Contacts of the helix formed by residues 543 - 569 (chain A) in PDB entry 1E3H


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 543 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    503A  TYR*     3.4    33.4    -      -       +      +
    542A  ILE*     1.3    88.8    -      -       +      +
    544A  ALA*     1.3    66.8    +      -       -      +
    545A  SER*     4.0    10.8    -      -       -      +
    546A  VAL*     2.9    29.2    +      -       +      +
    547A  LEU*     3.1    10.4    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 544 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    542A  ILE      3.5     2.9    +      -       -      -
    543A  PRO*     1.3    71.4    -      -       -      +
    545A  SER*     1.3    57.4    -      -       -      +
    547A  LEU*     3.3     8.8    +      -       -      +
    548A  ALA*     3.0    30.4    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 545 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    543A  PRO*     4.0    11.3    -      -       -      +
    544A  ALA*     1.3    79.8    -      -       -      +
    546A  VAL*     1.3    62.5    +      -       -      +
    548A  ALA*     3.8     7.2    -      -       -      +
    549A  ALA*     3.0    28.2    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 546 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    492A  LEU*     4.4    13.2    -      -       +      -
    503A  TYR*     3.7    45.3    -      -       +      -
    542A  ILE*     3.8    17.0    -      -       +      -
    543A  PRO*     2.9    29.4    +      -       +      +
    545A  SER*     1.3    79.0    +      -       -      +
    547A  LEU*     1.3    59.9    +      -       -      +
    549A  ALA*     3.2     5.8    +      -       -      +
    550A  ALA*     2.9    28.4    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 547 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    226A  ALA*     4.3    19.3    -      -       +      +
    229A  LEU*     4.1    24.9    -      -       +      -
    519A  MSE      5.1     5.8    -      -       +      -
    521A  PHE*     6.3     2.7    -      -       +      -
    535A  LEU*     4.9    18.2    -      -       +      -
    542A  ILE*     3.6    26.8    -      -       +      +
    543A  PRO      3.1     5.9    +      -       -      +
    544A  ALA*     3.7    10.1    -      -       -      +
    546A  VAL*     1.3    77.7    -      -       -      +
    548A  ALA*     1.3    64.0    +      -       -      +
    550A  ALA*     3.2     7.7    +      -       +      +
    551A  LEU*     2.9    42.7    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 548 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  GLU*     5.7     1.3    -      -       -      +
    223A  GLU*     6.0     2.0    -      -       -      +
    226A  ALA*     6.2     2.0    -      -       -      -
    544A  ALA      3.0    16.0    +      -       -      +
    545A  SER*     3.8     8.3    -      -       -      +
    547A  LEU*     1.3    78.4    -      -       -      +
    549A  ALA*     1.3    57.1    +      -       -      +
    551A  LEU*     3.4     8.8    +      -       -      +
    552A  LYS*     2.9    30.8    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 549 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    545A  SER      3.0    19.9    +      -       -      +
    546A  VAL*     3.5     7.6    -      -       -      +
    548A  ALA*     1.3    74.1    -      -       -      +
    550A  ALA*     1.3    58.9    +      -       -      +
    552A  LYS*     3.3     8.1    +      -       -      +
    553A  GLN*     2.9    31.8    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 550 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    490A  MSE      4.9     0.9    -      -       -      +
    492A  LEU*     4.7     8.3    -      -       +      -
    505A  ALA*     4.2    25.0    -      -       +      +
    519A  MSE      6.3     1.3    -      -       -      -
    521A  PHE*     3.6    28.5    -      -       +      -
    542A  ILE*     5.8     1.3    -      -       +      -
    546A  VAL      2.9    17.2    +      -       -      +
    547A  LEU*     3.6     9.4    -      -       +      +
    549A  ALA*     1.3    77.4    -      -       -      +
    551A  LEU*     1.3    57.9    +      -       +      +
    553A  GLN*     3.3     4.3    +      -       -      +
