Contacts of the helix formed by residues 290 - 315 (chain A) in PDB entry 1U3Q


Residue contacts within the protein are derived with the CSU software (Sobolev V., Sorokine A., Prilusky J., Abola E.E. and Edelman M. (1999) Automated analysis of interatomic contacts in proteins. Bioinformatics, 15, 327-332). A short description of the analytical approach is given at the end of the page.
For CSU analysis of other PDB entry

Note:
Non-standard 3 letter residue codes indicate a heterogroup. To identify and analyse, use LPC software

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with THR 290 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    287A  ALA*     5.9     2.5    -      -       +      -
    288A  PRO      3.8    11.4    -      -       -      +
    289A  PHE*     1.3    75.3    -      -       -      +
    291A  GLU*     1.3    64.9    +      -       -      +
    292A  ALA*     3.2     8.9    +      -       -      +
    293A  SER*     2.7    34.7    +      -       -      +
    294A  MET*     2.9    24.2    +      -       -      +
    369A  CYS*     4.6     2.0    -      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 291 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    290A  THR*     1.3    72.4    -      -       -      +
    292A  ALA*     1.3    61.2    +      -       -      +
    294A  MET*     3.6     2.3    +      -       -      +
    295A  MET*     3.2    24.3    +      -       +      +
    369A  CYS*     3.3    25.0    +      -       -      +
    370A  VAL*     3.9    18.2    -      -       +      +
    371A  GLU*     3.2    32.3    +      -       -      +
    479A  MET*     4.9     4.5    -      -       -      +
    482A  LYS*     5.7     1.0    +      -       -      +
    484A  VAL*     3.3    31.7    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 292 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    290A  THR*     3.1     7.0    +      -       -      +
    291A  GLU*     1.3    76.9    -      -       -      +
    293A  SER*     1.3    59.8    +      -       -      +
    295A  MET*     3.3     2.6    +      -       -      +
    296A  MET*     2.9    29.0    +      -       -      +
    484A  VAL*     3.9    27.7    -      -       +      +
    486A  PRO*     5.5     0.5    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 293 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    285A  PRO*     4.3    16.2    -      -       -      +
    288A  PRO      4.4     0.3    +      -       -      -
    289A  PHE*     3.4    11.8    -      -       -      -
    290A  THR*     2.7    47.9    +      -       -      +
    292A  ALA*     1.3    71.2    -      -       -      +
    294A  MET*     1.3    59.1    +      -       -      +
    296A  MET*     3.2    12.6    +      -       -      +
    297A  SER*     2.8    33.6    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with MET 294 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    289A  PHE*     3.7    32.5    -      -       +      -
    290A  THR      2.9    17.5    +      -       -      +
    291A  GLU      3.9     3.6    -      -       -      +
    293A  SER*     1.3    77.4    +      -       -      +
    295A  MET*     1.3    57.8    +      -       -      +
    297A  SER*     3.3     2.8    +      -       -      -
    298A  LEU*     3.1    37.3    +      -       +      +
    362A  LEU*     4.0    23.1    -      -       +      -
    366A  GLU      2.9    29.6    -      -       -      +
    367A  GLY*     4.2     6.3    -      -       -      -
    369A  CYS*     3.6    13.2    -      -       +      -
    370A  VAL*     3.2    34.5    -      -       +      +
    373A  ILE*     4.2     5.2    -      -       +      -
    377A  PHE*     4.4     5.8    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with MET 295 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    291A  GLU      3.2    15.8    +      -       -      +
    292A  ALA      3.7     4.7    -      -       -      +
    293A  SER      3.2     0.2    -      -       -      -
    294A  MET*     1.3    75.1    -      -       -      +
    296A  MET*     1.3    66.2    +      -       -      +
    297A  SER      3.1     1.3    -      -       -      -
    298A  LEU*     3.8    11.9    -      -       +      +
    299A  THR*     2.9    34.0    +      -       -      +
    370A  VAL*     3.2    40.6    -      -       +      -
    373A  ILE*     3.3    28.3    -      -       +      -
    475A  HIS*     4.1     1.8    -      -       +      -
    479A  MET*     4.0     7.6    -      -       -      -
    484A  VAL*     4.4     8.3    -      -       +      +
    485A  VAL*     3.1    39.7    -      -       +      -
