Contacts of the helix formed by residues 126 - 150 (chain L) in PDB entry 1QGH


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 ASP 126 (chain L).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114B  LYS*     2.5    36.8    +      -       -      +
    117B  ILE*     3.6    19.5    -      -       +      +
    133B  ILE*     3.7    29.4    -      -       +      +
    136B  LYS*     5.2     4.5    -      -       -      +
    124L  GLY*     3.0     9.7    +      -       -      +
    125L  ASP*     1.3    71.8    +      -       -      +
    127L  VAL*     1.3    65.2    +      -       +      +
    129L  ASN*     3.2     9.9    -      -       -      +
    130L  ASP*     3.0    24.3    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 127 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117B  ILE*     5.7     0.2    -      -       +      -
    133B  ILE*     3.7    18.6    -      -       +      +
    136B  LYS*     3.7    25.2    -      -       +      +
    137B  ALA*     3.5    44.2    -      -       +      +
    140B  ASP*     4.1     2.0    -      -       -      +
     63L  ARG*     3.2    41.3    -      -       -      +
    125L  ASP*     3.2     1.2    +      -       -      -
    126L  ASP*     1.3    78.6    -      -       +      +
    128L  THR*     1.3    62.9    +      -       -      +
    130L  ASP*     3.1     5.9    +      -       -      +
    131L  MET*     3.1    23.5    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 128 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9L  THR*     4.0     5.2    -      -       +      +
     13L  LEU*     3.7    37.5    -      -       +      +
     63L  ARG*     2.8    21.5    +      -       -      +
     67L  ILE*     4.6     0.2    -      -       -      +
    120L  THR*     3.5    14.4    -      -       -      +
    125L  ASP*     2.5    31.2    +      -       -      -
    127L  VAL*     1.3    75.6    -      -       -      +
    129L  ASN*     1.3    64.1    +      -       -      +
    131L  MET*     3.0    22.4    +      -       +      +
    132L  LEU*     3.0    20.8    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASN 129 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117L  ILE*     3.1    27.5    +      -       -      +
    120L  THR*     2.9    37.0    +      -       +      +
    121L  ASP*     4.0    15.0    +      -       -      +
    125L  ASP      3.0    10.9    +      -       -      +
    126L  ASP*     3.2    15.1    -      -       -      +
    128L  THR*     1.3    77.7    -      -       -      +
    130L  ASP*     1.3    66.6    +      -       -      +
    132L  LEU*     3.4     3.4    +      -       -      +
    133L  ILE*     3.0    39.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASP 130 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    130B  ASP*     3.5    24.8    -      -       -      +
    133B  ILE*     3.8    26.0    -      -       +      +
    134B  ALA*     5.4     0.9    +      -       -      +
    130G  ASP*     3.4    27.0    -      -       -      +
    126L  ASP      3.0    10.3    +      -       -      +
    127L  VAL      3.1     6.5    +      -       -      +
    129L  ASN*     1.3    83.0    -      -       -      +
    131L  MET*     1.3    67.6    +      -       -      +
    133L  ILE*     3.3     7.4    +      -       -      +
    134L  ALA*     3.0    21.8    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with MET 131 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13L  LEU*     4.3     4.0    -      -       +      -
     59L  GLU*     3.8    17.7    -      -       -      +
     60L  VAL*     4.1    18.6    -      -       +      -
     63L  ARG*     3.8    32.5    -      -       +      -
    127L  VAL*     3.1    18.8    +      -       +      +
    128L  THR*     3.0    20.8    +      -       +      +
    130L  ASP*     1.3    75.9    -      -       -      +
    132L  LEU*     1.3    87.4    +      -       +      +
    134L  ALA*     3.1     8.7    +      -       -      +
    135L  PHE*     2.9    44.4    +      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 132 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12L  PHE*     4.0    32.5    -      -       +      -
     13L  LEU*     4.3     3.8    -      -       +      -
     16L  GLN*     6.0     0.7    -      -       +      -
     60L  VAL*     5.2     2.7    -      -       +      -
    113L  TYR*     4.0    18.4    -      -       +      +
    116L  GLY      4.0    20.0    -      -       -      +
    117L  ILE*     3.8    15.7    -      -       +      +
    120L  THR*     4.4     4.0    -      -       +      +
