Contacts of the helix formed by residues 169 - 180 (chain C) in PDB entry 1IXR


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 THR 169 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    167C  TYR*     3.4     8.6    +      -       -      +
    168C  TYR*     1.3    83.4    -      -       -      +
    170C  PRO*     1.3    78.1    -      -       +      +
    171C  GLU*     2.9    15.4    +      -       -      +
    172C  GLU*     3.0    38.8    +      -       -      +
    173C  LEU*     2.9    12.9    +      -       -      +
    202C  GLY*     5.0     3.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with PRO 170 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    169C  THR*     1.3    88.7    -      -       +      +
    171C  GLU*     1.3    64.6    +      -       -      +
    174C  ALA*     2.6    41.0    +      -       -      +
    194C  LEU*     4.9     7.0    -      -       +      +
    197C  GLY*     3.8    16.7    -      -       -      +
    198C  ARG*     4.3    34.1    -      -       +      +
    202C  GLY*     6.4     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 171 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    169C  THR*     2.9    14.1    +      -       -      +
    170C  PRO*     1.3    96.1    -      -       -      +
    172C  GLU*     1.3    55.9    +      -       +      +
    174C  ALA*     2.9     5.6    +      -       -      +
    175C  GLN*     2.4    40.2    +      -       -      +
    194C  LEU*     4.8    12.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 172 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15C  ILE*     3.4    17.5    -      -       +      +
     16C  GLY*     3.4    32.5    +      -       -      +
     17C  GLN*     3.6     4.5    +      -       -      -
    168C  TYR*     3.7    27.0    -      -       +      +
    169C  THR*     3.0    29.1    +      -       -      +
    171C  GLU*     1.3    80.8    -      -       +      +
    173C  LEU*     1.3    60.4    +      -       -      +
    175C  GLN*     3.0    19.2    -      -       -      +
    176C  GLY      2.9    23.2    +      -       -      -
    204C  MET*     5.1     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 173 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15C  ILE*     5.8     1.1    -      -       +      -
    168C  TYR*     2.8    38.1    -      -       +      +
    169C  THR      2.9    11.3    +      -       -      +
    170C  PRO      4.4     2.0    -      -       -      +
    172C  GLU*     1.3    70.9    -      -       -      +
    174C  ALA*     1.3    60.9    +      -       -      +
    176C  GLY*     3.3     1.4    +      -       -      -
    177C  VAL*     2.8    33.2    +      -       -      +
    197C  GLY*     4.4    10.3    -      -       -      +
    200C  SER*     3.3    15.9    -      -       -      +
    202C  GLY*     3.5     2.5    -      -       -      -
    203C  THR*     2.8    48.5    -      -       -      +
    204C  MET*     3.2    37.6    -      -       +      +
    207C  ALA*     4.1     7.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 174 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    170C  PRO      2.6    23.9    +      -       -      +
    171C  GLU      3.3     2.7    -      -       -      +
    173C  LEU*     1.3    74.2    -      -       -      +
    175C  GLN*     1.3    69.4    +      -       -      +
    177C  VAL*     3.1    24.7    -      -       -      +
    178C  MET*     3.1     6.6    +      -       -      +
    190C  GLU*     4.4     6.8    -      -       -      +
    193C  ALA*     3.8    13.9    -      -       -      +
    194C  LEU*     4.0    22.2    -      -       +      +
    197C  GLY*     3.8    15.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 175 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15C  ILE*     4.0    24.5    -      -       +      +
    171C  GLU      2.4    22.7    +      -       -      +
    172C  GLU*     3.0    24.7    -      -       -      +
    174C  ALA*     1.3    69.4    -      -       -      +
    176C  GLY*     1.3    73.5    +      -       -      +
    178C  MET*     2.8    27.2    +      -       +      +
    179C  ARG*     3.6     4.0    +      -       -      +
    190C  GLU*     5.3     5.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 176 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15C  ILE*     4.5    19.7    -      -       -      -
    172C  GLU      2.9    14.5    +      -       -      -
    173C  LEU      3.3     3.3    +      -       -      -
    175C  GLN*     1.3    77.5    -      -       -      +
    177C  VAL*     1.3    54.2    +      -       -      +
    178C  MET      2.5    14.7    +      -       -      -
    179C  ARG*     2.6    15.0    +      -       -      +
    180C  ASP*     2.6    21.3    -      -       -      +
    204C  MET*     4.9    10.1    -      -       -      -
----------------------------------------------------------
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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
----------------------------------------------------------
    173C  LEU      2.8    25.9    +      -       -      +
    174C  ALA*     3.1    14.6    -      -       -      +
    176C  GLY*     1.3    71.2    -      -       -      +
    178C  MET*     1.3    56.3    +      -       -      +
    180C  ASP*     2.9    36.3    +      -       +      +
    181C  ALA*     3.1     8.3    +      -       -      +
    188C  ILE*     4.8     6.0    -      -       +      +
    193C  ALA*     4.3    11.7    -      -       +      -
    196C  ILE*     4.2    37.5    -      -       +      -
    197C  GLY*     5.1     1.1    -      -       -      +
    204C  MET*     5.6     0.4    -      -       -      +
    207C  ALA*     4.1    24.0    -      -       +      +
    208C  LYS*     5.3     0.4    -      -       -      +
    211C  PHE*     4.9     6.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 178 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    174C  ALA      3.1     8.6    +      -       -      +
    175C  GLN*     2.8    21.1    +      -       +      +
    176C  GLY      2.5     4.4    +      -       -      -
    177C  VAL*     1.3    66.8    -      -       -      +
    179C  ARG*     1.3    88.7    +      -       -      +
    180C  ASP      2.8     4.0    -      -       -      -
    181C  ALA*     2.5    38.2    +      -       -      +
    182C  ARG*     3.9    17.6    +      -       -      +
    187C  ARG*     5.0    13.0    -      -       -      +
    188C  ILE*     5.3     3.4    -      -       -      -
    190C  GLU*     3.8    29.2    -      -       -      +
    193C  ALA*     5.5     3.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 179 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15C  ILE*     5.9     6.7    -      -       +      -
    175C  GLN*     3.6     3.5    +      -       -      +
    176C  GLY*     2.6    14.2    +      -       -      +
    178C  MET*     1.3    96.3    -      -       -      +
    180C  ASP*     1.3    62.7    +      -       -      +
    181C  ALA      3.1     0.8    +      -       -      -
    182C  ARG*     2.7    74.2    +      -       -      +
    183C  LEU*     4.9     0.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 180 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176C  GLY*     2.6    19.5    -      -       -      +
    177C  VAL*     2.9    26.0    +      -       +      +
    178C  MET      2.8     0.6    -      -       -      -
    179C  ARG*     1.3    81.2    -      -       -      +
    181C  ALA*     1.3    54.6    +      -       -      +
    182C  ARG      3.1     5.6    -      -       -      -
    183C  LEU*     2.8    45.2    -      -       +      +
    186C  VAL*     5.2     1.0    -      -       -      +
    204C  MET*     5.7     0.2    -      -       -      +
    207C  ALA      5.1     0.3    -      -       -      +
    208C  LYS*     2.8    36.9    +      -       +      +
    313C  ANP      6.1     1.4    -      -       -      -
----------------------------------------------------------
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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