Contacts of the helix formed by residues 246 - 250 (chain A) in PDB entry 1XRB


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 246 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    243A  GLY*     3.3    25.1    -      -       -      +
    244A  ARG      3.3     3.1    +      -       -      +
    245A  LYS*     1.3    75.7    -      -       -      +
    247A  ILE*     1.3    70.6    +      -       +      +
    249A  ASP*     3.6     8.9    -      -       +      +
    250A  THR*     3.2    20.8    +      -       -      -
    257A  HIS*     3.2    37.6    -      -       +      +
    259A  GLY      3.1    24.7    -      -       -      +
    260A  GLY      3.7    21.3    -      -       -      +
    261A  ALA*     3.8    12.1    -      -       +      +
    414A    K      3.3    13.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 247 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    244A  ARG      5.2     0.2    +      -       -      -
    245A  LYS*     3.4     0.8    -      -       -      +
    246A  ILE*     1.3    80.3    -      -       +      +
    248A  VAL*     1.3    67.0    +      -       +      +
    250A  THR*     3.1    18.6    +      -       -      +
    252A  GLY*     3.2    23.6    +      -       -      -
    253A  GLY*     3.2    37.7    -      -       -      +
    255A  ALA      5.1     4.3    -      -       -      +
    257A  HIS*     4.0    31.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 248 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8A  GLU*     4.2    26.2    -      -       +      +
      9A  SER*     4.1    14.1    -      -       -      +
     10A  VAL*     4.5     8.3    -      -       +      +
     17A  LYS*     4.2    20.2    -      -       +      -
    138A  ILE*     3.7     9.9    -      -       -      +
    142A  HIS*     3.2    40.6    +      -       +      +
    245A  LYS*     3.6    37.9    -      -       +      +
    247A  ILE*     1.3    78.5    -      -       +      +
    249A  ASP*     1.3    66.2    -      -       -      +
    250A  THR      3.9     1.0    -      -       -      +
    357A  TYR      5.8     1.1    -      -       -      +
    358A  GLY      5.6     1.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 249 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  LYS*     2.8    37.6    +      -       -      -
     20A  ASP*     4.1     7.8    -      -       -      +
    243A  GLY*     6.0     1.6    -      -       -      -
    245A  LYS      2.8    19.9    +      -       -      +
    246A  ILE*     3.6    11.0    +      -       +      +
    248A  VAL*     1.3    78.3    -      -       -      +
    250A  THR*     1.3    62.0    +      -       +      +
    262A  PHE*     5.0     9.7    +      -       +      +
    263A  SER*     4.7     1.9    +      -       -      -
    354A  THR      4.5     1.2    -      -       -      +
    355A  ALA      4.4     0.7    -      -       -      +
    358A  GLY*     3.9     5.7    +      -       -      -
    359A  HIS*     3.0    62.8    +      -       +      +
    360A  PHE      4.4     0.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 250 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    123A  PHE      5.7     1.8    -      -       -      +
    134A  MSE      4.1    16.8    -      -       -      +
    138A  ILE*     4.2     4.2    -      -       -      +
    142A  HIS*     4.9     1.9    -      -       -      -
    246A  ILE      3.2     8.0    +      -       -      +
    247A  ILE*     3.1    16.5    +      -       -      +
    248A  VAL      3.9     3.8    -      -       -      +
    249A  ASP*     1.3    78.7    -      -       +      +
    251A  TYR*     1.3    87.8    +      -       +      +
    252A  GLY      3.7     0.4    +      -       -      -
    253A  GLY      5.4     0.2    +      -       -      -
    255A  ALA      5.7     1.0    +      -       -      -
    256A  ARG      5.3     0.7    +      -       -      -
    257A  HIS*     3.4    35.6    +      -       +      +
    262A  PHE*     4.1    15.9    -      -       +      -
    358A  GLY*     5.6     0.2    -      -       -      -
    359A  HIS      5.3     0.2    +      -       -      -
    360A  PHE*     3.9    22.7    +      -       +      +
----------------------------------------------------------
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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