Contacts of the helix formed by residues 637 - 643 (chain A) in PDB entry 2XER


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 LEU 637 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    634A  PRO*     3.4    14.8    +      -       +      +
    636A  LEU*     1.3    78.9    -      -       -      +
    638A  SER*     1.3    54.4    +      -       -      +
    640A  PHE*     3.3     3.4    +      -       +      +
    641A  SER*     2.7    39.2    +      -       -      +
    684A  PHE*     3.6    19.1    -      -       +      -
    687A  SER*     4.0    22.9    -      -       -      +
    688A  LEU*     4.4     7.4    -      -       +      +
    691A  ILE*     3.9    28.9    -      -       +      -
    737A  ILE*     3.1    50.3    -      -       +      -
    738A  SER*     4.5     7.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 638 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    634A  PRO      4.7     1.0    +      -       -      -
    635A  CYS      4.6     2.0    +      -       -      -
    637A  LEU*     1.3    78.6    -      -       -      +
    639A  PRO*     1.3    71.0    -      -       -      +
    641A  SER*     3.1    23.0    +      -       -      -
    642A  LEU*     3.3    20.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 639 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    598A  ALA*     3.4    24.5    -      -       +      +
    601A  LEU*     3.5    31.5    -      -       +      +
    602A  PRO*     5.0     4.3    -      -       +      -
    635A  CYS      3.4    15.0    -      -       -      +
    636A  LEU*     3.1    16.8    -      -       -      +
    638A  SER*     1.3    97.7    -      -       -      +
    640A  PHE*     1.3    61.6    +      -       -      +
    642A  LEU*     3.4    11.3    +      -       +      +
    643A  LEU*     3.3    19.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 640 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    597A  VAL*     5.7     0.4    -      -       +      -
    601A  LEU*     3.7    33.4    -      -       +      -
    609A  ALA      4.6     0.2    -      -       -      -
    612A  ILE*     4.5     4.9    -      -       +      -
    613A  LEU*     3.6    56.1    -      -       +      -
    616A  THR*     4.0    20.4    -      -       +      -
    636A  LEU*     3.0    37.0    +      -       +      +
    637A  LEU*     3.8     4.7    -      -       +      +
    639A  PRO*     1.3    74.9    -      -       -      +
    641A  SER*     1.3    66.0    -      -       -      +
    643A  LEU*     3.2    11.7    +      -       +      +
    644A  LEU*     3.1    29.0    +      -       +      +
    684A  PHE*     3.7    27.8    -      +       -      -
    688A  LEU*     4.9    10.1    -      -       +      -
    691A  ILE*     5.7     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with SER 641 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    637A  LEU*     2.7    34.5    +      -       -      +
    638A  SER*     3.1    13.0    +      -       -      -
    640A  PHE*     1.3    75.5    -      -       -      +
    642A  LEU*     1.3    65.0    +      -       -      +
    644A  LEU*     3.2    14.9    +      -       -      +
    645A  TYR*     3.3    25.3    -      -       -      -
    691A  ILE*     4.3    24.2    -      -       -      +
    738A  SER*     5.5     1.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 642 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    602A  PRO*     6.2     3.8    -      -       +      -
    638A  SER*     3.3    23.6    +      -       -      +
    639A  PRO*     3.8     8.7    -      -       +      +
    640A  PHE      3.3     0.2    -      -       -      -
    641A  SER*     1.3    77.0    -      -       -      +
    643A  LEU*     1.3    63.7    +      -       -      +
    645A  TYR*     3.2    24.5    +      -       +      +
    646A  HIS*     3.0    24.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 643 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    601A  LEU*     5.2     1.3    -      -       +      -
    606A  THR*     4.1    28.3    -      -       +      +
    609A  ALA*     3.5    50.3    -      -       +      +
    610A  ALA*     3.9     3.8    -      -       -      +
    613A  LEU*     4.1    22.2    -      -       +      -
    639A  PRO      3.3    10.5    +      -       -      +
    640A  PHE*     3.2    18.1    +      -       +      +
    642A  LEU*     1.3    79.5    -      -       -      +
    644A  LEU*     1.3    63.4    +      -       +      +
    646A  HIS*     3.1    19.9    +      -       +      +
    647A  LEU*     3.4    16.9    -      -       +      +
----------------------------------------------------------
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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