Contacts of the helix formed by residues 137 - 161 (chain E) in PDB entry 3ZNI


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 SER 137 (chain E).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    131E  ARG*     2.6    62.4    +      -       -      +
    134E  GLU*     2.9    15.7    +      -       -      +
    135E  GLU      4.4     0.9    -      -       -      +
    136E  GLN*     1.3    82.4    -      -       -      +
    138E  GLN*     1.3    63.2    +      -       -      +
    139E  ASP*     3.7     4.3    +      -       -      -
    140E  ARG*     3.2    15.4    +      -       -      +
    141E  ARG*     3.2    17.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 138 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    131E  ARG*     4.9     0.8    -      -       -      +
    136E  GLN      3.8     0.8    +      -       -      -
    137E  SER*     1.3    70.8    -      -       -      +
    139E  ASP*     1.3    62.2    +      -       -      +
    141E  ARG*     3.0    22.8    +      -       -      +
    142E  ASN*     2.9    55.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASP 139 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124E  LEU*     3.5    19.2    -      -       +      +
    127E  GLU      5.0     0.7    -      -       -      -
    128E  GLY*     3.6    17.2    +      -       -      -
    131E  ARG*     3.4    29.3    +      -       +      +
    132E  MET*     3.7    21.6    -      -       -      +
    137E  SER*     3.2     8.3    -      -       -      +
    138E  GLN*     1.3    78.6    +      -       -      +
    140E  ARG*     1.3    57.8    +      -       -      +
    142E  ASN*     3.3    14.3    +      -       -      +
    143E  LEU*     3.1    20.8    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 140 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64E  LYS      4.8     0.2    +      -       -      -
     65E  LEU*     2.3    42.6    +      -       -      +
     66E  GLN      4.1     5.5    +      -       -      -
     67E  LEU*     3.8    20.8    -      -       -      +
    132E  MET*     2.8    38.8    +      -       -      +
    133E  TYR*     4.0     6.9    +      -       -      +
    134E  GLU      3.7     5.4    -      -       -      +
    135E  GLU*     3.6    47.0    -      -       +      +
    137E  SER*     3.2    21.5    +      -       -      +
    138E  GLN      3.2     0.2    -      -       -      -
    139E  ASP*     1.3    78.6    -      -       -      +
    141E  ARG*     1.3    64.2    +      -       -      +
    143E  LEU*     3.2    20.5    +      -       -      +
    144E  THR*     3.0    28.5    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 141 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135E  GLU      5.5     0.2    +      -       -      -
    137E  SER      3.2    11.5    +      -       -      +
    138E  GLN*     3.0    34.2    +      -       -      +
    140E  ARG*     1.3    76.8    -      -       -      +
    142E  ASN*     1.3    58.8    +      -       -      +
    144E  THR*     3.2    15.0    +      -       -      +
    145E  LYS*     2.9    43.5    +      -       -      +
    262E  ALA      4.3     3.4    +      -       -      -
    263E  PHE*     2.8    37.8    +      -       -      +
    264E  LEU*     4.1     6.6    -      -       -      +
    268E  GLU*     2.9    41.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASN 142 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    120E  ARG*     5.2     7.4    -      -       -      +
    124E  LEU*     3.7    20.2    -      -       +      +
    138E  GLN*     2.9    42.6    +      -       -      +
    139E  ASP*     3.5    16.1    +      -       -      +
    140E  ARG      3.3     0.2    -      -       -      -
    141E  ARG*     1.3    76.8    -      -       -      +
    143E  LEU*     1.3    62.4    +      -       -      +
    145E  LYS*     3.5     9.4    +      -       -      +
    146E  LEU*     3.1    28.7    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 143 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56E  VAL*     5.8     0.7    -      -       +      -
     60E  CYS*     4.2    16.6    -      -       -      -
     65E  LEU*     4.7     3.6    -      -       +      -
     67E  LEU*     4.5    17.9    -      -       +      -
     74E  ILE*     5.6     4.5    -      -       +      -
    121E  ALA*     5.1     8.7    -      -       +      -
    124E  LEU*     3.4    17.0    -      -       +      +
    125E  PHE*     4.1    27.6    -      -       +      -
    132E  MET*     4.0    16.6    -      -       +      -
