Contacts of the helix formed by residues 177 - 203 (chain B) in PDB entry 1IZO


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 GLY 177 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176B  VAL*     1.3    80.7    -      -       -      +
    178B  PRO*     1.3    65.9    -      -       -      -
    180B  HIS*     2.7    30.8    +      -       -      +
    181B  TRP*     2.9    22.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with PRO 178 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176B  VAL      3.9     3.6    -      -       -      +
    177B  GLY*     1.3    81.3    -      -       -      -
    179B  ARG*     1.3    64.0    +      -       -      +
    181B  TRP*     3.2    10.0    +      -       +      +
    182B  LYS*     3.1    28.3    +      -       -      +
    185B  ARG*     5.0     1.4    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 179 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168B  ASP      4.4     1.4    -      -       -      +
    171B  ASP*     3.0    39.0    +      -       +      +
    172B  ALA*     3.4    14.6    -      -       -      +
    174B  GLY      3.9     1.8    +      -       -      -
    175B  ALA*     3.2    34.1    -      -       +      +
    176B  VAL      4.0     4.2    +      -       -      +
    177B  GLY      3.3     0.8    -      -       -      -
    178B  PRO*     1.3    81.1    -      -       -      +
    180B  HIS*     1.3    62.6    +      -       -      +
    182B  LYS*     3.4    21.4    +      -       +      +
    399B  ARG*     3.4    30.3    -      -       -      +
    400B  MET      2.3    43.9    +      -       -      +
    401B  PRO*     3.8     1.6    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with HIS 180 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73B  ARG*     3.4    54.1    +      -       +      +
     77B  SER*     4.0    10.5    -      -       -      -
    172B  ALA*     3.1    31.6    +      -       -      +
    173B  PHE      5.7     0.2    -      -       -      -
    175B  ALA*     3.6    14.1    -      -       -      +
    176B  VAL      3.9     8.2    +      -       -      -
    177B  GLY      2.7    17.6    +      -       -      +
    179B  ARG*     1.3    73.2    -      -       -      +
    181B  TRP*     1.3    68.9    +      +       -      +
    183B  GLY      3.1    11.3    +      -       -      -
    184B  ARG*     2.5    49.0    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with TRP 181 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    177B  GLY*     2.9    20.4    +      -       -      +
    178B  PRO*     3.6    12.3    -      -       +      +
    180B  HIS*     1.3    81.2    -      +       -      +
    182B  LYS*     1.3    64.0    +      -       -      +
    184B  ARG*     3.0    41.6    +      -       +      +
    185B  ARG*     3.0    52.7    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 182 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168B  ASP*     3.4    36.9    +      -       +      +
    178B  PRO*     3.1    18.8    +      -       -      +
    179B  ARG*     3.6    15.3    -      -       +      +
    180B  HIS      3.1     0.8    -      -       -      -
    181B  TRP*     1.3    75.5    -      -       -      +
    183B  GLY*     1.3    58.9    +      -       -      +
    185B  ARG*     3.2    19.1    +      -       -      +
    186B  ALA*     2.9    29.5    +      -       -      +
    189B  ARG*     4.8     1.7    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLY 183 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77B  SER*     4.6     7.0    -      -       -      -
    168B  ASP      3.4    26.7    +      -       -      -
    169B  MET*     3.9     7.0    -      -       -      +
    172B  ALA*     3.8     7.2    -      -       -      -
    179B  ARG      3.7     1.4    +      -       -      -
    180B  HIS      3.1     8.2    +      -       -      -
    182B  LYS*     1.3    80.1    -      -       -      +
    184B  ARG*     1.3    61.9    +      -       -      +
    186B  ALA*     3.9     1.2    -      -       -      +
    187B  ARG*     3.1    30.5    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 184 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73B  ARG*     4.4    11.4    -      -       -      +
     76B  LYS*     3.4    56.3    -      -       -      +
