Contacts of the helix formed by residues 276 - 298 (chain Q) in PDB entry 1HI0


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 PRO 276 (chain Q).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    151Q  THR      4.0     1.3    -      -       -      +
    153Q  ILE*     3.3    27.4    -      -       +      +
    190Q  TYR*     5.7     0.2    -      -       +      -
    194Q  GLN      4.3     9.9    -      -       -      +
    196Q  GLY      3.3    27.1    -      -       -      +
    198Q  ALA      3.4    20.4    -      -       -      +
    199Q  TYR*     4.6     3.8    -      -       +      -
    275Q  GLY*     1.3    80.4    -      -       -      +
    277Q  PHE*     1.3    65.9    +      -       -      +
    278Q  ALA      3.4     1.3    -      -       -      -
    279Q  LEU*     3.1    23.2    +      -       +      -
    280Q  ASN*     3.1    13.1    +      -       -      +
    363Q  LEU*     4.0    15.0    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with PHE 277 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6E    C      5.1    10.5    -      -       -      -
    143Q  LEU*     5.5     1.8    -      -       +      -
    145Q  ILE*     4.0    31.0    -      -       +      -
    150Q  SER      5.6     0.9    -      -       -      -
    151Q  THR*     3.2    44.6    +      -       +      +
    153Q  ILE      4.0     2.0    +      -       -      -
    163Q  LYS*     3.8    26.9    -      -       +      -
    166Q  ILE*     3.3    24.5    -      -       +      -
    167Q  ALA*     4.0    14.1    -      -       +      -
    275Q  GLY      3.2     3.4    +      -       -      +
    276Q  PRO*     1.3    69.1    -      -       -      +
    278Q  ALA*     1.3    66.6    +      -       -      +
    279Q  LEU      2.9     0.2    +      -       -      -
    280Q  ASN*     3.1     6.0    +      -       +      +
    281Q  ALA*     2.9    30.7    +      -       +      +
    284Q  MET*     4.0    29.8    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 278 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    153Q  ILE      5.4     0.6    +      -       -      -
    154Q  PRO*     6.1     0.2    -      -       +      -
    166Q  ILE*     4.4    14.2    -      -       +      +
    170Q  ALA*     3.3    19.7    -      -       +      +
    193Q  HIS      3.2    27.1    -      -       -      +
    194Q  GLN*     3.2    23.8    +      -       +      +
    195Q  MET*     3.4    11.7    -      -       +      +
    276Q  PRO      3.4     0.6    +      -       -      -
    277Q  PHE*     1.3    76.9    -      -       -      +
    279Q  LEU*     1.3    57.2    +      -       -      +
    282Q  PRO*     3.0    20.4    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 279 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181Q  MET*     4.5     4.0    -      -       +      -
    194Q  GLN      4.4     0.2    +      -       -      -
    195Q  MET*     4.0    17.5    -      -       +      +
    196Q  GLY*     4.1    16.2    -      -       -      +
    199Q  TYR*     5.7     0.7    -      -       -      +
    276Q  PRO*     3.1    26.1    +      -       +      +
    277Q  PHE      3.0     0.2    -      -       -      -
    278Q  ALA*     1.3    77.1    -      -       -      +
    280Q  ASN*     1.3    67.2    +      -       -      +
    281Q  ALA      3.2     1.8    -      -       -      -
    282Q  PRO*     3.0    18.3    -      -       +      +
    283Q  ILE*     3.6     9.5    -      -       +      +
    356Q  LEU*     4.0    43.7    -      -       +      +
    359Q  THR*     5.0     2.9    -      -       +      -
    360Q  SER*     4.0    29.8    -      -       -      +
    363Q  LEU*     4.4    13.7    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ASN 280 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6E    C      6.2     0.9    -      -       -      -
    199Q  TYR*     4.2     5.5    +      -       -      -
    275Q  GLY*     3.2    36.9    -      -       -      +
    276Q  PRO*     3.1     5.0    +      -       -      +
    277Q  PHE*     3.1    10.1    +      -       +      +
    279Q  LEU*     1.3    79.3    -      -       -      +
    281Q  ALA*     1.3    51.9    +      -       -      +
    283Q  ILE*     3.1    11.8    +      -       -      +
    284Q  MET*     2.6    55.1    +      -       -      +
    360Q  SER*     4.9     2.0    -      -       -      -
    394Q  GLY      3.4    12.6    -      -       -      +
    395Q  GLN*     3.4    14.5    -      -       -      +
