Contacts of the helix formed by residues 178 - 181 (chain I) in PDB entry 1P7G


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 TRP 178 (chain I).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50I  TYR*     4.0     8.5    -      -       -      -
     82I  PHE*     3.6    25.1    -      +       -      -
    139I  VAL*     3.4    27.1    -      -       +      -
    140I  GLY      3.4    19.2    +      -       -      +
    141I  TRP*     3.9     4.7    -      -       -      -
    160I  LYS*     2.9    40.3    +      -       -      -
    161I  HIS*     3.3    28.9    +      +       -      -
    176I  ASP*     2.8    24.1    +      -       -      +
    177I  VAL*     1.3    81.2    -      -       -      +
    179I  GLU*     1.3    66.7    +      -       -      +
    180I  HIS*     3.3    36.8    -      +       +      +
    181I  ALA*     3.0    15.9    +      -       -      +
    182I  TYR*     3.4     3.8    -      -       -      -
    138K  GLY*     3.7    29.6    -      -       -      -
    179K  GLU*     4.3     8.7    -      -       -      -
    190K  ARG*     6.2     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 179 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    139I  VAL*     3.8    13.4    -      -       +      +
    177I  VAL      3.5     0.2    +      -       -      -
    178I  TRP*     1.3    72.0    -      -       -      +
    180I  HIS*     1.3    57.9    +      -       -      +
    181I  ALA      2.9     3.6    +      -       -      -
    182I  TYR*     2.9    24.3    +      -       +      +
    183I  TYR*     2.8    46.5    +      -       +      +
    190I  ARG*     4.8     5.4    +      -       -      +
     46K  HIS*     4.1     6.6    -      -       -      -
    139K  VAL*     4.1     1.4    -      -       -      +
    178K  TRP*     3.9    17.6    -      -       +      -
    179K  GLU*     3.3    26.1    +      -       +      +
    180K  HIS*     2.9    55.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 180 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38I  ILE*     3.9    16.1    -      -       -      +
     41I  LEU*     6.0     0.5    -      -       -      +
     42I  HIS*     3.7    39.7    +      +       -      +
     46I  HIS*     3.3    35.4    +      +       -      +
     50I  TYR*     3.4    18.6    +      -       -      -
     90I  HIS*     4.4     3.0    +      -       -      -
    161I  HIS*     5.2     0.2    -      -       -      -
    176I  ASP*     4.2     1.6    +      -       -      -
    178I  TRP*     3.3    38.7    -      +       +      +
    179I  GLU*     1.3    72.8    -      -       -      +
    181I  ALA*     1.3    63.0    -      -       -      +
    182I  TYR      3.2     1.1    +      -       -      -
    183I  TYR      4.6     1.2    +      -       -      +
    184I  LEU      5.7     0.7    +      -       -      -
    179K  GLU*     2.8    32.7    +      -       -      +
    183K  TYR*     3.4    31.8    +      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 181 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34I  ILE*     4.6     2.9    -      -       -      +
     38I  ILE*     3.5    17.2    -      -       -      +
     42I  HIS*     4.0    16.3    +      -       +      -
    176I  ASP*     3.5    39.9    -      -       -      +
    178I  TRP      3.0    14.3    +      -       -      +
    179I  GLU      2.9     1.0    +      -       -      -
    180I  HIS*     1.3    84.2    -      -       +      +
    182I  TYR*     1.3    59.7    +      -       +      +
    193I  TYR*     3.7    17.7    +      -       +      +
----------------------------------------------------------
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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