Contacts of the helix formed by residues 547 - 578 (chain N) in PDB entry 1AIK


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 547 (chain N).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    652C  GLN*     3.5    12.2    -      -       -      +
    656C  ASN*     3.0    34.1    +      -       -      -
    659C  GLU*     4.9     7.9    +      -       -      -
    545N  ACE      3.3     0.6    -      -       -      -
    546N  SER*     1.3    81.7    +      -       -      +
    548N  ILE*     1.3    52.0    +      -       -      +
    550N  GLN*     3.3     6.9    -      -       -      +
    551N  GLN      2.7    27.4    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 548 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    656C  ASN*     4.6    10.5    -      -       +      +
    660C  LEU*     5.4    12.6    -      -       +      -
    545N  ACE      3.3    23.1    -      -       +      +
    547N  GLY*     1.3    75.1    -      -       -      +
    549N  VAL*     1.3    61.6    +      -       +      +
    551N  GLN*     3.3     7.6    +      -       +      +
    552N  GLN*     2.9    46.8    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 549 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    545N  ACE      3.0    16.3    +      -       -      +
    546N  SER*     3.5     9.9    -      -       -      +
    548N  ILE*     1.3    77.3    -      -       +      +
    550N  GLN*     1.3    61.8    +      -       -      +
    552N  GLN*     3.5    15.7    +      -       -      +
    553N  ASN*     3.2    21.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 550 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    648C  GLU*     4.2     9.1    +      -       -      +
    652C  GLN*     3.5    17.9    +      -       -      +
    546N  SER*     2.8    22.1    +      -       -      +
    547N  GLY*     3.3    11.4    -      -       -      +
    549N  VAL*     1.3    72.7    -      -       -      +
    551N  GLN*     1.3    57.5    +      -       -      +
    553N  ASN*     3.1    19.2    +      -       -      +
    554N  ASN*     2.8    54.8    +      -       -      +
    557N  ARG*     5.2     2.7    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 551 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    649C  SER*     3.1    50.3    +      -       -      +
    652C  GLN*     3.9     8.3    -      -       +      +
    653C  GLN*     2.8    32.4    +      -       -      +
    656C  ASN*     3.6    10.1    -      -       -      +
    547N  GLY      2.7    22.0    +      -       -      +
    548N  ILE*     3.6     7.6    -      -       -      +
    550N  GLN*     1.3    70.5    -      -       -      +
    552N  GLN*     1.3    52.8    +      -       +      +
    554N  ASN*     3.0    10.6    +      -       -      +
    555N  LEU*     2.8    54.2    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 552 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    548N  ILE*     2.9    32.6    +      -       +      +
    549N  VAL*     3.5    18.8    -      -       +      +
    551N  GLN*     1.3    72.7    -      -       +      +
    553N  ASN*     1.3    61.1    +      -       -      +
    555N  LEU*     3.4    14.3    +      -       +      +
    556N  LEU*     2.9    30.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASN 553 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    549N  VAL      3.2     9.6    +      -       -      +
    550N  GLN*     3.1    21.2    +      -       -      +
    552N  GLN*     1.3    77.5    -      -       -      +
    554N  ASN*     1.3    60.0    +      -       -      +
    556N  LEU*     3.4    10.7    +      -       -      +
    557N  ARG*     3.0    55.6    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASN 554 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    645C  LEU*     4.2     8.5    -      -       +      +
    648C  GLU*     3.2    22.2    +      -       -      +
    649C  SER*     3.2    24.2    +      -       -      +
    652C  GLN*     4.1    10.3    +      -       -      +
    550N  GLN*     2.8    40.8    +      -       -      +
    551N  GLN*     3.0    14.3    +      -       -      +
    553N  ASN*     1.3    78.3    -      -       -      +
    555N  LEU*     1.3    61.4    +      -       -      +
    557N  ARG*     2.8    37.5    +      -       -      +
    558N  ALA*     3.1    21.5    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 555 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    649C  SER*     4.1    18.2    -      -       -      +
    551N  GLN*     2.8    40.3    +      -       +      +
    552N  GLN*     3.7    16.8    -      -       +      +
    553N  ASN      3.3     0.2    -      -       -      -
    554N  ASN*     1.3    69.9    -      -       -      +
    556N  LEU*     1.3    58.7    +      -       -      +
    558N  ALA*     2.9    24.2    +      -       +      +
    559N  ILE*     2.9    26.1    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 556 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    552N  GLN      2.9    18.3    +      -       -      +
    553N  ASN*     3.8    11.9    -      -       -      +
    555N  LEU*     1.3    73.0    -      -       -      +
    557N  ARG*     1.3    64.8    +      -       +      +
    559N  ILE*     3.3    18.8    +      -       +      +
    560N  GLU*     3.0    50.2    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 557 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    641C  LEU*     5.6     1.1    -      -       -      +
    645C  LEU*     3.4    40.0    -      -       +      +
    648C  GLU*     3.6    14.8    +      -       -      -
    550N  GLN*     5.2     3.8    +      -       -      +