     77B  SER*     4.8     0.2    -      -       -      +
    180B  HIS*     2.5    63.5    +      -       +      +
    181B  TRP*     3.0    41.6    +      -       +      +
    183B  GLY*     1.3    78.2    -      -       -      +
    185B  ARG*     1.3    58.8    +      -       -      +
    187B  ARG*     4.1     0.5    -      -       -      +
    188B  PRO*     3.0    23.9    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 185 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    178B  PRO      5.0     1.0    +      -       -      -
    181B  TRP*     3.0    50.4    +      -       +      +
    182B  LYS*     4.0    29.3    -      -       -      +
    184B  ARG*     1.3    77.0    -      -       -      +
    186B  ALA*     1.3    67.3    +      -       -      +
    187B  ARG      3.4     0.4    -      -       -      -
    188B  PRO*     3.4    10.6    -      -       -      +
    189B  ARG*     3.4    33.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 186 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    165B  ASP*     3.4    41.2    -      -       +      +
    168B  ASP*     4.0     5.6    -      -       +      -
    169B  MET*     4.1     6.1    -      -       +      -
    182B  LYS      2.9    17.9    +      -       -      +
    183B  GLY      3.4     2.9    +      -       -      +
    185B  ARG*     1.3    78.9    -      -       -      +
    187B  ARG*     1.3    64.6    +      -       -      +
    189B  ARG*     3.0    20.1    +      -       -      +
    190B  ALA*     2.9    23.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 187 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75B  GLN      4.1     1.8    -      -       -      -
     76B  LYS*     3.2    22.2    -      -       -      +
     77B  SER      2.9    26.3    +      -       -      +
     78B  LEU      2.9    22.4    +      -       -      -
     79B  PHE      3.3     9.1    +      -       -      -
     80B  GLY*     3.3    23.0    -      -       -      +
    169B  MET*     3.8    19.6    -      -       -      +
    183B  GLY      3.1    13.7    +      -       -      +
    186B  ALA*     1.3    76.8    -      -       -      +
    188B  PRO*     1.3    68.5    -      -       +      +
    190B  ALA*     3.2     1.6    +      -       -      +
    191B  GLU*     2.8    79.9    +      -       -      +
    235B  ILE*     4.1     9.5    -      -       -      +
    238B  ILE*     3.7    16.9    -      -       -      +
    239B  ASN*     4.4     0.6    +      -       -      -
    242B  ARG*     3.1    16.2    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with PRO 188 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    184B  ARG      3.0    28.0    -      -       -      +
    185B  ARG*     3.4     9.4    -      -       -      +
    187B  ARG*     1.3    88.9    -      -       +      +
    189B  ARG*     1.3    62.5    +      -       +      +
    191B  GLU*     4.0    11.6    -      -       +      +
    192B  GLU*     3.0    39.6    +      -       +      +
    231B  ARG*     5.4     3.1    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 189 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    161B  GLU*     5.4     8.7    +      -       -      +
    162B  ARG*     4.1     8.9    +      -       -      +
    165B  ASP*     2.7    42.4    +      -       -      +
    168B  ASP*     5.0     5.1    +      -       -      -
    182B  LYS      4.8     1.6    +      -       -      -
    185B  ARG*     3.4    35.1    +      -       -      +
    186B  ALA*     3.0    20.7    +      -       -      +
    188B  PRO*     1.3    78.6    -      -       +      +
    190B  ALA*     1.3    64.1    +      -       -      +
    192B  GLU*     3.9     6.5    -      -       -      +
    193B  TRP*     3.1    25.5    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 190 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    162B  ARG*     4.9     2.0    -      -       -      +
    165B  ASP*     4.5     5.8    +      -       +      +
    166B  PHE*     4.6     9.0    -      -       +      -
    169B  MET*     3.7    31.6    -      -       +      -
    186B  ALA      2.9     8.3    +      -       -      +
    187B  ARG      3.7     2.5    -      -       -      +
    189B  ARG*     1.3    77.5    -      -       -      +
