Contacts of the helix formed by residues 76 - 101 (chain B) in PDB entry 3QU3


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 PRO 76 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75B  LEU*     1.3    98.1    -      -       +      +
     77B  PRO*     1.3    66.9    -      -       +      +
     78B  PRO*     3.4     1.1    -      -       +      -
     79B  GLU*     3.0    35.3    +      -       +      +
     80B  ALA*     2.7    31.7    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with PRO 77 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75B  LEU      3.9     1.1    -      -       -      +
     76B  PRO*     1.3    84.8    -      -       +      +
     78B  PRO*     1.3    74.9    -      -       +      +
     80B  ALA*     3.3     5.6    +      -       +      +
     81B  GLU*     3.0    24.8    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with PRO 78 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76B  PRO*     4.2     1.3    -      -       +      -
     77B  PRO*     1.3   102.9    -      -       +      +
     79B  GLU*     1.3    72.2    +      -       -      +
     81B  GLU*     3.6     6.5    +      -       +      +
     82B  ALA*     3.2    26.2    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 79 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75B  LEU*     3.5    18.6    -      -       +      +
     76B  PRO*     3.0    46.4    +      -       +      +
     78B  PRO*     1.3    91.6    -      -       -      +
     80B  ALA*     1.3    62.8    +      -       -      +
     82B  ALA*     3.5     6.5    +      -       -      +
     83B  ALA*     3.2    17.3    +      -       -      +
     86B  ARG*     5.4     1.2    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 80 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73B  VAL*     3.4    34.5    -      -       +      +
     75B  LEU*     3.8     6.2    -      -       +      +
     76B  PRO      2.7    20.8    +      -       -      +
     77B  PRO*     3.8     5.4    -      -       +      +
     79B  GLU*     1.3    71.3    -      -       -      +
     81B  GLU*     1.3    65.3    +      -       -      +
     83B  ALA*     3.3     2.9    +      -       -      +
     84B  GLU*     3.2    32.3    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 81 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52B  GLU*     4.3     9.6    +      -       +      +
     77B  PRO      3.0    16.9    +      -       -      +
     78B  PRO*     3.7     8.1    -      -       +      +
     80B  ALA*     1.3    78.4    -      -       -      +
     82B  ALA*     1.3    56.9    +      -       -      +
     84B  GLU*     3.3     3.7    +      -       -      +
     85B  ARG*     3.0    55.3    +      -       -      -
     88B  ARG*     2.9    32.8    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 82 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78B  PRO      3.2    14.9    +      -       -      +
     79B  GLU*     3.8     8.1    -      -       -      +
     80B  ALA      3.3     0.2    -      -       -      -
     81B  GLU*     1.3    82.4    +      -       -      +
     83B  ALA*     1.3    61.3    +      -       -      +
     85B  ARG*     3.5     7.7    +      -       -      +
     86B  ARG*     3.2    44.1    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 83 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68B  TRP*     4.4     9.0    -      -       +      -
     73B  VAL*     4.4     8.7    -      -       +      -
     75B  LEU*     4.1    15.9    -      -       +      -
     79B  GLU      3.2    14.0    +      -       -      +
     80B  ALA*     3.5     9.2    -      -       -      +
     81B  GLU      3.2     0.4    -      -       -      -
     82B  ALA*     1.3    77.3    -      -       -      +
     84B  GLU*     1.3    59.6    -      -       -      +
     86B  ARG*     3.4    25.5    +      -       -      +
     87B  GLU*     3.0    24.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 84 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52B  GLU*     4.7     9.9    -      -       -      +
     59B  LYS*     4.2    18.7    +      -       -      +
     68B  TRP*     3.4    37.2    +      -       +      -
     72B  GLY*     4.4    10.2    -      -       -      -
     73B  VAL*     4.8     3.1    +      -       +      +
     80B  ALA*     3.2    16.8    +      -       -      +
     81B  GLU*     3.8     3.4    -      -       -      +
     83B  ALA*     1.3    72.0    -      -       -      +
     85B  ARG*     1.3    65.5    +      -       -      +
     86B  ARG      3.1     2.0    -      -       -      -
     87B  GLU*     2.9    19.6    +      -       -      +
     88B  ARG*     3.0    42.6    +      -       -      +
     91B  TRP*     4.1     7.7    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 85 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49B  ASP*     3.1    49.1    +      -       +      +
     50B  LEU      3.7    13.9    +      -       -      +
     51B  ASP*     2.8    31.1    +      -       -      +
     52B  GLU      5.1     0.2    -      -       -      +
     81B  GLU*     3.0    43.7    +      -       -      +
     82B  ALA*     3.6    10.3    -      -       -      +
     83B  ALA      3.3     0.2    -      -       -      -
     84B  GLU*     1.3    75.9    -      -       -      +
     86B  ARG*     1.3    62.3    +      -       +      +