    128L  THR*     3.0    30.4    +      -       +      +
    129L  ASN      3.6     4.3    -      -       -      +
    131L  MET*     1.3   104.2    -      -       +      +
    133L  ILE*     1.3    62.4    +      -       -      +
    135L  PHE*     3.2    16.0    +      -       +      +
    136L  LYS*     2.8    24.1    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 133 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126G  ASP*     3.6    40.6    -      -       +      +
    127G  VAL*     3.5    15.5    -      -       +      +
    130G  ASP*     3.9    21.8    -      -       +      +
    117L  ILE*     3.8    25.1    -      -       +      -
    129L  ASN*     3.0    35.3    +      -       -      +
    130L  ASP*     3.7    16.6    -      -       -      +
    131L  MET      3.2     0.2    -      -       -      -
    132L  LEU*     1.3    73.7    -      -       -      +
    134L  ALA*     1.3    58.7    +      -       -      +
    136L  LYS*     3.0     4.2    +      -       -      +
    137L  ALA*     2.8    27.5    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 134 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    130G  ASP*     5.5     0.4    +      -       -      -
    130L  ASP      3.0    13.4    +      -       -      +
    131L  MET*     3.4     9.6    -      -       -      +
    133L  ILE*     1.3    77.7    -      -       -      +
    135L  PHE*     1.3    69.9    +      -       +      +
    137L  ALA*     3.2    17.9    +      -       -      +
    138L  SER*     3.3    10.7    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with PHE 135 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56L  GLN*     3.5    47.6    +      -       +      +
     59L  GLU*     3.7    34.5    -      -       +      -
     60L  VAL*     3.5    26.9    -      -       +      -
    113L  TYR*     3.4    28.0    -      +       +      -
    131L  MET*     2.9    37.2    +      -       +      -
    132L  LEU*     3.6     8.1    -      -       +      +
    134L  ALA*     1.3    82.4    -      -       +      +
    136L  LYS*     1.3    65.3    +      -       -      +
    138L  SER*     3.0     6.8    +      -       -      -
    139L  ILE*     2.9    25.1    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 136 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63G  ARG*     4.6     5.6    -      -       -      +
    125G  ASP*     5.5     1.3    +      -       -      -
    126G  ASP*     5.1     4.0    -      -       -      +
    127G  VAL*     3.7    20.8    -      -       +      +
    110L  ARG*     4.1    34.1    -      -       +      +
    113L  TYR*     4.2     6.0    -      -       +      -
    114L  LYS*     4.6    15.9    -      -       +      +
    117L  ILE*     4.0    22.0    -      -       +      -
    132L  LEU      2.8    13.5    +      -       -      +
    133L  ILE      3.0     8.5    +      -       -      +
    135L  PHE*     1.3    76.3    -      -       -      +
    137L  ALA*     1.3    64.2    +      -       -      +
    139L  ILE*     3.1     9.8    +      -       +      +
    140L  ASP*     2.9    54.5    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 137 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63G  ARG*     5.0     1.0    +      -       -      -
    127G  VAL*     3.6    30.3    -      -       +      +
    131G  MET*     6.4     0.9    -      -       +      -
    133L  ILE*     2.8    11.3    +      -       +      +
    134L  ALA*     3.4    13.9    -      -       -      +
    135L  PHE      3.1     0.4    -      -       -      -
    136L  LYS*     1.3    76.4    -      -       -      +
    138L  SER*     1.3    63.2    +      -       -      +
    140L  ASP*     3.5     4.7    +      -       -      +
    141L  LYS*     3.3    18.2    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 138 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52L  GLU*     2.6    28.9    +      -       -      -
     56L  GLN*     4.8     1.9    +      -       -      -
    134L  ALA      3.3     6.8    +      -       -      -
    135L  PHE*     3.0    11.0    +      -       -      -
    137L  ALA*     1.3    78.9    -      -       -      +
    139L  ILE*     1.3    67.7    +      -       -      +
    141L  LYS*     3.1     9.8    +      -       -      +
    142L  HIS*     2.9    36.8    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 139 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53L  PHE*     3.9    28.9    -      -       +      -
     56L  GLN*     4.4     2.0    -      -       -      +