    554A  ALA*     2.9    28.6    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 551 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  GLU*     3.7    44.5    -      -       +      +
    225A  VAL*     5.3     6.5    -      -       +      -
    226A  ALA*     4.6     8.5    -      -       +      +
    229A  LEU*     6.1     1.1    -      -       +      -
    521A  PHE*     4.1    22.7    -      -       +      -
    523A  VAL*     4.4    14.6    -      -       +      -
    533A  LEU*     4.7    11.4    -      -       +      -
    535A  LEU*     6.5     0.9    -      -       +      -
    547A  LEU*     2.9    46.2    +      -       +      +
    548A  ALA*     3.8     6.7    -      -       -      +
    550A  ALA*     1.3    74.0    -      -       -      +
    552A  LYS*     1.3    60.4    +      -       -      +
    554A  ALA*     3.4     5.0    +      -       -      +
    555A  ARG*     2.8    28.8    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 552 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  GLU*     4.7     3.8    -      -       -      +
    548A  ALA      2.9    19.8    +      -       -      +
    549A  ALA*     3.7     8.7    -      -       -      +
    551A  LEU*     1.3    72.8    -      -       -      +
    553A  GLN*     1.3    65.6    +      -       -      +
    555A  ARG*     3.3    15.6    +      -       +      +
    556A  ASP*     3.0    47.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 553 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    345A  VAL*     3.3     9.4    +      -       -      +
    346A  THR*     3.8    21.8    -      -       +      +
    490A  MSE      4.9     3.2    -      -       -      -
    505A  ALA*     3.3    42.0    +      -       -      +
    506A  LEU      4.1     0.6    -      -       -      -
    507A  THR*     2.6    32.1    +      -       -      +
    549A  ALA      2.9    17.2    +      -       -      +
    550A  ALA      3.4     6.1    -      -       -      +
    552A  LYS*     1.3    75.9    -      -       -      +
    554A  ALA*     1.3    62.3    +      -       -      +
    556A  ASP*     3.0    21.0    +      -       +      +
    557A  ALA*     3.1    12.6    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 554 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    488A  ILE*     3.6    12.3    -      -       +      +
    490A  MSE      3.6    35.6    -      -       +      -
    521A  PHE*     4.1     8.3    -      -       +      -
    523A  VAL*     4.5    13.0    -      -       +      -
    550A  ALA      2.9    17.0    +      -       -      +
    551A  LEU*     3.6     6.1    -      -       -      +
    553A  GLN*     1.3    77.6    -      -       -      +
    555A  ARG*     1.3    56.3    +      -       -      +
    557A  ALA*     3.3     4.3    +      -       -      +
    558A  ARG*     3.0    28.3    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 555 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  GLU*     3.5    33.0    +      -       -      +
    527A  LYS      4.0    18.0    +      -       -      -
    551A  LEU      2.8    18.1    +      -       -      +
    552A  LYS*     3.4    15.3    -      -       -      +
    553A  GLN      3.2     0.2    -      -       -      -
    554A  ALA*     1.3    74.9    -      -       -      +
    556A  ASP*     1.3    76.1    +      -       -      +
    558A  ARG*     3.2    22.7    +      -       -      +
    559A  LEU*     3.0    51.5    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASP 556 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    552A  LYS*     3.0    40.2    +      -       -      +
    553A  GLN*     3.0    12.2    +      -       +      +
    555A  ARG*     1.3    89.5    +      -       -      +
    557A  ALA*     1.3    63.2    +      -       -      +
    559A  LEU*     3.3    10.5    +      -       -      +
    560A  HIS*     3.1    22.2    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 557 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    348A  ILE*     3.8    16.6    -      -       +      -
    488A  ILE*     3.9    13.2    -      -       +      -
    507A  THR*     3.8    28.7    -      -       +      -
    553A  GLN      3.1     9.7    +      -       -      +
    554A  ALA*     3.5     9.6    -      -       -      +
    555A  ARG      3.2     0.2    -      -       -      -
    556A  ASP*     1.3    76.9    -      -       -      +