     87B  GLU      3.2     0.9    +      -       -      -
     88B  ARG*     3.3    31.2    +      -       -      +
     89B  ARG*     4.6    12.3    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 86 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75B  LEU*     6.2     0.4    -      -       -      +
     79B  GLU      5.4     1.2    +      -       -      -
     82B  ALA*     3.2    32.5    +      -       -      +
     83B  ALA*     3.6    25.4    -      -       -      +
     84B  GLU      3.1     0.4    -      -       -      -
     85B  ARG*     1.3    77.3    -      -       +      +
     87B  GLU*     1.3    66.5    +      -       -      +
     88B  ARG      3.6     0.2    -      -       -      -
     89B  ARG*     5.1     5.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLU 87 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68B  TRP*     3.8    25.4    -      -       +      -
     83B  ALA      3.0    19.0    -      -       -      +
     84B  GLU*     2.9     8.8    +      -       -      +
     86B  ARG*     1.3    86.6    +      -       -      +
     88B  ARG*     1.3    60.3    -      -       -      +
     89B  ARG      3.4     1.8    -      -       -      -
     90B  GLY*     3.3     6.8    +      -       -      -
     91B  TRP*     3.1    49.3    +      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 88 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50B  LEU*     3.0    47.4    +      -       +      +
     51B  ASP      3.6    10.1    -      -       -      -
     52B  GLU*     3.7    30.7    +      -       -      +
     55B  ALA*     3.7    17.7    -      -       +      +
     58B  PHE*     4.5     1.2    -      -       -      -
     81B  GLU*     2.9    34.5    +      -       -      +
     84B  GLU*     3.0    47.5    +      -       -      +
     85B  ARG*     3.3    33.0    +      -       -      +
     87B  GLU*     1.3    73.6    -      -       -      +
     89B  ARG*     1.3    66.5    +      -       -      +
     91B  TRP*     3.5    16.3    -      -       +      +
     92B  LYS*     2.9    23.7    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 89 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46B  GLY      5.2     3.8    +      -       -      -
     47B  ARG*     3.2    25.3    +      -       -      +
     48B  ARG      3.6     7.8    +      -       -      -
     49B  ASP*     2.9    40.0    +      -       -      +
     50B  LEU*     3.7    18.3    -      -       +      +
     85B  ARG      4.6    15.0    +      -       -      -
     86B  ARG*     5.1     3.6    +      -       -      +
     87B  GLU      3.4     0.6    -      -       -      -
     88B  ARG*     1.3    76.3    -      -       -      +
     90B  GLY*     1.3    64.7    +      -       -      +
     92B  LYS*     3.2    19.1    +      -       -      +
     93B  THR*     3.0    26.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with GLY 90 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     86B  ARG      5.5     1.2    +      -       -      -
     87B  GLU      3.3     7.5    +      -       -      -
     89B  ARG*     1.3    78.5    -      -       -      +
     91B  TRP*     1.3    56.9    +      -       -      +
     93B  THR*     3.2     7.6    +      -       -      -
     94B  ASN*     2.8    32.2    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with TRP 91 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55B  ALA*     4.7     3.6    -      -       +      -
     58B  PHE*     3.7    19.9    -      -       +      +
     59B  LYS*     3.9    29.2    -      -       +      -
     61B  TRP*     5.1     0.3    -      -       -      -
     62B  ALA*     3.3    28.0    -      -       +      +
     65B  ARG*     4.5     6.5    +      -       -      +
     67B  ARG*     5.2     6.5    +      -       +      +
     68B  TRP*     3.4    54.9    -      +       +      +
     84B  GLU*     4.1    14.6    -      -       +      -
     87B  GLU*     3.1    35.9    +      -       +      +
     88B  ARG*     3.5    35.9    -      -       +      +
     90B  GLY*     1.3    76.5    -      -       -      +
     92B  LYS*     1.3    56.7    +      -       -      +
     94B  ASN*     3.5     5.3    +      -       -      +
     95B  PHE*     2.9    31.4    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with LYS 92 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45B  PHE*     3.7    35.0    -      -       +      -
     50B  LEU*     4.2     4.3    -      -       +      -
     58B  PHE*     3.6    25.1    -      -       +      -
     88B  ARG      2.9    13.0    +      -       -      +
     89B  ARG*     3.3    27.9    +      -       -      +
     91B  TRP*     1.3    77.3    -      -       -      +
     93B  THR*     1.3    82.1    +      -       -      +
     95B  PHE*     3.2     1.6    +      -       -      +
     96B  ARG*     2.8    63.7    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 93 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     89B  ARG      3.0    11.9    +      -       -      -
     90B  GLY*     3.6    10.8    -      -       -      -
     92B  LYS*     1.3    91.5    +      -       -      +
     94B  ASN*     1.3    69.4    +      -       -      +
     96B  ARG*     5.0     2.7    -      -       -      -
     97B  CYS*     3.1    39.0    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASN 94 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61B  TRP*     2.7    32.6    +      -       -      -