    501A  272      3.8    20.4    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with MET 296 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    282A  ILE*     5.9     0.4    -      -       +      -
    285A  PRO*     5.6     5.8    -      -       +      -
    292A  ALA      2.9    17.9    +      -       -      +
    293A  SER*     3.5    11.9    -      -       -      +
    295A  MET*     1.3    77.3    -      -       -      +
    297A  SER*     1.3    66.6    +      -       -      +
    299A  THR*     3.5     6.5    +      -       -      +
    300A  LYS*     2.7    72.8    +      -       +      +
    486A  PRO*     5.1    19.0    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 297 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    282A  ILE*     3.1    28.1    -      -       -      +
    283A  SER      4.9     2.4    +      -       -      -
    285A  PRO*     4.2     7.6    -      -       -      +
    289A  PHE*     3.5    23.3    -      -       -      -
    293A  SER      2.8    21.9    +      -       -      -
    294A  MET      3.4     7.9    -      -       -      -
    296A  MET*     1.3    89.3    -      -       -      +
    298A  LEU*     1.3    58.9    +      -       -      +
    301A  LEU*     3.1    23.4    +      -       -      +
    360A  LEU*     4.7     9.9    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 298 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    294A  MET*     3.1    24.9    +      -       +      +
    295A  MET*     3.8    12.8    -      -       +      +
    297A  SER*     1.3    75.5    -      -       -      +
    299A  THR*     1.3    59.8    +      -       -      +
    300A  LYS      3.1     1.3    -      -       -      -
    301A  LEU*     3.3     5.2    +      -       +      +
    302A  ALA*     2.9    30.2    +      -       -      +
    356A  PHE*     3.8    40.8    -      -       +      -
    360A  LEU*     4.8     6.7    -      -       +      -
    362A  LEU*     4.6     9.0    -      -       +      -
    373A  ILE*     3.5    33.4    -      -       +      -
    377A  PHE*     4.7     5.8    -      -       +      -
    501A  272      3.7    28.7    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 299 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    295A  MET*     2.9    23.9    +      -       -      +
    296A  MET*     3.5     9.0    +      -       -      +
    298A  LEU*     1.3    74.5    -      -       -      +
    300A  LYS*     1.3    60.2    +      -       -      +
    302A  ALA*     4.0     1.1    -      -       -      -
    303A  ASP*     3.1    30.1    +      -       -      +
    476A  LEU*     3.9    17.0    -      -       +      -
    485A  VAL*     4.2     9.9    -      -       +      +
    486A  PRO*     5.2     3.8    -      -       -      +
    487A  VAL*     3.6    31.2    +      -       +      +
    491A  LEU*     3.7    20.4    -      -       +      +
    501A  272      4.8     6.1    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 300 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    282A  ILE*     4.4    17.7    -      -       +      +
    296A  MET*     2.7    51.0    +      -       +      +
    297A  SER      3.7     4.7    -      -       -      +
    299A  THR*     1.3    77.8    +      -       -      +
    301A  LEU*     1.3    63.9    +      -       -      +
    303A  ASP*     3.9     3.9    -      -       -      +
    304A  LYS*     3.1    49.5    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 301 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    280A  VAL*     3.6    41.7    -      -       +      +
    282A  ILE*     4.4    14.8    -      -       +      +
    297A  SER      3.1    19.0    +      -       -      +
    298A  LEU*     3.6     4.5    -      -       -      +
    300A  LYS*     1.3    74.7    -      -       -      +
    302A  ALA*     1.3    66.5    +      -       -      +
    304A  LYS*     3.2     5.5    +      -       -      +
    305A  GLU*     3.0    39.5    +      -       -      +
    356A  PHE*     3.4    48.0    -      -       +      +
    360A  LEU*     4.3     7.2    -      -       +      -
    501A  272      4.0    16.2    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 302 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    298A  LEU      2.9    16.7    +      -       -      +
    299A  THR*     4.1     3.8    -      -       -      +
    301A  LEU*     1.3    75.8    -      -       -      +
    303A  ASP*     1.3    64.4    +      -       -      +
    305A  GLU*     2.8    24.8    +      -       -      +
    306A  LEU*     2.9    17.1    +      -       -      +
    335A  TRP*     4.6     2.2    -      -       +      -
    336A  MET*     6.2     0.4    -      -       +      -