    396Q  GLY      3.1    23.7    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 281 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    143Q  LEU*     4.1    15.3    -      -       +      +
    167Q  ALA*     4.2    18.4    -      -       +      +
    170Q  ALA*     3.9    15.7    -      -       +      -
    171Q  LEU*     4.3     3.6    -      -       +      -
    277Q  PHE*     2.9    21.4    +      -       +      +
    280Q  ASN*     1.3    76.0    -      -       -      +
    282Q  PRO*     1.3    72.4    -      -       +      +
    284Q  MET*     3.0    12.6    +      -       -      +
    285Q  ALA*     2.9    23.2    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with PRO 282 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    170Q  ALA*     4.1     5.8    -      -       +      -
    171Q  LEU*     3.7     7.8    -      -       +      -
    174Q  ALA*     3.8    21.3    -      -       +      -
    195Q  MET*     4.6     2.5    -      -       +      -
    278Q  ALA      3.0    21.5    -      -       -      +
    279Q  LEU*     3.0    17.5    -      -       +      +
    281Q  ALA*     1.3    93.2    -      -       +      +
    283Q  ILE*     1.3    58.5    +      -       +      +
    285Q  ALA*     3.6     4.3    -      -       -      +
    286Q  VAL*     3.6     2.8    -      -       -      +
    353Q  TRP*     3.1    19.6    +      -       -      +
    356Q  LEU*     4.4    15.5    -      -       +      -
    657Q  PHE*     3.5    33.4    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 283 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    279Q  LEU*     3.6    22.2    -      -       +      +
    280Q  ASN*     3.1    15.7    +      -       -      +
    281Q  ALA      3.0     0.4    -      -       -      -
    282Q  PRO*     1.3    77.1    -      -       +      +
    284Q  MET*     1.3    66.9    +      -       -      +
    285Q  ALA      3.1     1.6    -      -       -      -
    286Q  VAL*     3.0     5.5    +      -       -      +
    287Q  ALA*     2.9    19.6    +      -       +      +
    353Q  TRP*     4.2    10.7    -      -       +      +
    356Q  LEU*     4.4     3.6    -      -       +      +
    357Q  PHE*     4.1    37.2    -      -       +      +
    360Q  SER*     3.4    35.4    -      -       -      +
    395Q  GLN*     4.1     5.6    -      -       -      +
    396Q  GLY*     3.8    24.9    -      -       -      -
    397Q  ALA*     4.2     3.1    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with MET 284 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6E    C      4.7    28.7    -      -       -      +
    143Q  LEU*     3.6    30.7    -      -       +      +
    144Q  LYS      3.8    10.8    -      -       -      +
    145Q  ILE*     5.2     3.4    -      -       +      -
    277Q  PHE*     4.0    23.8    -      -       +      -
    280Q  ASN*     2.6    36.0    +      -       -      +
    281Q  ALA*     3.0     4.9    +      -       -      +
    283Q  ILE*     1.3    72.3    -      -       -      +
    285Q  ALA*     1.3    62.7    +      -       -      +
    286Q  VAL      3.0     1.4    +      -       -      -
    287Q  ALA*     3.9     7.9    -      -       -      -
    288Q  GLN*     3.1    27.0    +      -       -      +
    291Q  ARG*     5.1     0.4    +      -       -      +
    396Q  GLY*     3.9    20.2    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 285 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    141Q  VAL*     5.3     3.8    +      -       -      +
    143Q  LEU*     4.4    15.4    -      -       +      +
    171Q  LEU*     4.1    11.0    -      -       +      -
    281Q  ALA      2.9    14.2    +      -       -      +
    282Q  PRO      3.6     0.4    -      -       -      +
    284Q  MET*     1.3    76.9    -      -       -      +
    286Q  VAL*     1.3    58.2    +      -       -      +
    288Q  GLN*     5.6     0.4    -      -       -      -
    289Q  PRO*     3.2    20.1    -      -       -      +
    654Q  THR*     5.2     8.2    -      -       -      -
    657Q  PHE*     3.5    34.3    -      -       +      -
    658Q  LEU*     3.4     9.9    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 286 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135Q  PHE*     4.5    10.3    -      -       +      -
    138Q  LEU*     4.4    11.7    -      -       +      -
    282Q  PRO      3.6     4.0    -      -       -      +
    283Q  ILE      3.0     1.9    +      -       -      +