    191B  GLU*     1.3    57.8    +      -       -      +
    193B  TRP*     3.5    13.4    +      -       +      +
    194B  ILE*     2.9    34.5    +      -       -      +
    238B  ILE*     3.5    13.7    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 191 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80B  GLY*     4.1     3.6    -      -       -      -
     81B  VAL      4.7     1.2    +      -       -      -
    187B  ARG*     2.8    67.1    +      -       -      +
    188B  PRO*     4.0     7.8    -      -       +      +
    190B  ALA*     1.3    73.7    -      -       -      +
    192B  GLU*     1.3    59.5    +      -       -      +
    194B  ILE*     3.3     0.7    +      -       -      -
    195B  GLU*     2.8    32.9    +      -       -      +
    231B  ARG*     3.1    35.2    +      -       -      +
    234B  ALA*     4.0     4.9    -      -       +      +
    235B  ILE*     3.5    25.2    -      -       +      +
    238B  ILE*     3.7    11.4    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 192 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188B  PRO*     3.0    30.3    +      -       -      +
    189B  ARG*     3.9     4.9    -      -       -      +
    191B  GLU*     1.3    75.1    -      -       -      +
    193B  TRP*     1.3    62.9    +      -       -      +
    195B  GLU*     3.3     4.6    +      -       -      +
    196B  VAL*     3.2    29.8    +      -       +      +
    231B  ARG*     3.3    24.4    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with TRP 193 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    147B  CYS*     4.2    15.0    -      -       -      -
    152B  VAL*     4.1     5.4    -      -       +      -
    153B  PRO      3.8    14.0    +      -       -      -
    154B  LEU*     3.9    17.9    -      -       +      -
    158B  GLU*     4.1     7.5    +      -       -      -
    162B  ARG*     3.3    63.3    -      -       +      +
    166B  PHE*     4.0    22.4    -      +       -      -
    189B  ARG      3.1    15.1    +      -       -      +
    190B  ALA*     3.5    11.0    -      -       +      +
    192B  GLU*     1.3    81.3    -      -       -      +
    194B  ILE*     1.3    82.6    +      -       +      +
    196B  VAL*     3.6     5.6    +      -       -      +
    197B  MET*     3.0    44.1    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 194 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152B  VAL*     4.0    13.0    -      -       +      -
    190B  ALA      2.9    20.7    +      -       -      +
    193B  TRP*     1.3   101.1    -      -       +      +
    195B  GLU*     1.3    66.0    +      -       -      +
    197B  MET*     3.1    27.1    +      -       +      +
    198B  ILE*     3.0    20.0    +      -       +      +
    234B  ALA*     3.7    27.6    -      -       +      +
    237B  LEU*     3.6    25.6    -      -       +      -
    238B  ILE*     3.9    15.3    -      -       +      -
    241B  LEU*     4.0    11.7    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 195 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    191B  GLU      2.8    22.5    +      -       -      +
    192B  GLU*     3.3     5.4    +      -       -      +
    194B  ILE*     1.3    73.7    -      -       -      +
    196B  VAL*     1.3    64.5    +      -       +      +
    198B  ILE*     3.2     3.8    +      -       -      +
    199B  GLU*     2.9    38.4    +      -       -      +
    230B  SER*     2.8    30.9    -      -       -      -
    231B  ARG*     2.7    48.3    +      -       -      +
    234B  ALA*     3.5    14.0    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 196 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    192B  GLU*     3.2    16.9    +      -       +      +
    193B  TRP*     4.1     5.2    -      -       -      +
    195B  GLU*     1.3    78.5    -      -       +      +
    197B  MET*     1.3    55.0    +      -       +      +
    199B  GLU*     3.3    15.4    +      -       -      +
    200B  ASP*     2.7    52.4    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with MET 197 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152B  VAL*     3.5    26.2    -      -       -      -
    153B  PRO*     3.7    28.3    -      -       +      +
    193B  TRP*     3.0    52.5    +      -       +      +
