Contacts of the helix formed by residues 263 - 286 (chain S) in PDB entry 1RZZ


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 GLU 263 (chain S).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    195R  LEU*     3.8    13.0    -      -       +      +
    198R  ALA*     4.7     2.7    -      -       +      -
    199R  ASN*     3.0    16.0    +      -       -      +
    238S  ILE*     3.6    30.6    -      -       +      +
    261S  THR*     3.1     4.7    +      -       -      +
    262S  MET*     1.3    77.5    -      -       -      +
    264S  GLY*     1.3    67.2    +      -       -      +
    265S  ILE      3.3     0.2    -      -       -      -
    266S  HIS*     3.1    20.9    +      -       -      +
    267S  ARG*     2.9    38.8    +      -       -      +
     34T  GLU*     5.5     0.4    -      -       -      -
     37T  ARG*     4.7     8.0    +      -       -      -
     62T  LYS*     3.2    15.1    +      -       -      +
     64T  PHE*     3.1    26.2    -      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLY 264 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    261S  THR*     2.8    12.4    +      -       -      -
    263S  GLU*     1.3    76.4    -      -       -      +
    265S  ILE*     1.3    64.9    +      -       -      +
    267S  ARG*     2.8    27.0    +      -       -      +
    268S  TRP*     3.0    14.0    +      -       -      -
     34T  GLU      5.2     2.2    -      -       -      -
     35T  ASN*     2.9    30.6    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 265 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    215S  LEU*     4.1    14.4    -      -       +      -
    219S  HIS*     3.5    32.8    -      -       +      +
    260S  ALA*     4.1     5.2    -      -       +      -
    261S  THR      2.9    14.8    +      -       -      +
    262S  MET      3.2    11.2    -      -       -      +
    264S  GLY*     1.3    74.5    -      -       -      +
    266S  HIS*     1.3    85.6    +      -       +      +
    268S  TRP*     3.1     9.7    +      -       +      +
    269S  ALA*     2.9    26.2    +      -       +      +
   2008S  U10      3.7    60.1    -      -       +      -
     35T  ASN*     3.4     1.8    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with HIS 266 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    190R  HIS*     3.4    14.1    -      +       -      -
    191R  GLY*     3.7    13.7    -      -       -      +
    194R  VAL*     3.4    32.6    -      -       +      +
    195R  LEU*     3.5    19.1    -      -       +      +
    219S  HIS*     3.4     3.1    +      +       -      -
    234S  GLU*     3.1    28.9    +      -       +      -
    262S  MET*     2.7    29.0    +      -       -      -
    263S  GLU      3.1     7.9    +      -       -      +
    264S  GLY      3.0     0.8    -      -       -      -
    265S  ILE*     1.3    88.8    -      -       +      +
    267S  ARG*     1.3    60.1    +      -       -      +
    269S  ALA*     3.6     6.3    -      -       +      -
    270S  ILE*     3.0    28.4    +      -       -      +
   2007S  FE2      2.2    25.3    -      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 267 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    195R  LEU*     3.9    21.7    -      -       +      +
    199R  ASN*     3.5    21.6    +      -       -      +
    145S  HIS*     4.9     6.3    +      -       -      -
    263S  GLU*     2.9    38.1    +      -       -      +
    264S  GLY*     2.8    15.0    +      -       -      +
    266S  HIS*     1.3    74.3    -      -       -      +
    268S  TRP*     1.3    67.8    +      -       -      +
    270S  ILE*     4.0     7.4    -      -       -      -
    271S  TRP*     3.1    35.7    +      -       +      +
     30T  TYR*     3.4    26.0    +      -       -      -
     31T  LEU*     3.6    16.2    -      -       +      -
     34T  GLU*     3.7    31.4    +      -       -      -
     62T  LYS*     4.0     6.3    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with TRP 268 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    215S  LEU*     3.7     8.5    -      -       +      +
    258S  PHE*     4.5     9.0    -      +       -      -
    259S  ASN      5.4     0.4    +      -       -      -
    260S  ALA*     4.2     2.2    -      -       +      -
    264S  GLY      3.0    15.4    +      -       -      -
    265S  ILE*     3.2    11.9    -      -       +      +
    267S  ARG*     1.3    79.3    -      -       -      +
    269S  ALA*     1.3    57.1    +      -       -      +
    271S  TRP*     4.0     1.4    -      -       -      +
    272S  MET*     3.0    32.3    +      -       +      +