    285Q  ALA*     1.3    77.4    -      -       -      +
    287Q  ALA*     1.3    67.7    +      -       -      +
    288Q  GLN      3.3     2.0    -      -       -      -
    289Q  PRO*     3.0    13.6    -      -       -      +
    290Q  VAL*     3.1    25.3    +      -       +      +
    349Q  TYR*     4.5     7.4    -      -       +      -
    353Q  TRP*     3.3    52.9    -      -       +      +
    657Q  PHE*     4.4     3.1    -      -       +      -
    658Q  LEU*     3.9    17.7    -      -       +      -
    661Q  VAL*     4.2     9.9    -      -       +      -
    662Q  MET*     5.8     0.2    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 287 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135Q  PHE*     6.2     0.7    -      -       -      -
    283Q  ILE*     2.9    16.7    +      -       +      +
    284Q  MET*     3.7     5.8    -      -       -      +
    286Q  VAL*     1.3    77.6    -      -       -      +
    288Q  GLN*     1.3    57.8    +      -       -      +
    290Q  VAL*     3.0     8.0    +      -       -      +
    291Q  ARG*     2.8    42.9    +      -       -      +
    396Q  GLY      3.6    23.1    -      -       -      +
    397Q  ALA*     4.1    13.5    -      -       +      -
    400Q  LEU*     3.6     8.9    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 288 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    141Q  VAL*     3.8    19.3    -      -       +      -
    142Q  PRO      5.1     5.8    -      -       -      +
    143Q  LEU*     6.4     1.1    -      -       -      -
    144Q  LYS*     6.4     1.8    -      -       +      +
    284Q  MET      3.1    10.4    +      -       -      +
    285Q  ALA      5.3     0.2    -      -       -      -
    287Q  ALA*     1.3    78.7    -      -       -      +
    289Q  PRO*     1.3    71.9    -      -       +      +
    291Q  ARG*     2.9    45.7    +      -       -      +
    292Q  ASN*     2.9    40.1    +      -       -      +
    633Q  THR*     5.0     7.5    +      -       -      -
    634Q  GLU*     5.3    14.2    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with PRO 289 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    138Q  LEU*     3.6    30.2    -      -       +      +
    139Q  GLU      3.7    18.4    +      -       -      +
    141Q  VAL*     3.7    17.7    -      -       +      +
    285Q  ALA      3.2    23.8    -      -       -      +
    286Q  VAL*     3.0    18.6    -      -       -      +
    288Q  GLN*     1.3    90.7    -      -       +      +
    290Q  VAL*     1.3    61.4    +      -       -      +
    292Q  ASN*     3.3    11.5    +      -       +      +
    293Q  LYS*     3.1    18.4    +      -       -      +
    658Q  LEU*     4.3    10.1    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 290 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    134Q  MET*     3.7    30.7    -      -       +      +
    135Q  PHE*     3.8    30.3    -      -       +      -
    138Q  LEU*     3.8    24.7    -      -       +      -
    286Q  VAL      3.1    18.2    +      -       -      +
    287Q  ALA*     3.0     9.9    +      -       -      +
    289Q  PRO*     1.3    76.2    -      -       -      +
    291Q  ARG*     1.3    64.3    +      -       -      +
    293Q  LYS*     3.1     4.2    +      -       -      +
    294Q  ILE*     3.1    23.8    +      -       +      +
    400Q  LEU*     3.7    26.2    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 291 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6E    C      4.4    10.1    +      -       -      -
    284Q  MET      5.1     0.2    +      -       -      -
    287Q  ALA*     2.8    18.0    +      -       -      +
    288Q  GLN*     2.9    57.2    +      -       -      +
    290Q  VAL*     1.3    76.5    -      -       -      +
    292Q  ASN*     1.3    63.4    +      -       -      +
    294Q  ILE*     3.5     6.9    +      -       -      +
    295Q  TYR*     2.9    55.0    +      -       +      +
    396Q  GLY      3.3    23.2    +      -       -      -
    397Q  ALA*     4.3     0.6    -      -       -      +
    399Q  ASP*     2.7    38.6    +      -       -      -
    400Q  LEU*     4.2    13.2    -      -       +      -
    633Q  THR*     5.3     2.0    -      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ASN 292 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    139Q  GLU      4.9     1.4    +      -       -      +
    141Q  VAL*     3.7    27.7    -      -       -      +