    558A  ARG*     1.3    62.0    +      -       -      +
    560A  HIS*     3.2     4.0    +      -       -      +
    561A  ILE*     3.1    30.1    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 558 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  GLU*     2.5    31.7    +      -       -      -
    486A  ALA*     3.4    27.8    -      -       +      +
    487A  GLY*     4.5     1.6    -      -       -      +
    488A  ILE*     4.7     8.9    -      -       +      +
    523A  VAL*     4.1    14.0    -      -       +      +
    524A  ALA      4.5     2.0    -      -       -      -
    525A  GLY*     3.2    27.0    -      -       -      +
    526A  THR      2.5    33.4    +      -       -      -
    527A  LYS*     4.6     4.6    +      -       -      +
    528A  GLU      5.0     0.2    -      -       -      -
    529A  PHE*     3.4    20.9    +      -       -      +
    530A  VAL*     4.0    10.9    -      -       -      +
    554A  ALA      3.0    13.3    +      -       -      +
    555A  ARG*     3.2    24.2    +      -       -      +
    557A  ALA*     1.3    78.2    -      -       -      +
    559A  LEU*     1.3    60.0    +      -       -      +
    561A  ILE*     3.3    10.9    +      -       -      +
    562A  LEU*     3.0    31.2    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 559 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    526A  THR      4.7     2.0    -      -       -      +
    527A  LYS*     3.7    45.5    -      -       +      +
    555A  ARG*     3.0    57.2    +      -       +      +
    556A  ASP*     3.7     8.3    -      -       -      +
    557A  ALA      3.3     0.2    -      -       -      -
    558A  ARG*     1.3    75.9    -      -       +      +
    560A  HIS*     1.3    66.2    +      -       -      +
    562A  LEU*     3.3    10.6    +      -       +      +
    563A  ASP*     3.2    26.4    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with HIS 560 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    348A  ILE*     3.7    27.1    -      -       +      +
    351A  LEU*     4.0    20.0    -      -       +      +
    556A  ASP      3.1    12.1    +      -       -      +
    557A  ALA*     3.2     8.9    +      -       -      +
    559A  LEU*     1.3    76.0    -      -       -      +
    561A  ILE*     1.3    57.8    +      -       -      +
    563A  ASP*     2.9    34.9    +      -       +      +
    564A  VAL*     3.2    18.0    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 561 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    348A  ILE*     4.4     8.3    -      -       +      -
    351A  LEU*     4.0    25.6    -      -       +      -
    367A  PHE*     4.1    13.9    -      -       +      -
    369A  ARG*     4.8    11.4    -      -       -      +
    468A  CYS*     4.0    14.6    -      -       -      -
    486A  ALA*     4.0     3.8    -      -       +      -
    487A  GLY      3.8    12.6    -      -       -      +
    488A  ILE*     3.6    30.3    -      -       +      -
    557A  ALA      3.1    17.5    +      -       -      +
    558A  ARG*     3.6     7.9    -      -       -      +
    560A  HIS*     1.3    77.1    -      -       -      +
    562A  LEU*     1.3    61.7    +      -       -      +
    564A  VAL*     3.2     3.7    +      -       +      +
    565A  MSE      3.0    39.7    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 562 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    484A  PRO*     3.9    19.1    -      -       +      +
    485A  VAL      3.9     6.7    -      -       -      -
    486A  ALA*     3.4    27.8    -      -       +      +
    525A  GLY      4.2     4.0    -      -       -      +
    526A  THR*     3.9     7.6    -      -       -      +
    527A  LYS*     3.6    50.5    -      -       +      +
    558A  ARG*     3.0    19.4    +      -       -      +
    559A  LEU*     3.6    16.4    -      -       +      +
    560A  HIS      3.2     0.2    -      -       -      -
    561A  ILE*     1.3    76.1    -      -       -      +
    563A  ASP*     1.3    59.5    +      -       -      +
    565A  MSE      3.4    15.3    +      -       +      +
    566A  MSE      2.9    37.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASP 563 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    527A  LYS*     5.2     8.3    -      -       -      -