    139E  ASP      3.1     9.7    +      -       -      +
    140E  ARG*     3.4    23.1    -      -       -      +
    141E  ARG      3.2     0.6    -      -       -      -
    142E  ASN*     1.3    74.6    -      -       -      +
    144E  THR*     1.3    60.0    +      -       -      +
    146E  LEU*     3.2    10.7    +      -       +      +
    147E  SER*     2.9    39.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 144 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72E  PRO*     4.8     2.0    -      -       +      +
    140E  ARG*     3.0    17.7    +      -       -      +
    141E  ARG*     3.2    13.2    +      -       -      +
    143E  LEU*     1.3    77.1    -      -       -      +
    145E  LYS*     1.3    62.0    +      -       -      +
    147E  SER*     3.1     9.7    +      -       -      -
    148E  LEU*     3.0    23.2    +      -       +      +
    265E  THR*     3.6    29.8    -      -       +      +
    268E  GLU*     3.7    25.5    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 145 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    141E  ARG*     2.9    29.1    +      -       -      +
    142E  ASN*     3.6    13.7    -      -       -      +
    144E  THR*     1.3    77.7    -      -       -      +
    146E  LEU*     1.3    64.6    +      -       +      +
    148E  LEU*     3.2     6.4    +      -       +      +
    149E  ILE*     3.0    40.4    +      -       +      +
    224E  CYS*     4.0     9.3    -      -       -      -
    263E  PHE*     3.6    56.8    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 146 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74E  ILE*     6.3     0.2    -      -       +      -
    117E  LYS*     4.0    33.8    -      -       +      +
    120E  ARG*     4.1    17.0    -      -       +      -
    121E  ALA*     3.6    40.4    -      -       +      +
    124E  LEU*     4.2    11.9    -      -       +      -
    142E  ASN*     3.1    19.2    +      -       +      +
    143E  LEU*     3.2    11.9    +      -       +      +
    145E  LYS*     1.3    77.6    -      -       +      +
    147E  SER*     1.3    57.6    +      -       -      +
    149E  ILE*     3.3    13.7    +      -       +      +
    150E  PHE*     2.9    43.6    +      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 147 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72E  PRO*     4.0    21.3    -      -       -      -
     74E  ILE*     3.7    37.5    -      -       -      +
     77E  ILE*     3.6     7.8    -      -       -      +
    143E  LEU*     2.9    24.1    +      -       -      +
    144E  THR*     3.1    13.5    +      -       -      -
    146E  LEU*     1.3    75.7    -      -       -      +
    148E  LEU*     1.3    57.7    +      -       -      +
    150E  PHE*     3.5     0.9    +      -       -      +
    151E  SER*     3.0    27.7    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 148 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72E  PRO*     3.9    22.2    -      -       +      +
    144E  THR*     3.0    12.8    +      -       +      +
    145E  LYS*     3.4    11.4    -      -       -      +
    147E  SER*     1.3    75.5    -      -       -      +
    149E  ILE*     1.3    59.5    +      -       -      +
    151E  SER*     3.1     5.6    +      -       -      -
    152E  HIS*     2.9    61.9    +      -       +      +
    263E  PHE*     3.4    50.7    -      -       +      +
    264E  LEU      4.1     6.5    -      -       -      +
    265E  THR*     4.1    14.8    -      -       +      -
    287E  LEU      6.2     0.2    -      -       -      +
    289E  CYS*     4.1    17.0    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 149 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117E  LYS*     3.9    24.2    -      -       +      -
    145E  LYS*     3.0    32.7    +      -       +      +
    146E  LEU*     3.3    17.7    +      -       +      +
    148E  LEU*     1.3    75.5    -      -       -      +
    150E  PHE*     1.3    58.5    +      -       +      +
    152E  HIS*     3.2     3.8    +      -       -      +
    153E  MET*     2.8    45.5    +      -       -      +
    222E  LEU      4.0    10.3    -      -       -      +
    223E  THR*     3.3    24.2    -      -       -      +
    224E  CYS*     3.7    34.3    -      -       +      -
    263E  PHE*     4.9     1.8    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with PHE 150 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56E  VAL*     5.0     1.1    -      -       +      -
     74E  ILE*     3.6    23.6    -      -       +      -
