Contacts of the helix formed by residues 125 - 129 (chain H) in PDB entry 4IBL


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 GLU 125 (chain H).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124H  PRO*     1.3    75.0    -      -       -      +
    126H  ARG*     1.3    64.8    +      -       -      +
    127H  THR*     4.4    11.1    +      -       -      +
    128H  PHE*     3.8     8.5    -      -       +      +
    129H  SER*     3.0    20.3    +      -       -      -
    235H  ILE*     4.3     5.6    -      -       -      -
    239H  GLN*     6.3     1.1    -      -       -      +
    101L  TYR*     3.1    38.0    +      -       +      +
    113L  ARG*     2.8    46.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 126 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124H  PRO      3.8     1.0    +      -       -      -
    125H  GLU*     1.3    73.1    -      -       -      +
    127H  THR*     1.3    66.0    +      -       +      +
    129H  SER*     2.8    66.3    +      -       +      +
    232H  SER      3.4    17.0    +      -       -      +
    233H  GLN*     2.7    41.3    +      -       -      -
    235H  ILE*     3.9    18.7    -      -       +      +
    236H  GLU*     3.1    43.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 127 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125H  GLU*     3.4     9.8    +      -       -      +
    126H  ARG*     1.3    84.3    -      -       +      +
    128H  PHE*     1.3    67.7    +      -       -      +
    129H  GLU*     2.9    69.8    -      -       +      +
    102L  CYS      5.2     0.9    +      -       -      -
    113L  ARG*     5.7     0.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 128 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124H  PRO*     3.9     7.6    -      -       +      -
    125H  GLU*     3.8    10.7    -      -       +      +
    126H  ARG      3.3     0.2    -      -       -      -
    127H  THR*     1.3    80.3    +      -       -      +
    129H  SER*     1.3   158.5    +      +       -      +
    203H  TYR*     3.7    15.0    -      +       -      -
    208H  TYR*     3.7    28.0    -      +       -      -
     95L  ASN*     3.6    16.8    -      -       -      -
    100L  GLN      3.0    26.5    -      -       -      -
    101L  TYR*     3.5    33.2    -      +       +      -
    102L  CYS      5.4     1.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 129 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124H  PRO*     3.8    18.9    -      -       -      +
    125H  GLU      3.0    18.0    +      -       -      -
    126H  ARG*     3.1     5.1    +      -       -      -
    128H  PHE*     1.3    78.8    -      -       -      +
    129H  GLU*     1.3   108.4    +      -       -      +
    162H  ARG*     5.3     1.2    +      -       -      -
    209H  LEU      4.9     0.5    +      -       -      -
    210H  THR*     4.0    11.6    -      -       -      +
    232H  SER*     3.7    20.9    +      -       -      -
    306H   CL      4.1     3.1    -      -       -      +
----------------------------------------------------------
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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