    559A  LEU*     3.2    15.8    +      -       -      +
    560A  HIS*     2.9    20.2    +      -       -      +
    562A  LEU*     1.3    76.5    -      -       -      +
    564A  VAL*     1.3    65.9    +      -       +      +
    566A  MSE      3.2    15.3    +      -       -      +
    567A  GLU*     3.3    19.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 564 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    351A  LEU*     3.7    40.4    -      -       +      -
    352A  ALA*     4.8     1.6    -      -       -      +
    353A  ALA*     4.2    24.6    -      -       +      +
    367A  PHE*     6.2     2.5    -      -       +      -
    560A  HIS*     3.2    27.3    +      -       +      +
    561A  ILE*     3.2     6.5    +      -       +      +
    563A  ASP*     1.3    75.8    -      -       +      +
    565A  MSE      1.3    63.2    +      -       +      +
    567A  GLU*     3.3    28.7    +      -       -      +
    568A  ALA*     3.7     3.5    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with MSE 565 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    353A  ALA*     4.5     2.7    -      -       +      -
    367A  PHE*     4.9     3.4    -      -       +      -
    468A  CYS*     3.7    22.4    -      -       +      +
    471A  THR*     3.5    28.7    -      -       +      -
    472A  MSE      3.9    34.2    -      -       +      +
    484A  PRO*     4.7     2.0    -      -       +      -
    485A  VAL      3.3    21.8    -      -       -      +
    486A  ALA*     3.7    24.7    -      -       -      -
    561A  ILE*     3.0    25.4    +      -       +      +
    562A  LEU*     3.6    15.0    -      -       +      +
    564A  VAL*     1.3    77.4    -      -       +      +
    566A  MSE      1.3    60.5    +      -       +      +
    568A  ALA*     3.0    20.6    +      -       -      +
    569A  ILE*     3.1    13.4    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with MSE 566 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    471A  THR*     5.9     0.4    -      -       -      -
    475A  LEU*     5.2     3.4    -      -       +      -
    484A  PRO*     3.7    41.7    -      -       +      -
    527A  LYS*     4.3    16.6    -      -       -      +
    562A  LEU*     2.9    28.2    +      -       -      +
    563A  ASP*     3.2     8.0    +      -       -      +
    565A  MSE      1.3    77.6    -      -       -      +
    567A  GLU*     1.3    65.5    +      -       +      +
    568A  ALA      3.2     0.2    -      -       -      -
    569A  ILE*     3.3    29.3    -      -       -      +
    570A  ASP*     3.0    51.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 567 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    563A  ASP*     3.3    15.4    +      -       -      +
    564A  VAL*     3.6    20.3    -      -       -      +
    565A  MSE      3.1     1.0    -      -       -      -
    566A  MSE      1.3    78.4    -      -       -      +
    568A  ALA*     1.3    61.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 568 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    353A  ALA*     3.9    37.9    -      -       +      +
    354A  GLU*     4.2     8.7    -      -       -      -
    355A  VAL*     4.0    13.4    -      -       -      +
    472A  MSE      4.1     8.1    -      -       -      -
    564A  VAL      3.7     1.8    +      -       -      +
    565A  MSE      3.0    10.2    +      -       -      +
    567A  GLU*     1.3    82.3    -      -       -      +
    569A  ILE*     1.3    62.8    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 569 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    355A  VAL*     3.7    21.3    -      -       +      -
    472A  MSE      4.0    27.4    -      -       +      -
    475A  LEU*     3.6    18.1    -      -       +      +
    476A  ASN*     3.4    29.8    -      -       +      +
    565A  MSE      3.1    10.7    +      -       -      +
    566A  MSE      3.3    18.1    -      -       -      +
    567A  GLU      3.5     0.4    -      -       -      -
    568A  ALA*     1.3    80.4    -      -       +      +
    570A  ASP*     1.3    63.7    +      -       -      +
    571A  THR      3.4    16.2    -      -       -      +
    573A  ASP*     3.4    28.9    -      -       -      +
----------------------------------------------------------
 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