    339A  LEU*     3.7    21.5    -      -       +      -
    476A  LEU*     6.4     0.4    -      -       +      -
    491A  LEU*     4.4    19.3    -      -       +      -
    501A  272      4.0     9.8    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ASP 303 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    299A  THR      3.1    19.8    +      -       -      +
    300A  LYS*     3.9     5.6    -      -       -      +
    302A  ALA*     1.3    79.7    -      -       -      +
    304A  LYS*     1.3    67.4    +      -       -      +
    306A  LEU*     3.5    14.2    +      -       -      -
    307A  VAL*     3.9     4.0    +      -       -      +
    489A  ASP*     5.2     3.4    -      -       -      +
    490A  LEU*     3.2    47.1    +      -       -      +
    491A  LEU*     3.6    14.9    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 304 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    280A  VAL*     3.8    29.3    -      -       +      +
    281A  LEU      4.1    17.4    +      -       -      -
    282A  ILE*     6.0     3.2    -      -       +      +
    300A  LYS*     3.1    39.7    -      -       +      +
    301A  LEU*     3.2     4.4    +      -       -      +
    302A  ALA      3.1     0.8    -      -       -      -
    303A  ASP*     1.3    81.8    -      -       -      +
    305A  GLU*     1.3    64.2    +      -       -      +
    306A  LEU      3.5     0.2    +      -       -      -
    307A  VAL*     3.6    19.1    +      -       -      +
    308A  HIS*     3.8     8.0    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 305 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    280A  VAL*     3.6    24.7    +      -       +      +
    301A  LEU*     3.0    28.8    +      -       +      +
    302A  ALA*     2.8     8.5    +      -       -      +
    304A  LYS*     1.3    74.5    -      -       -      +
    306A  LEU*     1.3    60.5    +      -       -      +
    307A  VAL      3.2     0.7    -      -       -      -
    308A  HIS*     3.0     8.4    +      -       +      +
    309A  MET*     2.8    28.6    +      -       -      +
    339A  LEU*     3.7    20.9    -      -       +      +
    346A  ARG*     3.9    19.4    +      -       -      -
    356A  PHE      4.9     0.2    -      -       -      +
    501A  272      2.4    43.0    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 306 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    302A  ALA      2.9    19.1    +      -       -      +
    303A  ASP*     3.7     2.7    -      -       -      +
    304A  LYS      3.3     0.2    -      -       -      -
    305A  GLU*     1.3    77.8    -      -       -      +
    307A  VAL*     1.3    59.8    +      -       -      +
    309A  MET*     3.7    22.6    -      -       +      +
    310A  ILE*     3.0    34.5    +      -       +      +
    335A  TRP*     3.7    22.9    -      -       +      -
    339A  LEU*     4.2     5.2    -      -       +      -
    490A  LEU*     3.5    21.1    -      -       +      -
    491A  LEU*     3.8    29.4    -      -       +      -
    494A  MET*     3.4    45.0    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 307 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    303A  ASP*     3.9     7.4    -      -       -      +
    304A  LYS*     3.8    11.0    -      -       -      +
    305A  GLU      3.2     0.4    -      -       -      -
    306A  LEU*     1.3    78.9    -      -       -      +
    308A  HIS*     1.3    68.0    +      -       +      +
    310A  ILE*     3.6    16.0    +      -       +      +
    311A  SER*     3.3    17.9    +      -       -      +
    490A  LEU*     3.8    19.7    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with HIS 308 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    277A  PRO*     3.8    24.5    -      -       +      +
    278A  PRO*     3.8    37.1    +      -       +      +
    279A  HIS      5.1     1.8    +      -       -      -
    280A  VAL*     3.4    33.8    -      -       +      +
    304A  LYS      3.8     7.2    +      -       -      -
    305A  GLU*     3.0     8.8    +      -       +      +
    307A  VAL*     1.3    82.2    -      -       +      +
    309A  MET*     1.3    59.5    +      -       -      +
    311A  SER*     3.3     9.1    +      -       -      -
    312A  TRP*     3.0    28.7    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with MET 309 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    277A  PRO*     5.0     1.5    -      -       -      +
    305A  GLU      2.8    13.6    +      -       -      +
    306A  LEU*     3.3    17.9    +      -       +      +
    308A  HIS*     1.3    76.3    -      -       -      +
