      -       +      -
     23A  VAL*     3.7    30.7    -      -       +      +
     27A  VAL*     5.2     6.9    -      -       +      +
     82A  LEU*     3.8    27.7    -      -       +      +
     83A  GLY*     3.9    22.2    -      -       -      -
     85A  GLY*     5.1     0.4    -      -       -      -
    106A  THR*     3.7    13.5    -      -       -      -
    107A  ALA*     3.5    33.9    -      -       +      -
    108A  GLY      4.2     2.2    -      -       -      -
    126A  THR*     4.7     1.1    -      -       -      -
    317A  ILE*     2.9    28.9    +      -       +      -
    318A  PRO      3.2     7.8    +      -       -      +
    320A  SER*     1.3    75.1    -      -       -      +
    322A  HIS*     1.3    58.4    +      -       -      +
    324A  GLY*     3.7     0.8    -      -       -      -
    325A  LEU*     2.9    33.7    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with HIS 322 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26A  ALA*     3.3    27.5    -      -       +      +
     27A  VAL*     5.5     1.1    -      -       -      +
     29A  LEU*     4.2     7.4    +      -       +      +
     30A  ALA*     3.6    27.8    +      -       +      +
     33A  ARG*     3.9    12.6    +      -       -      +
    293A  PHE*     3.6    22.9    -      +       +      -
    318A  PRO      2.9    14.1    +      -       -      +
    319A  ALA      3.1     9.4    -      -       -      +
    321A  PHE*     1.3    76.8    -      -       -      +
    323A  ASP*     1.3    80.3    +      -       -      +
    325A  LEU*     3.5     3.9    +      -       -      +
    326A  LEU*     3.2    48.5    +      -       +      +
    360A  VAL*     3.6    26.8    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASP 323 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    319A  ALA      2.8    19.3    +      -       -      +
    320A  SER*     4.1     3.8    -      -       -      +
    321A  PHE      3.3     0.2    -      -       -      -
    322A  HIS*     1.3    93.8    +      -       -      +
    324A  GLY*     1.3    58.3    +      -       -      +
    326A  LEU*     3.1     9.5    +      -       -      +
    327A  LEU*     2.8    29.5    +      -       -      +
    357A  PHE*     4.0     4.4    -      -       +      -
    359A  GLY*     3.3    13.8    -      -       -      -
    360A  VAL*     3.0    17.6    +      -       -      +
    361A  THR*     2.6    39.4    +      -       -      +
    364A  LEU*     3.7    21.9    -      -       +      +
    372A  ARG*     5.1     0.2    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLY 324 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82A  LEU*     6.1     0.2    -      -       -      -
    105A  LEU*     4.1    11.8    -      -       -      +
    126A  THR*     3.7    27.7    +      -       -      -
    320A  SER      2.7    23.0    +      -       -      -
    321A  PHE*     3.7     0.9    -      -       -      -
    323A  ASP*     1.3    72.1    -      -       -      +
    325A  LEU*     1.3    55.4    +      -       -      +
    327A  LEU*     3.3     6.6    +      -       -      +
    328A  TYR*     2.9    30.1    +      -       -      +
    364A  LEU*     5.3     0.4    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 325 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      5A  VAL*     5.0    18.2    -      -       +      -
     27A  VAL*     3.9    37.7    -      -       +      -
     30A  ALA*     4.1    13.9    -      -       +      -
     31A  LEU*     4.1    20.0    -      -       +      -
     46A  VAL*     5.4     1.6    -      -       +      -
     48A  MET*     5.1     3.1    -      -       -      -
     80A  VAL*     6.1     0.4    -      -       +      -
     82A  LEU*     4.9    13.1    -      -       +      +
    105A  LEU*     4.6     8.0    -      -       +      +
    321A  PHE      2.9    19.9    +      -       -      +
    322A  HIS      3.6     5.6    -      -       -      +
    324A  GLY*     1.3    71.4    -      -       -      +
    326A  LEU*     1.3    58.5    +      -       +      +
    328A  TYR*     3.3    19.5    +      -       +      +
    329A  VAL*     2.9    42.0    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 326 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  ALA*     3.7    31.2    -      -       +      +
     33A  ARG*     3.6    32.5    -      -       +      +
     34A  VAL*     3.9    16.2    -      -       +      -
