Contacts of the helix formed by residues 266 - 274 (chain C) in PDB entry 1IXR


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 266 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    265C  VAL*     1.3    81.2    -      -       -      +
    267C  LEU*     1.3    56.4    +      -       -      -
    268C  ALA*     2.4    23.0    +      -       -      -
    269C  THR      3.0    13.9    +      -       -      -
    270C  LEU*     3.5     9.2    +      -       -      -
    300C  ARG      4.9     0.2    -      -       -      -
    301C  GLY*     3.7    13.9    -      -       -      -
    302C  ARG*     3.4    11.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 267 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    266C  GLY*     1.3    68.7    -      -       -      -
    268C  ALA*     1.3    68.4    +      -       -      +
    270C  LEU*     4.8     2.7    -      -       -      -
    271C  ALA*     2.8    27.7    +      -       -      +
    278C  PRO*     2.9    38.6    -      -       +      +
    281C  LEU*     3.5    13.7    -      -       +      -
    282C  GLU*     3.2    36.8    -      -       +      +
    286C  GLU*     3.6     7.0    -      -       -      +
    302C  ARG*     2.8    41.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 268 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    265C  VAL      5.4     1.1    -      -       -      +
    266C  GLY*     2.4    13.9    +      -       -      +
    267C  LEU*     1.3    80.3    -      -       -      +
    269C  THR*     1.3    67.7    +      -       -      +
    271C  ALA*     3.7     2.6    +      -       -      +
    272C  THR*     3.7    12.3    +      -       -      -
    278C  PRO*     5.4     2.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 269 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    259C  ARG*     5.1     5.8    -      -       -      +
    260C  PHE*     3.7    26.0    -      -       +      -
    265C  VAL*     3.8    14.6    +      -       -      +
    266C  GLY      3.0     4.0    +      -       -      -
    268C  ALA*     1.3    79.2    -      -       -      +
    270C  LEU*     1.3    55.0    +      -       -      +
    272C  THR*     2.5    38.3    +      -       +      -
    273C  ALA*     3.1    13.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 270 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    252C  ILE*     4.8     6.5    -      -       +      +
    255C  VAL*     5.3     4.3    -      -       +      -
    256C  LEU*     3.7    33.7    -      -       +      +
    260C  PHE*     4.2    11.4    -      -       +      -
    265C  VAL*     3.6    17.6    -      -       +      +
    266C  GLY      3.5     9.4    +      -       -      +
    267C  LEU*     4.4     0.9    -      -       -      +
    269C  THR*     1.3    78.8    -      -       -      +
    271C  ALA*     1.3    55.0    +      -       -      +
    272C  THR      2.9     0.2    +      -       -      -
    273C  ALA*     3.0     8.0    +      -       -      -
    274C  LEU*     2.7    67.4    +      -       +      +
    281C  LEU*     3.8    13.9    -      -       +      -
    286C  GLU*     5.1     0.4    -      -       -      +
    295C  LEU*     6.0     2.2    -      -       +      -
    302C  ARG*     4.2    22.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 271 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    267C  LEU*     2.8    24.7    +      -       +      +
    268C  ALA      4.0     1.8    -      -       -      +
    269C  THR      2.9     0.2    +      -       -      -
    270C  LEU*     1.3    74.1    -      -       -      +
    272C  THR*     1.3    50.9    +      -       -      +
    274C  LEU*     4.4     1.3    -      -       -      -
    275C  SER      3.3     2.3    +      -       -      -
    276C  GLU*     2.5    43.3    +      -       -      +
    277C  ASP      4.5     0.2    -      -       -      -
    278C  PRO*     3.3    40.6    -      -       +      -
    281C  LEU*     3.8    18.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 272 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    268C  ALA      3.7     8.5    +      -       -      -
    269C  THR*     2.5    19.3    +      -       +      -
    271C  ALA*     1.3    70.2    -      -       -      +
    273C  ALA*     1.3    55.7    +      -       -      +
    274C  LEU      2.9     4.9    -      -       -      -
    275C  SER*     2.5    29.1    +      -       -      +
    276C  GLU      4.4     3.1    +      -       -      +
    278C  PRO*     6.1     0.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 273 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    255C  VAL*     4.2    13.1    -      -       +      +
    259C  ARG*     3.2    33.2    +      -       -      +
    260C  PHE*     3.4    29.2    -      -       +      -
    269C  THR*     3.1    10.9    +      -       +      +
    270C  LEU      3.0     5.5    +      -       -      +
    272C  THR*     1.3    77.1    -      -       -      +
    274C  LEU*     1.3    57.4    +      -       -      +
    275C  SER*     3.2     1.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 274 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    248C  ARG*     2.4    59.7    +      -       -      +
    251C  GLU*     4.6     1.1    -      -       +      -
    252C  ILE*     3.5    51.1    -      -       +      +
    255C  VAL*     4.1    15.5    -      -       +      -
    270C  LEU*     2.7    38.7    +      -       +      +
    271C  ALA      3.8     5.6    -      -       -      +
    273C  ALA*     1.3    76.9    -      -       -      +
    275C  SER*     1.3    67.0    +      -       -      +
    276C  GLU*     4.2     3.6    -      -       +      -
    281C  LEU*     3.7    16.8    -      -       +      -
----------------------------------------------------------
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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