Contacts of the helix formed by residues 323 - 328 (chain D) in PDB entry 2IBS


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 ARG 323 (chain D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    268D  PHE      4.0    11.1    +      -       -      -
    269D  ALA      4.3     2.2    +      -       -      -
    270D  ALA*     3.7    20.9    -      -       +      +
    274D  GLU*     2.9    40.6    +      -       -      -
    319D  ALA      3.7     1.8    +      -       -      -
    320D  LYS*     3.2    15.9    -      -       -      -
    322D  LEU*     1.3    92.1    +      -       -      +
    324D  ASP*     1.3    65.7    +      -       -      +
    325D  PHE*     3.6    37.0    -      -       +      -
    326D  TYR*     3.2    33.7    +      -       +      -
      1E    G      4.2    23.5    +      -       -      -
      2E    T      3.4    24.7    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with ASP 324 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    320D  LYS*     3.4    16.1    +      -       -      +
    323D  ARG*     1.3    72.8    -      -       -      +
    325D  PHE*     1.3    74.5    +      -       -      +
    326D  TYR      3.2     1.8    +      -       -      -
    327D  ALA*     3.3    21.1    +      -       -      +
    328D  THR*     4.6     0.9    +      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with PHE 325 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    267D  ARG*     3.7    26.7    -      -       +      -
    268D  PHE      3.8    17.3    -      -       -      -
    323D  ARG*     3.6    31.6    -      -       +      -
    324D  ASP*     1.3    88.9    -      -       -      +
    326D  TYR*     1.3    77.9    +      +       -      +
    327D  ALA      3.1     5.6    -      -       -      -
    328D  THR*     3.1    30.3    +      -       -      +
    330D  HIS*     3.2    13.4    +      -       -      -
    357D  HIS*     3.6    32.1    -      +       +      -
    359D  LEU*     3.7    35.9    -      -       +      -
----------------------------------------------------------
 Back to top of page

Residues in contact with TYR 326 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    269D  ALA*     3.4     6.6    -      -       -      +
    270D  ALA*     3.1    18.5    +      -       +      -
    275D  PHE*     4.5     5.2    -      +       -      -
    316D  LYS      5.5     0.5    -      -       -      +
    319D  ALA*     3.2    38.1    -      -       +      +
    320D  LYS*     4.9     1.6    -      -       -      -
    322D  LEU*     4.3     8.3    -      -       +      -
    323D  ARG*     3.4    36.3    -      -       +      +
    324D  ASP      3.2     1.2    -      -       -      -
    325D  PHE*     1.3    94.2    -      +       -      +
    327D  ALA*     1.3    56.3    +      -       -      +
    328D  THR      3.4     0.7    -      -       -      -
    330D  HIS*     4.5     6.1    -      +       -      -
    349D  ALA*     3.1    31.6    -      -       -      +
    350D  TYR      3.6    17.5    -      -       -      +
    351D  PRO*     4.4     5.2    -      -       +      -
    352D  TRP*     2.6    53.5    +      +       +      -
    357D  HIS*     4.1     3.6    -      +       -      -
----------------------------------------------------------
 Back to top of page

Residues in contact with ALA 327 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    320D  LYS*     3.8    30.1    -      -       +      +
    324D  ASP      3.3    14.3    +      -       -      +
    325D  PHE      3.1     0.6    -      -       -      -
    326D  TYR*     1.3    80.2    -      -       -      +
    328D  THR*     1.3    65.3    +      -       +      +
    329D  PRO*     4.4     1.9    -      -       -      +
    349D  ALA*     3.9     7.6    -      -       -      +
----------------------------------------------------------
 Back to top of page

Residues in contact with THR 328 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    324D  ASP      4.6     0.8    +      -       -      +
    325D  PHE*     3.1    17.7    +      -       -      +
    327D  ALA*     1.3    87.3    -      -       +      +
    329D  PRO*     1.3    67.6    +      -       +      +
    330D  HIS*     2.8    31.5    +      -       -      +
    349D  ALA*     3.9     6.6    -      -       -      +
    359D  LEU*     5.3     4.7    -      -       -      +
----------------------------------------------------------
 Back to top of page


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


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

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

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