    288Q  GLN*     2.9    42.2    +      -       -      +
    289Q  PRO*     3.6    12.8    -      -       +      +
    291Q  ARG*     1.3    76.1    -      -       -      +
    293Q  LYS*     1.3    54.2    +      -       -      +
    295Q  TYR*     3.8     6.2    -      -       -      +
    296Q  SER*     2.6    36.5    +      -       -      -
    633Q  THR*     5.7     0.3    +      -       -      -
    635Q  ALA*     6.1     0.7    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 293 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    133Q  LEU      3.1    19.7    +      -       -      +
    134Q  MET      4.1     4.0    -      -       -      +
    136Q  SER*     2.4    30.5    +      -       -      +
    137Q  ASP*     2.7    42.4    +      -       -      +
    138Q  LEU*     4.0    14.1    -      -       +      -
    289Q  PRO      3.1    12.8    +      -       -      +
    290Q  VAL      3.1     8.0    +      -       -      +
    292Q  ASN*     1.3    76.9    -      -       -      +
    294Q  ILE*     1.3    66.5    +      -       +      +
    296Q  SER*     2.7    19.8    +      -       -      -
    297Q  LYS*     2.9    40.3    +      -       +      +
    298Q  TYR*     4.7     4.5    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 294 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    134Q  MET*     3.9    52.5    -      -       +      -
    290Q  VAL*     3.1    12.4    +      -       +      +
    291Q  ARG      3.5    10.1    -      -       -      +
    293Q  LYS*     1.3    77.7    -      -       +      +
    295Q  TYR*     1.3    77.1    +      -       +      +
    298Q  TYR*     3.0    49.0    +      -       +      +
    302Q  PHE*     3.7    30.2    -      -       +      +
    400Q  LEU*     4.0    18.6    -      -       +      -
    403Q  THR*     5.0     4.3    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with TYR 295 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    288Q  GLN*     5.8     0.2    -      -       -      -
    291Q  ARG*     2.9    47.7    +      -       +      +
    292Q  ASN*     4.0     6.1    -      -       -      +
    294Q  ILE*     1.3    87.8    -      -       +      +
    296Q  SER*     1.3    56.6    +      -       -      +
    299Q  ALA*     3.1    21.5    -      -       -      +
    302Q  PHE*     3.5    37.2    -      -       +      -
    303Q  HIS*     3.2    29.8    +      +       +      +
    399Q  ASP*     4.1    12.5    +      -       -      -
    400Q  LEU*     5.7     0.9    -      -       +      +
    451Q  LYS*     3.1    32.9    +      -       +      +
    633Q  THR*     3.8    30.7    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 296 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    292Q  ASN      2.6    22.5    +      -       -      -
    293Q  LYS*     2.7    16.3    +      -       -      -
    295Q  TYR*     1.3    75.8    -      -       -      +
    297Q  LYS*     1.3    66.5    +      -       -      +
    298Q  TYR      3.1     0.7    -      -       -      -
    299Q  ALA*     2.9    21.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 297 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    133Q  LEU*     5.5     2.2    -      -       -      +
    137Q  ASP*     5.8     1.8    +      -       -      -
    293Q  LYS*     2.9    29.3    +      -       +      +
    296Q  SER*     1.3    82.0    +      -       -      +
    298Q  TYR*     1.3   102.4    +      -       +      +
    299Q  ALA      3.4     0.9    +      -       -      -
    437Q  ASP*     3.4    14.6    +      -       -      -
    441Q  GLN*     3.9    21.7    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with TYR 298 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    133Q  LEU*     3.4    41.3    +      -       +      +
    293Q  LYS*     4.6     4.6    -      -       +      -
    294Q  ILE*     3.0    33.7    +      -       +      +
    297Q  LYS*     1.3   111.4    +      -       +      +
    299Q  ALA*     1.3    66.0    +      -       -      +
    300Q  TYR      3.0     4.6    +      -       -      +
    301Q  THR      3.1     4.2    +      -       -      -
    302Q  PHE*     3.1    31.1    +      -       +      +
    437Q  ASP*     2.8    44.5    +      -       -      -
    440Q  TRP*     3.5    42.0    -      +       +      -
    441Q  GLN*     4.0     9.0    -      -       +      +
----------------------------------------------------------
 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