Contacts of the helix formed by residues 46 - 53 (chain A) in PDB entry 2IHD


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 SER 46 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47A  THR*     1.3    64.0    +      -       -      +
     48A  GLU*     3.2    11.7    -      -       -      +
     49A  GLU*     3.6    23.4    +      -       -      +
     50A  ALA*     2.9    28.1    +      -       -      +
    171A  LEU      4.7     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 47 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  SER*     1.3    77.5    +      -       -      +
     48A  GLU*     1.3    67.5    +      -       -      +
     50A  ALA*     3.3     3.5    +      -       -      +
     51A  THR*     3.0    26.9    +      -       -      -
    171A  LEU      3.8    21.5    -      -       -      +
    172A  LEU*     3.9    27.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 48 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  SER      3.8     7.4    -      -       -      +
     47A  THR*     1.3    82.7    +      -       -      +
     49A  GLU*     1.3    62.4    +      -       -      +
     51A  THR*     3.2     9.3    +      -       -      -
     52A  ARG*     3.0    39.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 49 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  SER*     3.3    23.1    +      -       -      +
     47A  THR      3.3     0.8    -      -       -      -
     48A  GLU*     1.3    79.8    -      -       -      +
     50A  ALA*     1.3    63.3    +      -       -      +
     52A  ARG*     3.0    20.1    +      -       -      +
     53A  TRP*     3.2    45.7    +      -       -      +
     63A  HIS*     3.6    34.2    +      -       +      +
     65A  TYR*     4.0    24.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 50 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  SER      2.9    17.4    +      -       -      +
     47A  THR      3.6     4.5    -      -       -      +
     49A  GLU*     1.3    74.3    -      -       -      +
     51A  THR*     1.3    57.8    +      -       -      +
     53A  TRP*     3.2    24.3    +      -       +      +
    168A  TYR*     2.6    32.7    +      -       +      -
    171A  LEU*     3.7    41.5    -      -       +      +
    172A  LEU      4.3     4.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 51 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47A  THR      3.0    15.2    +      -       -      -
     48A  GLU*     3.4    11.5    -      -       -      -
     50A  ALA*     1.3    77.2    -      -       -      +
     52A  ARG*     1.3    85.3    +      -       -      +
     54A  ALA*     3.1    21.4    +      -       +      +
     55A  ASP*     4.1     4.2    +      -       -      +
    168A  TYR*     3.6     6.5    -      -       -      -
    172A  LEU*     4.2    13.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 52 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48A  GLU*     3.0    31.7    +      -       +      +
     49A  GLU*     3.0    17.5    +      -       -      +
     51A  THR*     1.3   102.6    -      -       -      +
     53A  TRP*     1.3    55.2    +      -       -      +
     55A  ASP*     2.9    56.7    +      -       -      +
     59A  VAL*     3.2    17.9    -      -       +      +
     63A  HIS*     4.4    16.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with TRP 53 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  GLU*     3.2    33.4    +      -       -      -
     50A  ALA*     3.4    18.2    -      -       +      +
     51A  THR      3.2     0.2    -      -       -      -
     52A  ARG*     1.3    77.0    -      -       -      +
     54A  ALA*     1.3    50.2    +      -       -      +
     56A  SER      3.3     9.4    -      -       -      +
     59A  VAL*     4.5     0.2    -      -       -      -
     60A  LEU*     3.8    23.5    -      -       +      +
     63A  HIS*     3.6    25.3    -      +       +      +
     65A  TYR*     3.5    26.5    -      -       +      -
     66A  GLY*     3.3    27.1    -      -       -      -
     69A  ALA*     3.6    17.9    -      -       +      -
    159A  TYR*     2.7    29.6    +      -       -      -
    162A  PHE*     4.2    11.4    -      +       +      -
    163A  LEU*     4.7     1.3    -      -       -      -
    168A  TYR*     3.7    22.2    -      +       +      -
    171A  LEU*     3.5    31.6    -      -       +      -
----------------------------------------------------------
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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