     77E  ILE*     3.6    20.0    -      -       +      +
     78E  LEU*     3.8    23.8    -      -       +      -
     81E  THR*     4.7     2.3    +      -       -      +
    114E  LEU*     3.8    27.1    -      -       +      -
    117E  LYS*     3.5    47.8    -      -       +      -
    118E  SER*     3.7    11.9    -      -       -      -
    121E  ALA*     4.8     8.3    -      -       +      -
    146E  LEU*     2.9    37.0    +      -       +      +
    147E  SER      3.8     3.8    -      -       -      +
    149E  ILE*     1.3    72.4    -      -       +      +
    151E  SER*     1.3    57.2    +      -       -      +
    153E  MET*     3.3    10.1    +      -       +      +
    154E  LEU*     2.9    30.3    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 151 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72E  PRO*     4.0     9.1    -      -       -      +
     77E  ILE*     3.6    23.5    -      -       -      +
    147E  SER      3.0    15.4    +      -       -      -
    148E  LEU      3.1     8.7    +      -       -      -
    150E  PHE*     1.3    76.4    -      -       -      +
    152E  HIS*     1.3    62.7    +      -       -      +
    154E  LEU*     3.3     5.6    +      -       -      +
    155E  ALA*     3.1    22.2    +      -       -      +
    289E  CYS*     3.3    27.1    +      -       -      -
    292E  LEU*     5.2     0.6    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with HIS 152 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    148E  LEU*     2.9    49.6    +      -       +      +
    149E  ILE      3.7     3.8    -      -       -      +
    151E  SER*     1.3    78.2    +      -       -      +
    153E  MET*     1.3    58.7    +      -       -      +
    155E  ALA*     3.4     2.9    +      -       -      +
    156E  GLU*     2.9    28.6    +      -       -      +
    222E  LEU*     3.6    46.9    -      -       +      +
    223E  THR*     4.3    14.2    -      -       +      +
    231E  PHE*     4.2     4.1    -      -       +      -
    263E  PHE*     4.4    10.4    -      +       -      -
    287E  LEU*     5.5     5.6    -      -       +      +
    288E  SER      5.2     0.7    -      -       -      -
    289E  CYS*     4.7    11.1    +      -       -      -
    292E  LEU*     3.7    36.1    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with MET 153 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110E  TYR*     3.7    34.5    -      -       +      +
    113E  SER*     3.7    27.4    -      -       -      -
    114E  LEU*     3.8    20.0    -      -       +      +
    117E  LYS*     4.5    10.1    -      -       -      -
    149E  ILE*     2.8    35.1    +      -       -      +
    150E  PHE*     3.6    21.3    -      -       +      +
    152E  HIS*     1.3    73.6    -      -       -      +
    154E  LEU*     1.3    61.1    +      -       -      +
    156E  GLU*     3.2     5.9    +      -       -      +
    157E  ILE*     2.9    30.7    +      -       -      +
    223E  THR*     3.7    29.6    -      -       +      +
    225E  ASN*     6.0     0.2    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 154 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77E  ILE*     4.0    21.3    -      -       +      +
     80E  ASP*     3.8    27.4    -      -       +      +
     81E  THR*     3.5    34.1    +      -       -      +
     84E  HIS*     4.7     1.6    -      -       +      -
    110E  TYR*     5.1     0.9    -      -       -      -
    150E  PHE      2.9    16.1    +      -       -      +
    151E  SER*     3.6     5.8    -      -       -      +
    152E  HIS      3.3     0.2    -      -       -      -
    153E  MET*     1.3    76.6    -      -       -      +
    155E  ALA*     1.3    62.3    +      -       -      +
    157E  ILE*     3.2    17.6    -      -       +      +
    158E  LYS*     3.2    51.8    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 155 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    151E  SER      3.1    11.1    +      -       -      +
    152E  HIS      3.7     2.9    -      -       -      +
    154E  LEU*     1.3    77.5    -      -       -      +
    156E  GLU*     1.3    63.8    +      -       -      +
    158E  LYS*     3.6     7.6    +      -       -      +
    159E  ALA*     3.2    23.0    +      -       -      +
    231E  PHE*     3.8     7.8    -      -       +      -
    292E  LEU*     3.5    31.9    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 156 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106E  TYR*     2.6    35.6    +      -       +      +
    110E  TYR*     4.5     6.4    -      -       -      -
