Contacts of the helix formed by residues 175 - 181 (chain C) in PDB entry 1CX2


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 LYS 175 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    173C  ASP*     2.9    16.1    +      -       -      +
    174C  SER*     1.3    68.9    -      -       -      +
    176C  GLU*     1.3    60.6    +      -       +      +
    177C  VAL      2.8     6.4    +      -       -      -
    178C  LEU*     3.3    27.3    -      -       +      +
    179C  GLU*     2.8    58.5    +      -       -      +
    445C  GLN*     3.0    31.1    +      -       -      +
    446C  ALA*     5.9     0.6    -      -       -      +
    449C  LYS*     3.8    27.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 176 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    173C  ASP*     3.4    26.8    +      -       +      +
    174C  SER      3.1     1.6    -      -       -      -
    175C  LYS*     1.3    78.5    -      -       +      +
    177C  VAL*     1.3    58.7    +      -       -      +
    179C  GLU*     4.9     5.0    -      -       -      +
    180C  LYS*     3.0    47.9    +      -       -      +
    490C  GLU*     4.8     0.5    -      -       -      +
    494C  LEU*     2.8    50.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 177 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    172C  PRO*     3.9    13.0    -      -       +      -
    173C  ASP      2.8    22.4    -      -       -      +
    174C  SER*     2.7     6.0    +      -       -      +
    176C  GLU*     1.3    83.5    -      -       -      +
    178C  LEU*     1.3    59.1    +      -       -      +
    179C  GLU      3.4     0.7    -      -       -      -
    181C  VAL*     2.8    32.0    +      -       +      +
    182C  LEU*     2.9    15.6    +      -       +      +
    452C  ILE*     4.5     4.9    -      -       +      -
    456C  ARG*     4.6     1.6    -      -       -      +
    491C  LEU*     3.9    24.2    -      -       +      -
    494C  LEU*     4.4     2.7    -      -       +      -
    495C  TYR*     3.8    23.1    -      -       +      +
    505C  PRO*     4.0    25.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 178 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    174C  SER      2.6    19.8    +      -       -      +
    175C  LYS*     3.3    43.7    -      -       +      +
    177C  VAL*     1.3    71.7    -      -       -      +
    179C  GLU*     1.3    51.5    +      -       +      +
    182C  LEU*     3.0    19.4    +      -       +      +
    183C  LEU*     2.6    58.8    +      -       +      -
    440C  VAL*     5.6     0.2    -      -       +      -
    445C  GLN*     3.7    23.3    -      -       +      +
    448C  ALA*     4.6     7.6    -      -       +      -
    449C  LYS*     3.5    31.6    -      -       +      +
    452C  ILE*     4.1     5.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 179 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175C  LYS*     2.8    48.9    +      -       +      +
    176C  GLU*     4.9     6.6    -      -       -      +
    178C  LEU*     1.3    75.5    -      -       +      +
    180C  LYS*     1.3    62.4    +      -       +      +
    183C  LEU*     3.7    26.6    +      -       +      -
    185C  ARG*     2.7    36.0    +      -       -      +
    445C  GLN*     5.2     1.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 180 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175C  LYS      3.6     1.5    +      -       -      +
    176C  GLU*     3.0    59.2    +      -       -      +
    177C  VAL      3.8     0.2    +      -       -      -
    178C  LEU      3.7     0.2    -      -       -      -
    179C  GLU*     1.3    78.0    -      -       +      +
    181C  VAL*     1.3    60.9    +      -       +      +
    185C  ARG*     2.9    22.2    +      -       -      +
    438C  ARG*     3.3    15.5    +      -       -      +
    490C  GLU*     2.9    44.6    +      -       +      +
    494C  LEU*     4.8     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 181 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    177C  VAL*     2.8    21.4    +      -       +      +
    180C  LYS*     1.3    76.1    -      -       +      +
    182C  LEU*     1.3    65.0    +      -       +      +
    437C  GLY*     4.3     0.9    -      -       -      -
    438C  ARG*     2.9    31.1    +      -       -      +
    487C  MET*     3.6    37.7    -      -       +      +
    490C  GLU*     4.9     5.4    -      -       +      -
    491C  LEU*     3.6    38.6    -      -       +      +
    494C  LEU*     6.2     0.2    -      -       +      -
    509C  VAL*     3.6    29.4    -      -       +      -
----------------------------------------------------------
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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