     65B  ARG*     2.9    37.7    -      -       -      +
     90B  GLY      2.8    21.6    +      -       -      +
     91B  TRP*     3.7     4.7    -      -       -      +
     93B  THR*     1.3    74.6    -      -       -      +
     95B  PHE*     1.3    62.6    +      -       -      +
     97B  CYS*     4.1     2.6    -      -       -      +
     98B  ALA*     3.1    23.2    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with PHE 95 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12B  PHE*     3.4    34.4    -      +       -      -
     15B  TRP*     4.2     1.6    -      +       -      -
     16B  LEU*     3.8    15.9    -      -       +      -
     40B  VAL*     4.2    15.3    -      -       +      -
     41B  PRO      5.6     0.4    -      -       -      -
     42B  TRP*     5.2     2.7    -      +       -      -
     57B  ILE*     3.7    41.7    -      -       +      -
     58B  PHE*     3.6    28.9    -      +       +      -
     61B  TRP*     3.9    16.8    -      -       +      +
     91B  TRP      2.9    19.4    +      -       -      +
     92B  LYS      3.5     3.1    -      -       -      +
     94B  ASN*     1.3    77.1    +      -       -      +
     96B  ARG*     1.3    71.3    +      -       +      +
     98B  ALA*     3.2     5.2    +      -       -      +
     99B  LEU*     3.1    40.1    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ARG 96 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41B  PRO      4.5     1.6    +      -       -      -
     42B  TRP*     3.7    52.2    -      -       +      +
     43B  LYS      2.8    41.8    +      -       -      +
     44B  HIS*     4.3     8.7    +      -       -      +
     45B  PHE*     3.7    10.5    -      -       -      +
     58B  PHE*     3.9    13.1    -      -       +      -
     92B  LYS*     2.8    51.8    +      -       +      +
     93B  THR*     4.3     3.1    -      -       -      +
     95B  PHE*     1.3    84.2    -      -       +      +
     97B  CYS*     1.3    60.4    +      -       -      +
     99B  LEU*     3.3     6.7    +      -       -      +
    100B  HIS*     2.8    40.0    +      -       +      +
----------------------------------------------------------
 Back to top of page

Residues in contact with CYS 97 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     93B  THR*     3.1    35.7    +      -       -      +
     94B  ASN*     4.1     3.1    -      -       -      +
     96B  ARG*     1.3    77.2    -      -       -      +
     98B  ALA*     1.3    60.0    +      -       -      +
    100B  HIS*     3.0    13.7    +      -       -      +
    101B  SER*     2.8    35.8    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 98 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12B  PHE*     3.5    31.0    -      -       +      +
     61B  TRP*     4.1    10.8    -      -       +      +
     94B  ASN*     3.1    18.8    +      -       -      +
     95B  PHE      3.5     5.2    -      -       -      +
     97B  CYS*     1.3    75.3    -      -       -      +
     99B  LEU*     1.3    52.5    +      -       -      +
    101B  SER*     3.6     6.2    +      -       -      +
    102B  THR*     2.7    32.7    +      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with LEU 99 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12B  PHE*     3.5    13.9    -      -       +      -
     16B  LEU*     3.8    25.6    -      -       +      -
     40B  VAL*     4.1    13.2    -      -       +      -
     42B  TRP*     4.1    14.8    -      -       +      -
     95B  PHE*     3.1    28.9    +      -       +      +
     96B  ARG*     3.5    10.5    -      -       -      +
     98B  ALA*     1.3    75.6    -      -       -      +
    100B  HIS*     1.3    64.2    +      -       -      +
    101B  SER      3.2     0.2    -      -       -      -
    102B  THR*     3.2    12.7    +      -       -      -
    105B  PHE*     4.2    11.6    -      -       +      -
    122B  TYR*     3.4    42.8    -      -       +      +
    135B   NA      2.9    20.7    -      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with HIS 100 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42B  TRP*     3.7    30.9    -      +       -      -
     96B  ARG*     2.8    32.6    +      -       +      +
     97B  CYS*     3.0    14.8    +      -       -      +
     99B  LEU*     1.3    77.4    -      -       -      +
    101B  SER*     1.3    61.1    +      -       -      +
    102B  THR      3.2     2.0    +      -       -      -
    103B  GLY*     4.9     1.4    +      -       -      -
    120B  LYS*     4.7     7.4    -      -       -      -
    122B  TYR*     4.6     8.7    +      -       -      -
    135B   NA      4.0     8.9    -      -       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with SER 101 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97B  CYS*     2.8    17.8    +      -       -      +
     98B  ALA*     3.9     5.6    -      -       -      -
     99B  LEU      3.2     0.2    -      -       -      -
    100B  HIS*     1.3    77.7    -      -       -      +
    102B  THR*     1.3    59.3    +      -       -      +
    103B  GLY*     3.5     4.9    +      -       -      -
----------------------------------------------------------
 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