Contacts of the helix formed by residues 266 - 272 (chain C) in PDB entry 2X1L


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 ILE 266 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10C  ALA*     3.8    13.9    -      -       +      -
    230C  TRP*     3.6    21.8    -      -       +      -
    262C  ILE*     4.0     6.1    -      -       +      -
    263C  GLY      3.5    13.0    -      -       -      +
    264C  LYS      3.2     0.2    -      -       -      -
    265C  ASP*     1.3    95.8    -      -       -      +
    267C  ILE*     1.3    64.1    +      -       -      +
    268C  ARG      3.4     2.5    -      -       -      -
    269C  PHE*     3.5    17.9    +      -       +      +
    270C  HIS*     3.1    40.6    +      -       +      -
    600C  MET*     3.5    29.6    -      -       +      +
    601C  ADN      3.4    23.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 267 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    186C  ILE*     3.8    22.9    -      -       +      -
    187C  GLY      4.9     1.3    -      -       -      +
    191C  ARG*     3.3    37.2    -      -       +      -
    194C  GLU*     5.8     1.8    -      -       -      +
    195C  ILE*     3.9    17.0    -      -       +      -
    262C  ILE*     3.6    13.9    -      -       +      -
    263C  GLY      4.0     1.2    +      -       -      -
    264C  LYS      3.3    19.9    +      -       -      +
    265C  ASP      3.6     1.0    -      -       -      -
    266C  ILE*     1.3    77.1    -      -       -      +
    268C  ARG*     1.3    62.3    +      -       +      +
    270C  HIS*     3.1     2.6    +      -       -      -
    271C  THR*     2.7    52.0    +      -       +      +
    289C  ILE*     5.1     2.2    -      -       +      -
    291C  ALA*     3.9    15.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 268 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    194C  GLU      5.5     1.2    +      -       -      -
    195C  ILE*     3.8    17.7    -      -       +      +
    198C  PHE*     3.5    60.6    -      -       +      +
    265C  ASP      5.6     0.2    +      -       -      -
    266C  ILE      3.4     0.6    -      -       -      -
    267C  ILE*     1.3    81.1    -      -       +      +
    269C  PHE*     1.3    63.6    +      -       +      +
    271C  THR*     3.9     5.8    -      -       -      -
    272C  VAL*     3.0    35.6    +      -       +      +
    273C  TYR*     3.3    16.6    +      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 269 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    228C  TYR*     4.2     9.2    -      +       -      -
    230C  TRP*     3.4    76.7    -      +       +      -
    234C  LEU*     3.5     8.4    -      -       +      +
    265C  ASP      4.4     5.2    -      -       -      -
    266C  ILE*     3.7    28.3    -      -       +      +
    267C  ILE      3.2     0.6    -      -       -      -
    268C  ARG*     1.3    82.1    -      -       +      +
    270C  HIS*     1.3    58.9    +      -       -      +
    273C  TYR*     3.6    33.1    -      +       +      +
    274C  TRP*     3.0    27.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 270 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230C  TRP*     3.8    11.2    -      +       -      -
    234C  LEU*     3.6    13.8    -      -       +      +
    237C  TYR*     2.8    37.4    +      +       -      -
    260C  HIS*     4.7     9.4    -      +       +      -
    262C  ILE*     3.5    36.1    -      -       +      +
    266C  ILE*     3.1    29.4    +      -       +      -
    267C  ILE      3.1     6.7    +      -       -      +
    269C  PHE*     1.3    77.7    -      -       -      +
    271C  THR*     1.3    60.8    +      -       -      +
    272C  VAL      3.7     0.4    -      -       -      -
    274C  TRP*     3.4    19.1    -      +       +      +
    275C  PRO*     3.4    13.2    -      -       -      +
    289C  ILE*     4.0    20.7    -      -       +      +
    600C  MET*     3.6    19.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 271 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    179C  TYR*     2.7    27.5    +      -       -      -
    185C  PHE*     3.9     6.2    -      -       +      -
    186C  ILE*     3.7    34.3    -      -       +      -
    195C  ILE*     3.4    23.6    -      -       -      +
    267C  ILE*     2.7    37.2    +      -       +      +
    268C  ARG*     3.9     0.3    -      -       -      -
    270C  HIS*     1.3    79.7    -      -       -      +
    272C  VAL*     1.3    57.5    +      -       -      +
    275C  PRO*     3.3    16.1    -      -       -      +
    289C  ILE*     3.9    22.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 272 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168C  LEU*     4.2     2.7    -      -       +      -
    175C  LEU*     3.7     8.8    -      -       +      +
    179C  TYR*     3.7    13.0    -      -       -      +
    195C  ILE*     3.9    11.9    -      -       +      -
    198C  PHE*     4.3    13.2    -      -       +      -
    199C  VAL*     3.8    13.7    -      -       +      -
    203C  LEU*     3.9    36.3    -      -       +      -
    268C  ARG*     3.0    18.1    +      -       +      +
    271C  THR*     1.3    84.1    -      -       -      +
    273C  TYR*     1.3    81.2    +      -       +      +
    274C  TRP      3.5     1.1    -      -       -      -
    275C  PRO*     3.5     3.3    -      -       -      +
    276C  ALA*     3.4    22.5    +      -       -      +
----------------------------------------------------------
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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