   2008S  U10      3.6    58.9    -      -       +      +
     28T  ILE*     4.4    25.6    -      -       +      -
     31T  LEU*     3.3    42.8    -      -       +      +
     32T  GLN*     4.4    20.8    +      -       +      -
     35T  ASN*     3.0    36.9    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 269 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    187R  LEU*     3.6    38.7    -      -       +      +
    190R  HIS*     5.6     2.2    -      -       +      -
    191R  GLY*     4.5     4.5    -      -       -      +
    215S  LEU*     3.6    13.9    -      -       +      -
    219S  HIS*     5.8     4.0    -      -       +      -
    265S  ILE*     2.9    16.7    +      -       +      +
    266S  HIS*     3.7    12.1    -      -       +      +
    267S  ARG      3.1     0.2    -      -       -      -
    268S  TRP*     1.3    76.4    -      -       -      +
    270S  ILE*     1.3    65.8    +      -       -      +
    272S  MET*     3.2    10.9    +      -       -      +
    273S  ALA*     3.3    10.6    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 270 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    187R  LEU      4.6     0.7    -      -       -      -
    188R  ALA*     4.1    20.4    -      -       -      +
    191R  GLY*     4.5     0.6    -      -       -      -
    192R  ALA*     3.8    32.5    -      -       +      +
    195R  LEU*     4.0    11.9    -      -       +      -
    145S  HIS*     4.0    22.9    -      -       +      +
    148S  TRP*     6.1     0.9    -      -       +      -
    149S  ALA*     4.3     5.4    -      -       +      +
    266S  HIS      3.0    16.9    +      -       -      +
    267S  ARG*     3.4    15.3    -      -       +      +
    269S  ALA*     1.3    76.0    -      -       -      +
    271S  TRP*     1.3    77.9    +      -       +      +
    273S  ALA*     3.6     1.6    +      -       -      +
    274S  VAL*     3.0    45.3    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with TRP 271 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    267S  ARG*     3.1    27.6    +      -       -      +
    268S  TRP      4.2     2.0    -      -       -      +
    269S  ALA      3.2     0.4    -      -       -      -
    270S  ILE*     1.3    90.8    -      -       +      +
    272S  MET*     1.3    66.5    +      -       -      +
    274S  VAL*     4.4    14.6    -      -       +      -
    275S  LEU*     2.9    46.0    +      -       +      +
    278S  LEU*     5.0     5.4    -      -       +      -
     23T  PHE*     3.9    28.3    -      +       -      -
     27T  LEU*     3.6    38.0    -      -       +      +
     30T  TYR*     4.3    14.4    +      +       -      -
     31T  LEU*     4.1    18.8    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with MET 272 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    187R  LEU*     4.2     0.9    -      -       +      -
    207S  ALA      4.9     0.7    -      -       -      +
    208S  PHE*     3.5    48.6    -      -       +      +
    211S  GLY*     3.4    41.7    -      -       -      +
    212S  SER*     3.3    20.6    +      -       -      +
    214S  LEU*     5.7     0.9    -      -       +      -
    215S  LEU*     3.8    14.6    -      -       +      -
    268S  TRP*     3.0    23.0    +      -       +      +
    269S  ALA      3.2     5.5    +      -       -      +
    271S  TRP*     1.3    76.1    -      -       -      +
    273S  ALA*     1.3    61.1    +      -       -      +
    275S  LEU*     4.9     1.1    -      -       -      -
    276S  VAL*     3.5     1.4    +      -       -      +
   2004S  BCL      5.3     8.7    -      -       +      -
   2008S  U10      3.6    31.6    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 273 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    184R  ALA      3.3    27.6    -      -       -      +
    187R  LEU*     4.1     7.2    -      -       +      -
    188R  ALA*     3.7    22.7    -      -       +      +
    212S  SER*     3.6    10.1    +      -       -      +
    269S  ALA      3.3     9.2    +      -       -      +
    270S  ILE      4.1     0.2    -      -       -      +
    271S  TRP      3.2     0.2    -      -       -      -
    272S  MET*     1.3    76.9    -      -       -      +
    274S  VAL*     1.3    65.6    +      -       -      +
    275S  LEU      3.2     1.6    -      -       -      -
    276S  VAL*     3.0    24.7    +      -       -      +
   2005S  BPH      3.5    10.0    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 274 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188R  ALA*     4.8     2.0    -      -       +      -
    148S  TRP      5.5     0.7    -      -       -      +
