Contacts of the helix formed by residues 238 - 240 (chain A) in PDB entry 1XGS


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 238 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  LEU*     3.5    28.3    -      -       -      +
     34A  ALA*     3.8    14.7    -      -       -      +
     35A  GLU*     3.0    26.2    +      -       -      +
     38A  GLU*     2.9    42.8    +      -       -      -
     51A  PRO*     4.1     3.2    -      -       -      +
     64A  THR*     2.9    24.2    +      -       -      -
     65A  PRO*     2.8    33.0    +      -       -      +
     66A  TYR*     3.9     5.8    -      -       -      +
     67A  LYS*     4.4     9.8    -      -       +      +
    204A  LEU      4.8     0.2    +      -       -      -
    236A  ALA*     3.8     5.5    -      -       +      +
    237A  TYR*     1.3    80.2    -      -       -      +
    239A  TRP*     1.3    73.3    +      -       +      +
    240A  LEU      3.0     1.2    +      -       -      -
    241A  GLN*     3.2    32.3    +      -       -      +
    242A  ASN*     4.3     6.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 239 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35A  GLU*     5.4     0.4    -      -       -      -
     38A  GLU*     3.0    25.1    +      -       -      -
     48A  PRO*     4.0    32.3    -      -       +      -
     50A  PHE*     4.2     1.3    -      -       -      -
     51A  PRO*     3.7    33.0    -      -       +      -
    225A  LYS*     5.3     1.6    -      -       -      -
    230A  TYR*     3.4    52.3    +      +       +      +
    234A  PRO      3.9     7.6    -      -       -      -
    235A  PHE*     3.6    26.2    -      -       +      -
    236A  ALA*     3.2    23.0    +      -       +      +
    237A  TYR      3.1     0.2    +      -       -      -
    238A  ARG*     1.3    93.5    -      -       +      +
    240A  LEU*     1.3    60.6    +      -       +      +
    242A  ASN*     4.5     8.3    +      -       -      +
    243A  ASP*     4.6     4.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 240 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  LEU*     4.0    18.2    -      -       +      -
    225A  LYS*     3.9    12.3    -      -       +      -
    226A  ILE*     4.9     3.6    -      -       +      -
    230A  TYR*     3.8    27.4    -      -       +      +
    235A  PHE*     3.9    30.5    -      -       +      -
    236A  ALA      4.3     7.2    -      -       -      +
    237A  TYR*     2.9    12.4    +      -       -      +
    239A  TRP*     1.3    77.4    -      -       -      +
    241A  GLN*     1.3    58.3    +      -       -      +
    242A  ASN      2.9    12.4    +      -       -      -
    243A  ASP*     3.2    35.6    +      -       +      +
    244A  MET      4.0     2.3    +      -       -      -
    249A  LEU*     3.6    32.3    -      -       +      +
    253A  LEU*     4.5     8.7    -      -       +      -
----------------------------------------------------------
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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