    310A  ILE*     1.3    58.5    +      -       +      +
    312A  TRP*     3.3    25.1    -      -       +      +
    313A  ALA*     2.9    26.2    +      -       -      +
    331A  LEU*     4.3    15.9    -      -       +      -
    334A  CYS*     5.4     0.2    -      -       -      -
    335A  TRP*     3.1    46.0    -      -       -      +
    338A  VAL*     3.7    22.7    -      -       +      -
    339A  LEU*     3.5    27.1    -      -       +      -
    494A  MET*     4.9     2.7    -      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 310 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    306A  LEU*     3.0    23.3    +      -       +      +
    307A  VAL*     3.8    11.4    -      -       +      +
    308A  HIS      3.2     0.2    -      -       -      -
    309A  MET*     1.3    75.7    -      -       +      +
    311A  SER*     1.3    62.4    +      -       -      +
    313A  ALA*     3.4     6.0    +      -       -      +
    314A  LYS*     3.0    48.4    +      -       +      +
    331A  LEU*     4.7    16.6    -      -       +      -
    490A  LEU*     4.7    12.3    -      -       +      -
    494A  MET*     5.6     3.8    -      -       +      -
    323B  SER*     6.2     2.9    -      -       -      -
    324B  LEU*     5.1    12.1    -      -       +      +
    325B  PHE*     3.6    35.2    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 311 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    277A  PRO*     5.9     2.5    -      -       -      -
    307A  VAL*     3.3    14.8    +      -       -      +
    308A  HIS*     3.3    11.0    +      -       -      -
    310A  ILE*     1.3    77.6    -      -       -      +
    312A  TRP*     1.3    63.5    +      -       -      +
    314A  LYS*     3.3    10.2    +      -       -      +
    315A  LYS*     3.1    47.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with TRP 312 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    272A  LEU*     5.1     4.4    +      -       -      +
    275A  ALA*     3.5    40.6    -      -       +      +
    276A  GLU*     4.3     5.3    +      -       -      -
    277A  PRO*     4.1    15.9    -      -       +      +
    308A  HIS      3.0    14.8    +      -       -      +
    309A  MET*     3.3    34.5    -      -       +      +
    310A  ILE      3.2     0.2    -      -       -      -
    311A  SER*     1.3    76.9    -      -       -      +
    313A  ALA*     1.3    68.4    +      -       +      +
    315A  LYS*     3.0    15.5    +      -       -      +
    316A  ILE*     3.4    29.6    +      -       +      +
    338A  VAL*     4.0    16.6    -      -       +      -
    398A  LEU      5.9     0.4    +      -       -      -
    401A  LYS*     3.4    62.3    -      -       +      +
    402A  ALA*     4.0     3.3    -      -       +      +
    405A  LEU*     3.7    34.5    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 313 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    309A  MET      2.9    16.5    +      -       -      +
    310A  ILE      3.4     3.6    +      -       -      +
    312A  TRP*     1.3    81.2    -      -       +      +
    314A  LYS*     1.3    61.8    +      -       -      +
    316A  ILE*     3.1    20.2    +      -       -      +
    319A  PHE*     3.2    37.9    -      -       +      +
    331A  LEU*     3.9    14.1    -      -       +      -
    405A  LEU*     3.8    21.8    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 314 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    310A  ILE*     3.0    34.9    +      -       +      +
    311A  SER*     3.7     9.0    -      -       -      +
    312A  TRP      3.2     0.4    -      -       -      -
    313A  ALA*     1.3    76.0    -      -       -      +
    315A  LYS*     1.3    60.8    +      -       +      +
    316A  ILE      3.3     4.3    +      -       -      +
    319A  PHE*     4.2    11.0    -      -       +      -
    320A  VAL*     3.3    39.0    -      -       +      +
    327A  GLN*     4.9     2.5    -      -       -      +
    324B  LEU*     4.5    25.4    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 315 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    271A  THR*     3.2    25.1    -      -       -      +
    274A  GLU*     4.3    26.6    -      -       -      +
    275A  ALA*     3.7    34.3    -      -       +      +
    311A  SER*     3.1    36.3    +      -       -      +
    312A  TRP      3.0     9.8    +      -       -      +
    314A  LYS*     1.3    78.9    -      -       -      +
    316A  ILE*     1.3    61.1    +      -       -      +
----------------------------------------------------------
 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