    149S  ALA*     3.8    37.9    -      -       +      +
    152S  SER*     2.6    38.6    +      -       -      +
    270S  ILE*     3.0    31.8    +      -       +      +
    271S  TRP*     4.1    17.3    -      -       +      +
    273S  ALA*     1.3    75.5    -      -       -      +
    275S  LEU*     1.3    64.4    +      -       -      +
    276S  VAL      3.0     1.1    +      -       -      -
    277S  THR      3.3     1.9    +      -       -      -
    278S  LEU*     3.0    19.9    +      -       +      +
   2005S  BPH      3.7    10.5    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 275 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    208S  PHE*     3.5    46.7    -      -       +      -
    271S  TRP*     2.9    42.4    +      -       +      +
    272S  MET*     4.2     1.1    -      -       -      +
    274S  VAL*     1.3    75.8    -      -       -      +
    276S  VAL*     1.3    60.0    +      -       -      +
    278S  LEU*     3.7    27.1    -      -       +      -
    279S  THR*     2.8    31.2    +      -       -      +
     20T  PHE*     4.5    13.5    -      -       +      -
     23T  PHE*     4.3    12.8    -      -       +      -
     24T  LEU*     4.4     5.6    -      -       +      -
     27T  LEU*     3.7    21.5    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 276 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    184R  ALA*     4.6     7.9    -      -       +      -
    205S  SER*     2.9    33.6    +      -       -      +
    208S  PHE*     3.5    34.5    -      -       -      +
    209S  LEU*     3.8    15.3    -      -       +      +
    212S  SER*     3.8     5.4    -      -       -      +
    272S  MET      3.5     7.2    -      -       -      +
    273S  ALA*     3.0    18.8    +      -       -      +
    275S  LEU*     1.3    78.3    -      -       -      +
    277S  THR*     1.3    63.8    +      -       +      +
    279S  THR*     3.5     0.4    +      -       -      -
    280S  GLY*     3.2    14.2    +      -       -      -
   2003S  BCL      3.8    28.0    -      -       +      +
   2005S  BPH      5.2     6.1    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 277 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152S  SER*     2.6    41.9    +      -       -      -
    153S  ALA*     4.2     3.6    -      -       -      -
    155S  TRP*     3.2    10.2    -      -       -      -
    156S  LEU*     3.9    18.4    -      -       +      +
    274S  VAL      3.3     0.2    +      -       -      -
    276S  VAL*     1.3    79.7    -      -       +      +
    278S  LEU*     1.3    60.1    +      -       -      +
    280S  GLY*     3.7     1.6    -      -       -      +
    281S  GLY*     2.8    22.3    +      -       -      -
   2003S  BCL      3.7    34.3    -      -       +      +
   2005S  BPH      3.3    29.1    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 278 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152S  SER*     3.3    10.9    +      -       -      +
    155S  TRP*     3.3    36.0    +      -       +      +
    271S  TRP*     5.0     6.1    -      -       +      -
    274S  VAL*     3.0    25.5    +      -       +      +
    275S  LEU*     3.8    27.4    -      -       +      -
    277S  THR*     1.3    74.9    -      -       -      +
    279S  THR*     1.3    67.2    +      -       +      +
    282S  ILE*     3.3    24.5    -      -       +      +
     20T  PHE*     5.6     3.6    -      -       +      -
     23T  PHE*     5.0    10.1    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 279 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    201S  PHE*     3.4    28.8    -      -       +      +
    204S  LEU*     4.0     7.3    -      -       +      -
    205S  SER*     3.3    21.7    +      -       -      -
    208S  PHE*     4.0     9.4    -      -       +      -
    275S  LEU*     2.8    24.5    +      -       +      +
    278S  LEU*     1.3    74.6    -      -       +      +
    280S  GLY*     1.3    66.8    +      -       -      +
    282S  ILE*     3.3     5.5    +      -       +      +
    283S  GLY      3.0    18.7    +      -       -      -
     20T  PHE*     3.4    44.4    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLY 280 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    156S  LEU*     4.4     1.1    -      -       -      -
    205S  SER*     4.0     4.7    -      -       -      -
    276S  VAL      3.2    14.7    +      -       -      -
    277S  THR*     3.9     1.3    -      -       -      -
    278S  LEU      3.3     0.2    -      -       -      -
    279S  THR*     1.3    80.2    +      -       -      +
    281S  GLY*     1.3    63.8    +      -       -      +