    106L  LEU*     3.7    29.2    -      -       +      +
    109L  LEU*     4.2    16.2    -      -       +      -
    110L  ARG*     3.9    13.2    -      -       +      +
    113L  TYR*     3.9    31.6    -      -       +      -
    135L  PHE      2.9    15.0    +      -       -      +
    136L  LYS*     3.6     7.4    -      -       -      +
    138L  SER*     1.3    75.1    -      -       -      +
    140L  ASP*     1.3    54.1    +      -       -      +
    142L  HIS*     3.0    11.2    +      -       -      +
    143L  ILE*     2.7    51.8    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASP 140 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63G  ARG*     2.9    32.8    +      -       -      +
     66G  ALA*     4.0    15.9    -      -       +      +
     67G  ILE*     6.1     0.2    -      -       -      -
    127G  VAL*     4.2     1.7    -      -       -      +
    110L  ARG*     3.1    34.7    +      -       -      +
    136L  LYS*     2.9    42.1    +      -       -      +
    137L  ALA      3.6     3.8    -      -       -      +
    139L  ILE*     1.3    76.3    -      -       -      +
    141L  LYS*     1.3    57.8    +      -       -      +
    143L  ILE*     3.2     7.6    +      -       -      +
    144L  TRP*     2.9    27.4    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 141 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43E  HIS*     5.4     1.8    +      -       -      -
     62G  GLU*     2.9    32.0    +      -       +      +
     66G  ALA*     4.8     4.5    -      -       -      -
    137L  ALA      3.3     8.9    +      -       -      +
    138L  SER*     3.1    11.9    +      -       -      +
    140L  ASP*     1.3    78.2    -      -       -      +
    142L  HIS*     1.3    66.2    +      -       +      +
    144L  TRP*     3.1    24.0    +      -       +      +
    145L  MET*     3.0    45.2    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with HIS 142 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45L  LYS*     4.5     5.3    +      -       -      -
     49L  LEU*     3.7    21.9    -      -       +      +
     52L  GLU*     2.8    28.7    +      -       -      -
     53L  PHE*     4.0    22.4    -      +       -      -
    106L  LEU*     4.0    17.5    -      -       +      -
    138L  SER*     2.9    35.5    +      -       -      -
    139L  ILE*     3.2     7.0    -      -       -      +
    141L  LYS*     1.3    77.0    -      -       +      +
    143L  ILE*     1.3    59.4    +      -       -      +
    145L  MET*     3.1    21.3    +      -       +      +
    146L  PHE*     2.8    44.8    +      +       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 143 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66G  ALA      6.1     0.4    -      -       -      +
    103L  VAL*     4.9     4.9    -      -       +      +
    106L  LEU*     3.8    22.2    -      -       +      -
    107L  GLU*     3.9    26.7    -      -       +      +
    110L  ARG*     3.8    35.7    -      -       -      +
    139L  ILE*     2.7    40.4    +      -       +      +
    140L  ASP*     3.5     7.2    -      -       -      +
    142L  HIS*     1.3    74.1    -      -       -      +
    144L  TRP*     1.3    64.2    +      -       -      +
    146L  PHE*     4.6     1.3    -      -       -      +
    147L  LYS*     3.1    30.1    +      -       +      +
    154L  PRO*     3.9    23.8    -      -       +      +
    155L  LEU*     5.3     1.3    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with TRP 144 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31E  HIS      4.6     0.4    -      -       -      -
     32E  TRP*     4.0    12.7    +      -       -      -
     34E  MET      5.5     0.6    +      -       -      -
     39E  PHE*     4.0    17.0    -      +       -      -
     43E  HIS*     3.6    27.4    -      +       -      -
     62G  GLU*     3.7    40.2    -      -       +      -
     65G  LEU*     3.7    34.5    -      -       +      +
     66G  ALA*     4.0    19.5    -      -       +      -
    140L  ASP      2.9    13.4    +      -       -      +
    141L  LYS*     3.1    20.4    +      -       +      +
    143L  ILE*     1.3    77.5    -      -       -      +
    145L  MET*     1.3    80.4    +      -       +      +
    147L  LYS*     3.9     1.4    -      -       -      +
    148L  ALA*     3.0    33.5    +      -       +      +
    152L  LYS      5.2     0.2    -      -       -      +
    154L  PRO*     3.9    28.5    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with MET 145 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39E  PHE*     3.6    33.5    -      -       +      -
