Contacts of the helix formed by residues 168 - 181 (chain A) in PDB entry 1A9Q


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 ARG 168 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    164A  ASP*     2.9    48.3    +      -       -      +
    166A  TYR      3.7     7.6    -      -       -      -
    167A  ASP*     1.3    92.8    +      -       -      +
    169A  ASP*     1.3    75.7    +      -       -      +
    171A  ARG*     3.2    23.7    +      -       -      +
    172A  GLN*     3.1    24.3    +      -       -      +
    229A  ARG*     5.2     4.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 169 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    167A  ASP*     3.3    11.4    +      -       -      +
    168A  ARG*     1.3    83.9    +      -       -      +
    170A  MET*     1.3    65.6    +      -       +      +
    172A  GLN*     3.2    11.6    +      -       -      +
    173A  LYS*     3.0    40.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 170 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110A  THR*     5.3     3.1    -      -       +      -
    167A  ASP*     3.0    27.8    +      -       +      +
    168A  ARG      3.2     0.4    -      -       -      -
    169A  ASP*     1.3    80.7    -      -       +      +
    171A  ARG*     1.3    57.8    +      -       -      +
    173A  LYS*     3.2    18.6    +      -       +      +
    174A  ALA*     2.9    27.7    +      -       -      +
    234A  ARG*     3.6    30.1    -      -       -      -
    236A  PHE*     3.6    38.0    -      -       +      -
    278A  LEU*     5.0     6.4    -      -       +      +
    281A  SER      3.8    23.3    -      -       -      +
    282A  ILE*     3.9    26.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 171 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    131A  LEU*     4.1    12.3    -      -       +      -
    132A  ILE      3.6    20.8    +      -       -      +
    133A  ARG*     3.7    28.5    +      -       -      +
    166A  TYR*     2.9    31.9    +      -       +      +
    167A  ASP      3.3    11.3    +      -       -      +
    168A  ARG*     3.2    26.6    +      -       -      +
    170A  MET*     1.3    75.3    -      -       -      +
    172A  GLN*     1.3    63.6    +      -       -      +
    174A  ALA*     3.5     7.1    +      -       -      +
    175A  HIS*     3.1    31.8    +      -       +      -
    189A  GLU*     3.0    31.3    +      -       -      +
    236A  PHE*     4.4    13.2    -      -       +      -
    237A  GLY      5.8     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 172 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168A  ARG      3.1    14.3    +      -       -      +
    169A  ASP*     3.4    14.1    -      -       -      +
    170A  MET      3.2     0.2    -      -       -      -
    171A  ARG*     1.3    75.1    -      -       -      +
    173A  LYS*     1.3    70.9    +      -       -      +
    175A  HIS*     3.1    22.6    +      -       -      +
    176A  SER*     3.2    17.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 173 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    169A  ASP*     3.0    31.7    +      -       +      +
    170A  MET*     3.5    25.1    -      -       +      +
    172A  GLN*     1.3    80.9    -      -       -      +
    174A  ALA*     1.3    61.7    +      -       -      +
    176A  SER*     3.2     9.9    +      -       -      +
    177A  THR*     3.0    29.6    +      -       -      -
    278A  LEU*     4.4     4.7    -      -       +      -
    281A  SER*     4.2    32.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 174 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    131A  LEU*     3.8    28.9    -      -       +      -
    170A  MET      2.9    16.5    +      -       -      +
    171A  ARG      3.6     6.5    -      -       -      +
    172A  GLN      3.2     0.2    -      -       -      -
    173A  LYS*     1.3    76.9    -      -       -      +
    175A  HIS*     1.3    61.0    +      -       -      +
    177A  THR      3.6     0.2    +      -       -      -
    178A  TRP*     3.1    24.3    +      -       -      +
    187A  LEU*     3.7     4.5    -      -       -      +
    236A  PHE*     3.9    14.4    -      -       +      -
    274A  PHE*     3.7     8.6    -      -       +      -
    278A  LEU*     3.7    14.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 175 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    131A  LEU*     3.5    15.1    -      -       +      +