    194B  ILE*     3.1    19.7    +      -       +      +
    196B  VAL*     1.3    77.5    -      -       +      +
    198B  ILE*     1.3    59.6    +      -       -      +
    200B  ASP*     3.2     4.5    +      -       -      +
    201B  ALA*     2.8    30.3    +      -       -      +
    206B  LEU*     3.7    25.5    -      -       +      +
    214B  LEU*     4.6    10.8    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 198 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    194B  ILE*     3.0    19.3    +      -       +      +
    195B  GLU      3.5     7.4    -      -       -      +
    197B  MET*     1.3    74.3    -      -       -      +
    199B  GLU*     1.3    64.7    +      -       -      +
    201B  ALA*     3.0     7.5    +      -       -      +
    202B  ARG*     2.9    55.5    +      -       -      +
    214B  LEU*     3.9    16.6    -      -       +      +
    217B  MET*     4.4     2.9    -      -       +      -
    218B  ALA*     3.8    24.0    -      -       +      +
    230B  SER*     4.2     9.9    -      -       -      +
    233B  ALA*     3.9    33.7    -      -       +      +
    234B  ALA*     4.0    12.1    -      -       -      +
    237B  LEU*     4.4     4.7    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 199 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    195B  GLU*     2.9    34.0    +      -       -      +
    196B  VAL*     3.5    18.3    -      -       +      +
    198B  ILE*     1.3    78.6    -      -       -      +
    200B  ASP*     1.3    65.7    +      -       -      +
    202B  ARG*     3.2    10.0    +      -       -      +
    203B  ALA*     3.1    23.1    +      -       -      +
    230B  SER*     3.4    25.1    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASP 200 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196B  VAL*     2.7    39.1    +      -       -      +
    197B  MET*     3.2     7.3    +      -       -      +
    199B  GLU*     1.3    75.8    -      -       -      +
    201B  ALA*     1.3    61.3    +      -       -      +
    203B  ALA*     3.4     5.2    +      -       -      +
    204B  GLY      3.1     2.3    +      -       -      -
    205B  LEU*     2.8    44.7    +      -       +      +
    206B  LEU*     3.2    22.4    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 201 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    197B  MET      2.8    13.9    +      -       -      +
    198B  ILE*     3.0    11.0    +      -       -      +
    200B  ASP*     1.3    77.4    -      -       -      +
    202B  ARG*     1.3    57.6    +      -       -      +
    204B  GLY*     2.9    19.2    +      -       -      -
    206B  LEU*     4.2     5.6    -      -       +      +
    208B  THR*     3.7    29.5    -      -       +      +
    214B  LEU*     3.9    13.0    -      -       +      -
    218B  ALA*     4.0    15.5    -      -       +      -
    219B  PHE*     3.7    13.7    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 202 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    198B  ILE*     2.9    30.7    +      -       +      +
    199B  GLU*     3.7    10.3    -      -       -      +
    201B  ALA*     1.3    76.7    -      -       -      +
    203B  ALA*     1.3    59.8    +      -       -      +
    204B  GLY      3.1     0.9    +      -       -      -
    217B  MET      4.5     0.6    +      -       -      -
    218B  ALA*     3.0    31.8    +      -       +      +
    219B  PHE*     4.0    20.9    -      -       +      -
    227B  GLN*     3.5    29.3    +      -       -      +
    228B  LEU*     2.7    34.6    +      -       -      +
    229B  ASP*     4.7     0.4    -      -       -      +
    230B  SER*     3.6    24.7    +      -       -      +
    233B  ALA*     4.1    12.5    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 203 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    199B  GLU      3.1    15.1    +      -       -      +
    200B  ASP*     3.4     6.7    +      -       -      +
    201B  ALA      3.2     0.2    -      -       -      -
    202B  ARG*     1.3    75.8    -      -       -      +
    204B  GLY*     1.3    60.1    +      -       -      +
    205B  LEU*     3.1    29.7    +      -       +      +
----------------------------------------------------------
 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