     40E  PHE*     3.8    17.7    -      -       +      -
     43E  HIS*     4.6    11.2    -      -       -      -
     45L  LYS*     4.1    14.4    -      -       -      +
    141L  LYS*     3.0    41.4    +      -       +      +
    142L  HIS*     3.8    25.1    -      -       +      +
    144L  TRP*     1.3   104.5    -      -       +      +
    146L  PHE*     1.3    62.8    +      -       +      +
    148L  ALA*     3.3     2.8    +      -       -      +
    149L  PHE*     3.0    21.5    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with PHE 146 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40E  PHE*     3.4    32.1    -      +       -      -
     42L  LEU*     4.6     1.3    -      -       +      -
     45L  LYS*     3.8    21.5    -      -       +      -
     46L  MET*     3.5    33.7    -      -       +      -
     49L  LEU*     4.0    10.5    -      -       +      -
     99L  MET*     3.7    26.7    -      -       +      +
    102L  LEU*     3.8    16.6    -      -       +      -
    103L  VAL*     3.4    24.2    -      -       +      -
    106L  LEU*     4.3     5.8    -      -       +      -
    142L  HIS*     2.8    42.7    +      -       +      +
    145L  MET*     1.3    73.6    -      -       +      +
    147L  LYS*     1.3    63.3    +      -       -      +
    149L  PHE*     3.2     6.0    +      -       +      +
    150L  LEU*     3.0    26.3    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 147 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103L  VAL*     3.7    21.8    -      -       +      -
    107L  GLU*     3.3    17.4    +      -       -      -
    143L  ILE*     3.1    23.2    +      -       +      +
    144L  TRP      3.9     2.2    -      -       -      +
    146L  PHE*     1.3    72.6    -      -       -      +
    148L  ALA*     1.3    68.0    +      -       -      +
    150L  LEU*     2.9    22.0    +      -       +      +
    152L  LYS*     2.9    34.6    +      -       +      +
    153L  ALA      3.1    29.4    -      -       -      +
    154L  PRO*     3.3    11.9    -      -       +      +
    156L  GLU*     2.9    49.3    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 148 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34E  MET      3.9     9.9    -      -       -      +
     35E  ARG*     3.3    11.5    -      -       +      +
     36E  GLY      2.8    29.4    +      -       -      -
     39E  PHE*     3.7    27.6    -      -       +      -
    144L  TRP*     3.0    25.1    +      -       +      +
    145L  MET      3.6     5.2    -      -       -      +
    146L  PHE      3.3     0.2    -      -       -      -
    147L  LYS*     1.3    76.8    -      -       -      +
    149L  PHE*     1.3    52.6    +      -       -      +
    151L  GLY      2.9    10.1    +      -       -      +
    152L  LYS      3.6    10.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with PHE 149 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36E  GLY      3.2    27.5    -      -       -      -
     37E  HIS*     3.2    62.0    +      -       +      -
     39E  PHE*     4.1     3.5    -      -       +      +
     40E  PHE*     3.7    28.7    -      +       +      -
     38L  ASN*     4.0     4.7    -      -       +      -
     42L  LEU*     3.4    28.7    -      -       +      -
     95L  MET*     3.9     7.9    -      -       +      -
     96L  ASP*     3.7    17.3    -      -       -      -
     99L  MET*     3.5    30.5    -      -       +      -
    145L  MET      3.0    13.7    +      -       -      +
    146L  PHE*     3.3    10.1    -      +       -      +
    148L  ALA*     1.3    77.6    -      -       -      +
    150L  LEU*     1.3    65.4    +      -       +      +
    151L  GLY      3.2     0.4    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 150 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37E  HIS*     5.2     3.1    -      -       -      -
     96L  ASP*     3.8    47.5    -      -       +      +
     99L  MET*     4.0    13.2    -      -       +      -
    100L  GLU*     3.8    37.9    -      -       +      +
    103L  VAL*     4.4    12.8    -      -       +      -
    146L  PHE      3.0    15.4    +      -       -      +
    147L  LYS*     2.9    16.1    +      -       +      +
    149L  PHE*     1.3    82.5    -      -       +      +
    151L  GLY*     1.3    60.0    +      -       -      +
    152L  LYS*     3.5    18.7    +      -       +      +
----------------------------------------------------------
 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