Contacts of the helix formed by residues 170 - 178 (chain A) in PDB entry 1IZC


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 ASN 170 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  SER*     4.4     1.7    +      -       -      -
     21A  MET*     4.4     0.2    -      -       -      +
     24A  TYR*     3.4    41.6    +      -       +      -
    141A  TYR*     4.6     0.4    -      -       -      -
    154A  PHE*     5.8     0.6    -      -       -      +
    160A  ASP*     3.5    18.2    +      -       -      +
    161A  ALA      3.1    23.0    +      -       -      +
    162A  SER*     3.3    12.7    -      -       -      -
    167A  ASP*     3.0    18.8    +      -       -      -
    168A  PRO      4.6     0.8    +      -       -      -
    169A  TYR*     1.3    80.7    -      -       -      +
    171A  VAL*     1.3    63.2    +      -       -      +
    172A  ALA      3.2     1.8    -      -       -      -
    173A  THR*     2.6    27.3    +      -       -      +
    174A  SER*     3.1    25.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 171 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    141A  TYR*     4.0    37.5    -      -       +      -
    142A  GLY      4.8     5.6    -      -       -      +
    149A  PHE*     4.1    23.3    -      -       +      -
    167A  ASP*     3.1     5.6    +      -       -      +
    169A  TYR*     4.1     9.2    -      -       +      +
    170A  ASN*     1.3    79.3    -      -       -      +
    172A  ALA*     1.3    59.6    +      -       -      +
    174A  SER*     3.5     1.4    +      -       -      -
    175A  ASN*     3.0    35.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 172 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    164A  PHE*     3.7    21.5    -      -       +      -
    167A  ASP*     2.9    22.9    +      -       +      +
    171A  VAL*     1.3    77.5    -      -       -      +
    173A  THR*     1.3    65.9    +      -       -      +
    175A  ASN*     4.9     2.7    -      -       -      -
    176A  ASN*     2.9    41.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 173 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  SER*     3.6    22.8    +      -       -      +
     24A  TYR*     4.3    10.5    -      -       +      -
     25A  PRO*     4.0    11.4    -      -       +      +
    162A  SER*     3.0    15.8    +      -       -      -
    163A  LEU*     4.5     0.7    +      -       -      +
    164A  PHE*     3.6    14.1    -      -       -      -
    167A  ASP*     3.3     1.4    +      -       -      -
    170A  ASN*     2.6    32.9    +      -       -      +
    172A  ALA*     1.3    78.9    -      -       -      +
    174A  SER*     1.3    57.9    +      -       -      +
    177A  HIS*     2.9    52.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 174 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  TYR*     4.6    13.5    -      -       -      -
     25A  PRO*     4.7     6.7    -      -       -      +
    139A  MET      5.9     0.4    -      -       -      -
    140A  TYR*     4.3     2.1    -      -       -      -
    141A  TYR*     3.5    29.4    +      -       -      -
    147A  ARG*     3.6    21.1    +      -       -      -
    170A  ASN      3.1    12.5    +      -       -      -
    171A  VAL      3.8     0.7    -      -       -      -
    173A  THR*     1.3    80.1    -      -       -      +
    175A  ASN*     1.3    63.6    +      -       -      +
    178A  VAL*     3.2    37.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 175 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  ARG*     2.8    22.4    +      -       -      -
    139A  MET      4.7     0.2    -      -       -      +
    140A  TYR*     3.5    17.2    -      -       -      -
    141A  TYR*     3.0    56.2    +      -       -      +
    142A  GLY      4.2     5.1    +      -       -      -
    143A  PRO*     5.0     2.2    -      -       -      +
    144A  ILE*     3.7    31.7    -      -       +      +
    171A  VAL*     3.0    22.5    +      -       +      +
    172A  ALA*     4.3     2.9    -      -       -      +
    174A  SER*     1.3    79.1    -      -       -      +
    176A  ASN*     1.3    64.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 176 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  ASN*     3.8     4.6    +      -       -      +
     29A  ARG*     3.4    32.9    +      -       -      +
    164A  PHE*     3.1    42.1    -      -       +      -
    172A  ALA*     2.9    29.7    +      -       -      +
    175A  ASN*     1.3    83.2    -      -       -      +
    177A  HIS*     1.3    61.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 177 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  TYR      4.7     0.2    -      -       -      -
     19A  SER*     4.3     6.1    -      -       -      -
     25A  PRO*     2.8    30.3    +      -       +      +
     26A  GLY      3.4    13.6    -      -       -      +
     27A  ASN*     3.3    42.8    +      -       +      +
     28A  LEU*     3.5     5.5    +      -       -      +
     29A  ARG*     3.3    21.9    +      -       -      +
    119A  ALA      3.7     4.9    -      -       -      +
    163A  LEU*     4.0    24.4    -      -       +      +
    164A  PHE*     3.6    24.0    -      +       -      -
    173A  THR*     2.9    31.5    +      -       +      +
    176A  ASN*     1.3    84.0    -      -       -      +
    178A  VAL*     1.3    63.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 178 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  PRO*     4.0    19.3    -      -       +      -
     29A  ARG*     2.8    22.2    +      -       -      -
    114A  LEU*     4.0    18.8    -      -       +      -
    118A  ALA      3.9    16.6    -      -       -      +
    119A  ALA      3.3    10.1    -      -       -      +
    120A  GLY      5.0     0.7    -      -       -      +
    121A  ILE*     5.0     0.4    -      -       +      -
    139A  MET*     3.6    30.7    -      -       +      +
    140A  TYR*     2.7    25.7    +      -       +      +
    147A  ARG*     5.2     3.8    -      -       -      +
    174A  SER*     3.2    26.2    +      -       -      +
    176A  ASN      3.7     0.2    -      -       -      -
    177A  HIS*     1.3    76.3    -      -       -      +
    179A  CYS*     1.3    59.2    +      -       -      +
----------------------------------------------------------
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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