    283S  GLY      3.3     0.3    +      -       -      -
    284S  ILE*     3.1    13.3    +      -       -      +
   2003S  BCL      3.0    48.9    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLY 281 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    155S  TRP*     3.2    25.6    -      -       -      -
    156S  LEU*     4.1    18.7    -      -       -      +
    159S  VAL*     3.8     7.3    -      -       -      +
    277S  THR      2.8    16.7    +      -       -      -
    279S  THR      3.3     0.2    -      -       -      -
    280S  GLY*     1.3    71.0    -      -       -      +
    282S  ILE*     1.3    58.6    +      -       -      +
    284S  ILE      3.3     1.0    +      -       -      -
    285S  LEU*     2.9    30.7    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 282 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    155S  TRP*     3.6    18.4    -      -       +      +
    201S  PHE*     3.7    39.3    -      -       +      -
    278S  LEU*     3.3    28.4    +      -       +      +
    279S  THR*     3.3     8.5    +      -       -      +
    280S  GLY      3.3     0.4    -      -       -      -
    281S  GLY*     1.3    75.6    -      -       -      +
    283S  GLY*     1.3    63.4    +      -       -      +
    285S  LEU*     3.3     5.4    +      -       +      +
    286S  LEU*     3.0    34.8    +      -       +      +
     16T  ALA*     4.7     6.5    -      -       +      -
     20T  PHE*     5.3     7.0    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with GLY 283 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    199S  ASN*     3.0    19.4    +      -       -      -
    201S  PHE*     3.5    25.1    -      -       -      +
    279S  THR      3.0    11.5    +      -       -      -
    280S  GLY      3.3     3.3    +      -       -      -
    281S  GLY      3.3     0.4    -      -       -      -
    282S  ILE*     1.3    76.9    -      -       -      +
    284S  ILE*     1.3    60.0    +      -       -      +
    286S  LEU*     3.8     2.1    +      -       -      -
    287S  SER*     2.8    25.1    +      -       -      -
    294S  TRP*     3.9     1.9    -      -       -      -
   2003S  BCL      4.5     3.4    -      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 284 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    156S  LEU*     4.5     4.7    -      -       +      -
    159S  VAL*     3.8    17.3    -      -       +      -
    160S  LEU*     4.0    17.3    -      -       +      -
    164S  ARG*     3.3    24.0    -      -       -      -
    189S  PHE*     3.7    29.6    -      -       +      -
    196S  LEU*     4.2     5.2    -      -       +      -
    280S  GLY      3.1    17.1    +      -       -      +
    281S  GLY*     3.8     3.8    -      -       -      +
    283S  GLY*     1.3    75.4    -      -       -      +
    285S  LEU*     1.3    64.7    +      -       -      +
    286S  LEU      3.1     1.8    -      -       -      -
    287S  SER*     3.0    15.8    +      -       -      -
   2003S  BCL      3.1    50.7    -      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 285 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    155S  TRP*     3.7    26.7    -      -       +      -
    159S  VAL*     3.7    11.6    -      -       +      +
    163S  ILE*     3.5    31.4    -      -       +      -
    164S  ARG*     4.1    15.7    -      -       -      +
    167S  LEU*     3.9    19.5    -      -       +      -
    281S  GLY      2.9    17.5    +      -       -      +
    282S  ILE*     3.3     6.3    +      -       +      +
    284S  ILE*     1.3    78.1    -      -       -      +
    286S  LEU*     1.3    56.6    +      -       +      +
    287S  SER      3.5     0.5    +      -       -      -
    289S  THR*     2.6    34.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 286 (chain S). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    201S  PHE*     4.0    16.8    -      -       +      -
    282S  ILE*     3.0    36.6    +      -       +      +
    283S  GLY*     4.1     0.7    -      -       -      +
    285S  LEU*     1.3    80.4    -      -       +      +
    287S  SER*     1.3    59.8    +      -       -      +
    289S  THR*     3.5     3.1    -      -       -      +
    290S  VAL*     3.1    25.1    +      -       +      -
    291S  VAL*     3.0    27.4    +      -       -      +
    294S  TRP*     4.1    16.8    -      -       +      -
     12T  LEU*     3.8    28.5    -      -       +      -
     13T  ALA*     3.8    26.7    -      -       +      -
     16T  ALA*     4.2     4.3    -      -       +      -
----------------------------------------------------------
 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