     40A  LEU*     6.0     2.6    -      -       +      +
    322A  HIS*     3.2    40.3    +      -       +      +
    323A  ASP*     3.1    11.7    +      -       -      +
    325A  LEU*     1.3    75.0    -      -       +      +
    327A  LEU*     1.3    61.4    +      -       -      +
    329A  VAL*     3.6     5.3    -      -       -      +
    330A  GLN*     2.9    30.8    +      -       -      +
    357A  PHE*     3.8    20.6    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 327 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  THR*     4.9     0.9    -      -       +      -
    126A  THR*     4.5    14.4    -      -       +      -
    323A  ASP      2.8    16.9    +      -       -      +
    324A  GLY*     3.6     7.0    -      -       -      +
    326A  LEU*     1.3    71.3    -      -       -      +
    328A  TYR*     1.3    62.7    +      -       -      +
    330A  GLN*     3.4     3.4    +      -       +      +
    331A  ALA*     3.0    22.7    +      -       -      +
    351A  ARG      5.1     0.4    -      -       -      +
    352A  MET*     4.0    30.7    -      -       +      +
    355A  ARG*     4.3    24.6    +      -       +      +
    356A  SER      5.5     0.2    -      -       -      -
    357A  PHE*     3.9    40.1    -      -       +      -
    364A  LEU*     4.6     5.6    -      -       +      -
    366A  ILE*     3.8    31.6    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with TYR 328 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3A  LEU*     3.7    24.5    -      -       +      +
      5A  VAL*     5.2     0.4    -      -       +      -
     46A  VAL*     6.2     0.4    -      -       +      -
     79A  ALA*     4.0    10.6    +      -       -      +
     80A  VAL*     3.5    41.1    -      -       +      +
    103A  PRO*     4.8     6.5    -      -       +      -
    105A  LEU*     3.4    34.3    -      -       +      -
    324A  GLY      2.9     9.4    +      -       -      +
    325A  LEU*     3.5    16.2    -      -       +      +
    327A  LEU*     1.3    77.5    -      -       -      +
    329A  VAL*     1.3    65.0    +      -       +      +
    331A  ALA*     3.2     3.3    +      -       -      +
    332A  VAL*     2.9    54.4    +      -       +      +
    342A  VAL      4.4     4.7    +      -       -      -
    348A  ILE*     3.7    21.0    -      -       +      +
    352A  MET*     3.7    18.8    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 329 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  LEU*     5.7     0.9    -      -       +      -
     34A  VAL*     3.8    29.2    -      -       +      -
     40A  LEU*     4.2    18.6    -      -       +      -
     41A  LEU*     3.8    35.9    -      -       +      +
     46A  VAL*     4.7     7.4    -      -       +      -
    325A  LEU*     2.9    39.0    +      -       +      +
    326A  LEU*     3.3     8.7    +      -       -      +
    328A  TYR*     1.3    80.3    -      -       +      +
    330A  GLN*     1.3    59.9    +      -       -      +
    332A  VAL*     4.7     0.4    -      -       -      -
    333A  THR*     2.9    28.2    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 330 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  ARG*     4.4    13.6    +      -       -      +
     40A  LEU*     3.9    26.6    -      -       -      +
    326A  LEU      2.9    18.4    +      -       -      +
    327A  LEU*     3.6     6.3    -      -       +      +
    329A  VAL*     1.3    73.1    -      -       -      +
    331A  ALA*     1.3    58.7    +      -       -      +
    333A  THR*     3.1    10.7    +      -       -      +
    334A  GLU*     2.9    49.7    +      -       -      +
    355A  ARG*     4.8     7.2    -      -       -      +
    357A  PHE*     4.0    24.8    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 331 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    327A  LEU      3.0    14.1    +      -       -      +
    328A  TYR      3.5     7.6    -      -       -      +
    330A  GLN*     1.3    76.7    -      -       -      +
    332A  VAL*     1.3    61.4    +      -       -      +
    334A  GLU*     3.3    14.7    +      -       -      +
    335A  THR*     3.0    27.2    +      -       -      -
    348A  ILE*     3.7    18.2    -      -       +      +
    351A  ARG*     3.7    11.5    -      -       +      +
    352A  MET*     3.7    23.8    -      -       +      -