    171A  ARG*     3.1    22.8    +      -       +      -
    172A  GLN*     3.1    17.9    +      -       -      +
    174A  ALA*     1.3    75.9    -      -       -      +
    176A  SER*     1.3    64.6    +      -       -      +
    178A  TRP*     3.4     4.0    +      -       -      +
    179A  LYS*     3.1    38.5    +      -       -      +
    187A  LEU*     3.7    42.3    -      -       +      +
    188A  GLN      4.8     2.0    -      -       -      -
    189A  GLU*     3.7    22.0    +      -       +      -
----------------------------------------------------------
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Residues in contact with SER 176 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    172A  GLN*     3.2    11.7    +      -       -      -
    173A  LYS*     3.2    12.4    +      -       -      +
    175A  HIS*     1.3    73.8    -      -       -      +
    177A  THR*     1.3    66.5    +      -       -      +
    179A  LYS*     3.1    18.6    +      -       -      +
    180A  GLN*     3.0    33.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 177 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    173A  LYS      3.0    18.9    +      -       -      -
    174A  ALA      3.9     4.3    -      -       -      -
    176A  SER*     1.3    76.7    -      -       -      +
    178A  TRP*     1.3    61.5    +      -       -      +
    180A  GLN*     3.1    17.1    +      -       +      +
    181A  MET*     3.1    20.8    +      -       -      +
    274A  PHE*     4.2    17.5    -      -       +      -
    277A  LEU*     3.5    42.2    +      -       +      -
    278A  LEU*     4.0    11.3    -      -       -      +
    281A  SER*     4.5    11.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 178 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    129A  ILE*     3.7    39.3    -      -       +      -
    174A  ALA      3.1    18.1    +      -       -      +
    175A  HIS      3.6     5.4    -      -       -      +
    177A  THR*     1.3    76.4    -      -       -      +
    179A  LYS*     1.3    67.5    +      -       +      +
    181A  MET*     3.1    22.5    +      -       +      +
    182A  GLY      3.7     2.9    +      -       -      -
    183A  GLU*     3.6    36.8    +      -       +      +
    185A  ARG*     2.8    37.0    +      -       +      -
    186A  GLU*     3.8     4.5    -      -       -      +
    187A  LEU*     3.2    40.8    -      -       +      +
    270A  LYS*     4.2    18.6    -      -       +      -
    274A  PHE*     4.0    28.6    -      +       +      -
----------------------------------------------------------
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Residues in contact with LYS 179 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175A  HIS*     3.1    25.0    +      -       -      +
    176A  SER*     3.1    18.8    +      -       -      +
    178A  TRP*     1.3    79.2    -      -       +      +
    180A  GLN*     1.3    60.9    +      -       +      +
    182A  GLY*     3.0    21.1    +      -       -      -
    183A  GLU      5.7     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 180 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176A  SER*     3.0    22.6    +      -       -      +
    177A  THR*     3.1    19.2    +      -       +      +
    179A  LYS*     1.3    77.1    -      -       +      +
    181A  MET*     1.3    57.3    +      -       -      +
    182A  GLY      3.2     1.9    +      -       -      -
    277A  LEU*     6.1     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 181 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    177A  THR      3.1    13.6    +      -       -      +
    178A  TRP*     3.1    17.6    +      -       +      +
    179A  LYS      3.1     1.0    -      -       -      -
    180A  GLN*     1.3    77.2    -      -       -      +
    182A  GLY*     1.3    64.9    +      -       -      +
    183A  GLU*     3.4    29.3    +      -       +      +
    270A  LYS*     4.0    16.4    -      -       +      +
    273A  GLN*     3.8    35.7    -      -       +      +
    274A  PHE*     3.7    30.5    -      -       +      -
    277A  LEU*     3.6    27.6    -      -       +      -
----------------------------------------------------------
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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