    152E  HIS      2.9    18.1    +      -       -      +
    153E  MET*     3.5     6.1    -      -       -      +
    154E  LEU      3.1     0.2    -      -       -      -
    155E  ALA*     1.3    77.8    -      -       -      +
    157E  ILE*     1.3    57.5    +      -       -      +
    159E  ALA*     3.1     2.9    +      -       -      +
    160E  ILE*     2.9    34.6    +      -       +      +
    191E  ILE*     5.7     0.7    -      -       -      +
    223E  THR*     3.9    16.6    +      -       +      +
    225E  ASN*     5.5     3.1    +      -       -      -
    229E  SER*     2.6    28.6    +      -       -      +
    231E  PHE*     3.6    27.5    -      -       +      -
    232E  GLU*     3.8    16.1    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 157 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     81E  THR*     5.6     0.7    -      -       +      +
     84E  HIS*     3.6    25.0    +      -       +      -
     85E  LEU*     4.8     2.0    -      -       +      -
     88E  ILE*     3.9    13.7    -      -       +      -
    106E  TYR*     3.6    29.5    +      -       +      -
    107E  PHE*     4.7     2.9    -      -       +      -
    110E  TYR*     3.7    41.5    -      -       +      +
    153E  MET      2.9    15.3    +      -       -      +
    154E  LEU*     3.2    24.5    -      -       +      +
    156E  GLU*     1.3    75.4    -      -       -      +
    158E  LYS*     1.3    56.5    +      -       -      +
    160E  ILE*     4.5     0.9    -      -       -      +
    161E  PHE*     2.7    48.2    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 158 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80E  ASP*     4.7    14.3    +      -       -      +
     84E  HIS*     3.8    37.5    -      -       +      +
    154E  LEU*     3.2    46.1    +      -       +      +
    155E  ALA*     3.9     7.0    -      -       -      +
    157E  ILE*     1.3    75.8    -      -       -      +
    159E  ALA*     1.3    62.0    +      -       -      +
    160E  ILE      3.4     0.2    -      -       -      -
    162E  PRO*     3.3    25.1    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 159 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    155E  ALA      3.2    17.2    +      -       -      +
    156E  GLU      3.1     4.1    +      -       -      +
    158E  LYS*     1.3    77.8    -      -       -      +
    160E  ILE*     1.3    65.3    +      -       +      +
    162E  PRO*     3.6    10.6    -      -       -      +
    167E  GLN*     5.1     3.6    -      -       -      +
    171E  PHE*     4.2    19.0    -      -       +      +
    231E  PHE*     3.5    30.3    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 160 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106E  TYR*     3.9    26.7    -      -       +      -
    156E  GLU*     2.9    25.7    +      -       +      +
    157E  ILE      4.2     0.4    -      -       -      +
    159E  ALA*     1.3    80.3    -      -       -      +
    161E  PHE*     1.3    61.2    +      -       +      +
    162E  PRO*     3.3     7.1    -      -       -      +
    166E  PHE*     3.7    26.9    -      -       +      -
    167E  GLN*     2.8    31.7    +      -       -      -
    168E  GLY*     3.3    11.7    +      -       -      +
    171E  PHE*     4.3    10.1    -      -       +      -
    190E  THR*     3.8    23.3    -      -       +      -
    229E  SER*     5.7     0.9    -      -       -      -
    230E  VAL*     4.1    17.7    -      -       +      -
    231E  PHE*     4.4     8.7    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with PHE 161 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84E  HIS*     2.8    18.4    +      -       -      +
     88E  ILE*     3.8    24.7    -      -       +      -
     92E  TYR*     3.9     5.2    -      +       -      -
    101E  LEU*     3.8    31.2    -      -       +      -
    104E  ASN*     4.4     4.0    -      -       -      -
    106E  TYR*     3.9    20.4    -      +       -      -
    107E  PHE*     4.2    13.7    -      +       +      -
    157E  ILE*     2.7    34.3    +      -       +      +
    160E  ILE*     1.3    81.6    -      -       +      +
    162E  PRO*     1.3    66.7    -      -       -      +
    164E  GLY      2.9    16.3    +      -       -      -
    165E  GLN      3.3     7.6    -      -       -      -
    166E  PHE*     3.4    52.0    -      +       +      -
----------------------------------------------------------
 Back to top of page


A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il