    553N  ASN*     3.0    45.0    +      -       -      +
    554N  ASN*     2.8    28.9    +      -       -      +
    556N  LEU*     1.3    77.1    -      -       +      +
    558N  ALA*     1.3    57.3    +      -       -      +
    560N  GLU*     3.2    16.8    +      -       -      +
    561N  ALA*     2.9    29.8    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 558 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    642C  ILE*     4.4     4.7    -      -       +      +
    645C  LEU*     3.5    21.3    -      -       +      +
    646C  ILE*     5.2    12.3    -      -       +      -
    649C  SER*     5.5     1.6    -      -       -      +
    554N  ASN      3.1    13.7    +      -       -      +
    555N  LEU*     2.9    17.6    +      -       +      +
    557N  ARG*     1.3    76.5    -      -       -      +
    559N  ILE*     1.3    55.5    +      -       +      +
    561N  ALA*     3.3     4.7    +      -       -      +
    562N  GLN*     2.9    38.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 559 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    555N  LEU*     2.9    27.1    +      -       +      +
    556N  LEU*     3.6    18.6    -      -       +      +
    558N  ALA*     1.3    74.9    -      -       +      +
    560N  GLU*     1.3    62.2    +      -       +      +
    562N  GLN*     3.2    15.2    +      -       +      +
    563N  GLN*     2.8    30.3    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 560 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    556N  LEU*     3.0    49.4    +      -       +      +
    557N  ARG*     3.6    13.8    -      -       -      +
    559N  ILE*     1.3    77.7    -      -       +      +
    561N  ALA*     1.3    63.1    +      -       -      +
    563N  GLN*     3.1     9.8    +      -       -      +
    564N  HIS*     3.1    33.4    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 561 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    638C  TYR*     4.3     8.7    -      -       +      +
    641C  LEU*     4.3    22.7    -      -       +      -
    642C  ILE*     3.3    33.3    -      -       +      +
    645C  LEU*     4.6     1.3    -      -       +      -
    557N  ARG      2.9    17.0    +      -       -      +
    558N  ALA*     3.5     5.2    -      -       -      +
    559N  ILE      3.2     0.2    -      -       -      -
    560N  GLU*     1.3    75.1    -      -       -      +
    562N  GLN*     1.3    64.1    +      -       -      +
    564N  HIS*     3.1    21.2    +      -       -      +
    565N  LEU*     3.2     9.7    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 562 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    642C  ILE*     3.6    32.5    -      -       +      +
    646C  ILE*     5.1     4.9    -      -       -      +
    558N  ALA*     2.9    25.3    +      -       -      +
    559N  ILE*     3.2    15.0    +      -       -      +
    561N  ALA*     1.3    75.1    -      -       -      +
    563N  GLN*     1.3    55.4    +      -       -      +
    565N  LEU*     3.2     7.3    +      -       +      +
    566N  LEU*     2.8    42.0    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 563 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    559N  ILE*     2.8    15.9    +      -       +      +
    560N  GLU*     3.3    13.2    -      -       -      +
    562N  GLN*     1.3    78.0    -      -       -      +
    564N  HIS*     1.3    66.4    +      -       +      +
    566N  LEU*     3.1    28.1    +      -       -      +
    567N  GLN*     3.0    53.6    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with HIS 564 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    638C  TYR*     2.9    52.7    +      +       +      -
    560N  GLU*     3.1    20.3    +      -       +      +
    561N  ALA*     3.1    10.2    +      -       -      +
    563N  GLN*     1.3    80.6    -      -       +      +
    565N  LEU*     1.3    60.9    +      -       -      +
    567N  GLN*     3.2    11.6    +      -       +      +
    568N  LEU*     2.9    31.1    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 565 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    635C  ILE*     3.7    38.6    -      -       +      +
    638C  TYR*     3.7    20.8    -      -       +      +
    639C  THR*     3.9    11.2    -      -       +      +
    642C  ILE*     3.7    29.4    -      -       +      -
    561N  ALA      3.2     4.3    +      -       -      +
    562N  GLN*     3.3    11.4    -      -       +      +
    564N  HIS*     1.3    78.8    -      -       -      +
    566N  LEU*     1.3    61.8    +      -       -      +
    568N  LEU*     3.1     6.1    +      -       +      +
    569N  THR*     3.0    32.8    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 566 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    562N  GLN*     2.8    24.2    +      -       +      +
    563N  GLN*     3.1    36.8    +      -       -      +
    565N  LEU*     1.3    69.9    -      -       -      +
    567N  GLN*     1.3    62.5    +      -       -      +
    569N  THR*     2.6    25.7    +      -       -      +
    570N  VAL*     3.1    20.1    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 567 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    563N  GLN*     3.0    44.6    +      -       +      +
    564N  HIS*     3.2    13.4    +      -       +      +
    566N  LEU*     1.3    72.1    -      -       -      +
    568N  LEU*     1.3    65.2    +      -       +      +
    570N  VAL*     3.2    14.6    +      -       -      +
