Contacts of the helix formed by residues 319 - 328 (chain A) in PDB entry 2A1X


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 319 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    320A  LEU*     1.3    63.6    +      -       -      +
    321A  LYS*     3.2    27.8    +      -       -      +
    322A  ASP*     2.9    42.1    +      -       -      +
    323A  ILE*     3.4    19.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 320 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    182A  PRO*     3.9    15.7    -      -       +      -
    292A  VAL*     4.5    11.4    -      -       +      -
    300A  ILE*     3.8    37.2    -      -       +      +
    301A  GLU*     4.4    21.8    -      -       +      +
    319A  ASN*     1.3    75.1    -      -       -      +
    321A  LYS*     1.3    63.7    +      -       -      +
    322A  ASP      3.1     1.0    +      -       -      -
    323A  ILE*     3.3    18.7    +      -       +      +
    324A  TRP*     3.2    53.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 321 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    182A  PRO*     5.8     1.1    -      -       -      +
    289A  TYR*     3.8    44.3    -      -       +      -
    319A  ASN*     3.2    17.4    +      -       -      +
    320A  LEU*     1.3    78.0    -      -       -      +
    322A  ASP*     1.3    73.9    +      -       -      +
    324A  TRP*     3.6     2.4    +      -       -      +
    325A  MET*     2.8    49.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 322 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    319A  ASN*     2.9    40.6    +      -       -      +
    321A  LYS*     1.3    97.1    +      -       -      +
    323A  ILE*     1.3    57.4    +      -       +      +
    325A  MET*     3.5    10.0    -      -       -      +
    326A  PHE*     2.6    56.5    +      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 323 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    319A  ASN*     3.4    30.5    +      -       -      +
    320A  LEU*     3.3    18.1    +      -       +      +
    322A  ASP*     1.3    76.5    -      -       +      +
    324A  TRP*     1.3    62.8    +      -       +      +
    326A  PHE*     4.0     7.5    -      -       +      +
    327A  ARG*     3.1    52.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 324 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    154A  MET*     3.6    35.2    -      -       +      +
    155A  HIS*     3.8    13.9    -      +       +      -
    180A  TYR*     3.4    22.5    +      +       +      -
    181A  PHE*     3.6    23.8    -      +       -      -
    182A  PRO*     3.5    28.7    -      -       +      +
    183A  PHE*     3.7    21.8    -      +       -      -
    289A  TYR*     3.7    23.6    +      +       +      +
    300A  ILE*     5.6     0.4    -      -       -      +
    320A  LEU*     3.2    39.3    +      -       +      +
    323A  ILE*     1.3    79.5    -      -       +      +
    325A  MET*     1.3    59.3    +      -       -      +
    327A  ARG*     3.4    35.9    -      -       -      +
    328A  ALA*     2.9    30.1    +      -       -      +
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Residues in contact with MET 325 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    289A  TYR*     3.3    26.5    -      -       +      +
    321A  LYS*     2.8    53.0    +      -       -      +
    322A  ASP*     3.5    11.7    -      -       -      +
    324A  TRP*     1.3    75.9    -      -       -      +
    326A  PHE*     1.3    62.8    +      -       +      +
    327A  ARG      3.3     0.5    +      -       -      -
    328A  ALA*     3.4    11.8    +      -       -      +
    335A  ARG*     3.8    26.0    +      -       -      +
    337A  ASN      5.3     3.1    -      -       -      +
    338A  LEU      3.8    14.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 326 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    322A  ASP*     2.6    43.8    +      -       +      +
    323A  ILE*     4.0     7.6    -      -       +      +
    325A  MET*     1.3    73.6    -      -       +      +
    327A  ARG*     1.3    56.6    +      -       -      +
    329A  ARG*     2.9    22.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 327 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    122A  GLN*     6.2     0.2    -      -       -      +
    123A  ASP*     2.9    39.4    +      -       -      +
    125A  GLN*     4.1    22.7    -      -       -      +
    153A  ALA      4.4     2.9    -      -       -      +
    154A  MET      3.3    25.6    -      -       -      +
    155A  HIS*     4.4    10.7    +      -       -      +
    156A  THR      6.1     0.2    -      -       -      +
    323A  ILE*     3.1    37.6    +      -       -      +
    324A  TRP*     3.4    51.2    -      -       -      +
    326A  PHE*     1.3    76.3    -      -       -      +
    328A  ALA*     1.3    61.2    +      -       -      +
    329A  ARG*     2.9    20.9    +      -       -      +
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Residues in contact with ALA 328 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152A  MET*     3.6    13.7    -      -       +      -
    153A  ALA      4.0     7.2    -      -       -      -
    154A  MET*     3.5    28.3    -      -       +      +
    289A  TYR*     4.5     4.0    -      -       -      +
    324A  TRP      2.9    17.4    +      -       -      +
    325A  MET      3.4     7.3    +      -       -      +
    327A  ARG*     1.3    78.1    -      -       -      +
    329A  ARG*     1.3    71.2    +      -       -      +
    335A  ARG*     3.9    23.3    +      -       -      +
    338A  LEU      4.9     0.4    -      -       -      +
----------------------------------------------------------
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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