    355A  ARG*     4.7     1.9    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 332 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3A  LEU*     4.0     3.1    -      -       +      -
     41A  LEU*     3.7    24.7    -      -       +      -
    328A  TYR*     2.9    60.9    +      -       +      +
    331A  ALA*     1.3    72.0    -      -       -      +
    333A  THR*     1.3    51.9    +      -       -      +
    335A  THR*     3.0     9.7    +      -       -      -
    336A  LEU*     2.8    37.3    +      -       +      +
    342A  VAL*     3.7    33.7    -      -       +      +
    348A  ILE*     3.8    14.1    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 333 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  ASP      3.7    22.2    -      -       -      +
     40A  LEU*     3.7    15.6    -      -       +      +
     41A  LEU*     2.9    25.8    +      -       -      +
     42A  PRO*     4.2     7.5    -      -       +      +
    329A  VAL      2.9    15.5    +      -       -      -
    330A  GLN*     3.1    13.8    +      -       -      +
    332A  VAL*     1.3    78.2    -      -       -      +
    334A  GLU*     1.3    58.3    +      -       +      +
    336A  LEU*     3.1    12.4    +      -       -      +
    337A  ALA*     2.9    30.2    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 334 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    330A  GLN*     2.9    33.0    +      -       +      +
    331A  ALA      3.6     5.6    -      -       -      +
    333A  THR*     1.3    77.2    -      -       +      +
    335A  THR*     1.3    59.2    +      -       -      +
    337A  ALA*     3.6     9.3    +      -       -      +
    338A  GLN*     3.4    29.7    +      -       -      +
    351A  ARG*     3.7    29.1    +      -       -      +
    355A  ARG*     2.5    49.4    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 335 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    331A  ALA      3.0    13.2    +      -       -      -
    332A  VAL*     3.0    10.8    +      -       -      -
    334A  GLU*     1.3    73.6    -      -       -      +
    336A  LEU*     1.3    63.7    +      -       -      +
    338A  GLN*     3.4     7.1    +      -       -      +
    339A  GLY      3.6     0.2    +      -       -      -
    340A  GLY*     2.9    40.1    +      -       -      -
    341A  THR      4.0    16.6    -      -       -      +
    344A  ASP*     4.5     4.9    -      -       +      -
    347A  ASN*     3.4    19.7    +      -       -      +
    348A  ILE*     3.8    20.1    -      -       +      +
    351A  ARG*     3.0    23.5    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 336 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41A  LEU*     4.3     6.7    -      -       +      -
     42A  PRO*     4.2    26.0    -      -       +      +
     44A  TRP*     3.6    42.0    -      -       +      +
    332A  VAL*     2.8    33.8    +      -       +      +
    333A  THR*     3.6     7.4    -      -       -      +
    335A  THR*     1.3    74.1    -      -       -      +
    337A  ALA*     1.3    61.8    +      -       -      +
    338A  GLN      3.2     1.0    +      -       -      -
    339A  GLY*     3.2    11.8    +      -       -      -
    340A  GLY      3.8    18.5    +      -       -      +
    341A  THR*     4.0    14.6    -      -       -      +
    342A  VAL*     4.1     6.7    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 337 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    333A  THR*     2.9    17.3    +      -       +      +
    334A  GLU*     3.7    10.5    -      -       -      +
    335A  THR      3.3     0.4    -      -       -      -
    336A  LEU*     1.3    78.4    -      -       -      +
    338A  GLN*     1.3    62.6    +      -       +      +
    339A  GLY      3.6     2.3    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 338 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    334A  GLU*     3.4    14.4    +      -       -      +
    335A  THR      3.4     4.1    +      -       -      +
    336A  LEU      3.2     0.8    -      -       -      -
    337A  ALA*     1.3    82.6    -      -       +      +
    339A  GLY*     1.3    56.8    +      -       -      +
    340A  GLY      3.4     3.4    +      -       -      -
    351A  ARG*     3.5    37.9    +      -       -      +
----------------------------------------------------------
 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