    571N  TRP*     2.9    28.8    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 568 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    631C  TRP*     2.8    29.6    +      -       +      +
    634C  GLU*     3.7    50.0    -      -       +      +
    635C  ILE*     3.3    33.7    -      -       +      -
    638C  TYR*     3.7    13.2    -      -       +      -
    564N  HIS*     2.9    23.0    +      -       +      +
    565N  LEU*     3.1     5.3    +      -       -      +
    567N  GLN*     1.3    81.2    -      -       +      +
    569N  THR*     1.3    57.9    +      -       -      +
    571N  TRP*     3.2     7.8    +      -       +      +
    572N  GLY      2.9    17.0    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 569 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    631C  TRP*     4.5    11.0    -      -       +      +
    635C  ILE*     5.0     8.1    -      -       +      -
    565N  LEU*     3.0    22.2    +      -       +      +
    566N  LEU*     2.6    29.6    +      -       -      +
    568N  LEU*     1.3    77.0    -      -       -      +
    570N  VAL*     1.3    56.8    +      -       -      +
    572N  GLY*     3.0     2.8    +      -       -      +
    573N  ILE*     2.9    39.4    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with VAL 570 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    566N  LEU*     3.1    22.0    +      -       +      +
    567N  GLN*     3.2    17.0    +      -       -      +
    569N  THR*     1.3    72.8    -      -       -      +
    571N  TRP*     1.3    67.3    +      -       -      +
    573N  ILE*     3.2    14.8    +      -       +      +
    574N  LYS*     2.9    53.9    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with TRP 571 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    627C  ACE      4.0    26.5    -      -       +      -
    628C  TRP*     3.6    40.8    -      +       -      -
    631C  TRP*     3.3    36.8    -      +       +      -
    567N  GLN      2.9    13.5    +      -       -      +
    568N  LEU*     3.3    13.5    -      -       +      +
    570N  VAL*     1.3    77.3    -      -       -      +
    572N  GLY*     1.3    63.0    +      -       -      +
    574N  LYS*     4.0     7.3    -      -       +      +
    575N  GLN*     3.0    63.7    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLY 572 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    628C  TRP*     3.6    24.0    -      -       -      -
    631C  TRP*     4.3     7.0    -      -       -      -
    568N  LEU      2.9    13.3    +      -       -      -
    569N  THR      3.0     4.6    +      -       -      -
    571N  TRP*     1.3    80.8    -      -       -      +
    573N  ILE*     1.3    63.2    +      -       -      +
    575N  GLN*     3.4     2.1    +      -       -      +
    576N  LEU*     3.0    31.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ILE 573 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    569N  THR*     2.9    29.3    +      -       -      +
    570N  VAL*     3.6    14.8    -      -       +      +
    572N  GLY*     1.3    75.7    -      -       -      +
    574N  LYS*     1.3    61.2    +      -       +      +
    576N  LEU*     3.2     7.9    +      -       -      +
    577N  GLN*     2.8    31.4    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 574 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    570N  VAL*     2.9    46.1    +      -       +      +
    571N  TRP*     4.0     6.5    -      -       +      +
    573N  ILE*     1.3    73.8    -      -       +      +
    575N  GLN*     1.3    59.2    +      -       -      +
    577N  GLN*     3.7    10.2    -      -       -      +
    578N  ALA*     2.9    30.5    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 575 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    628C  TRP*     3.8    13.6    +      -       +      +
    571N  TRP*     3.0    67.7    +      -       +      +
    572N  GLY      3.4     7.9    -      -       -      +
    574N  LYS*     1.3    80.0    -      -       -      +
    576N  LEU*     1.3    63.9    +      -       -      +
    578N  ALA*     3.4    11.5    +      -       -      +
    579N  ARG*     3.6    44.3    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 576 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    628C  TRP*     3.9    25.6    -      -       +      +
    572N  GLY      3.0    20.4    +      -       -      +
    573N  ILE*     3.9     5.8    -      -       -      +
    575N  GLN*     1.3    81.2    -      -       -      +
    577N  GLN*     1.3    61.7    +      -       -      +
    579N  ARG*     3.3    17.4    +      -       -      +
    580N  ILE*     3.1    36.6    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLN 577 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    573N  ILE*     2.8    24.8    +      -       +      +
    574N  LYS*     3.7     9.9    -      -       -      +
    575N  GLN      3.3     0.2    -      -       -      -
    576N  LEU*     1.3    74.1    -      -       -      +
    578N  ALA*     1.3    69.9    +      -       -      +
    580N  ILE*     4.5     5.6    -      -       -      +
    581N  LEU*     3.0    58.6    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 578 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    574N  LYS      2.9    17.6    +      -       -      +
    575N  GLN*     3.7     8.5    -      -       -      +
    576N  LEU      3.3     0.4    -      -       -      -
    577N  GLN*     1.3    83.4    +      -       -      +
    579N  ARG*     1.3    63.4    +      -       +      +
    581N  LEU      3.7    13.8    -      -       -      +
----------------------------------------------------------
 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