Contacts of the strand formed by residues 121 - 125 (chain A) in PDB entry 1XB2


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 HIS 121 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56A  PRO*     2.9    23.5    +      -       +      +
     57A  HIS*     3.6    25.1    -      +       +      +
     58A  VAL      3.0    25.5    +      -       -      +
    116A  SER*     3.3    21.2    +      -       -      +
    120A  ARG*     1.3    78.5    -      -       -      +
    122A  TYR*     1.3    62.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 122 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57A  HIS*     4.5     3.7    +      -       -      -
     58A  VAL*     3.6    34.8    -      -       +      -
     60A  VAL*     4.3    14.4    -      -       +      -
    114A  GLU*     3.4    10.9    -      -       -      +
    115A  TYR*     2.8    68.9    +      +       +      +
    117A  THR*     3.2    22.4    -      -       +      -
    120A  ARG*     2.7    41.3    +      -       -      -
    121A  HIS*     1.3    73.0    -      -       -      +
    123A  ALA*     1.3    59.8    +      -       -      +
    124A  HIS      3.8     0.7    -      -       -      -
    243A  VAL*     3.4    23.5    -      -       +      +
    244A  ASP*     2.5    34.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 123 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57A  HIS*     3.8    16.6    -      -       -      +
     58A  VAL      2.9    12.7    +      -       -      +
     59A  ASN*     3.3    24.5    -      -       -      +
     60A  VAL*     3.1    26.5    +      -       -      +
    112A  HIS*     4.5    14.8    -      -       +      -
    113A  VAL      3.8     4.9    -      -       -      -
    114A  GLU*     4.3     5.8    -      -       +      +
    122A  TYR*     1.3    71.6    -      -       -      +
    124A  HIS*     1.3    61.1    +      -       -      +
    125A  THR*     3.7     4.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 124 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60A  VAL*     3.5    10.4    -      -       +      +
     62A  THR*     2.6    30.7    +      -       -      -
     73A  LEU*     6.4     0.9    -      -       +      -
     74A  THR*     3.2    32.1    +      -       +      -
     77A  ILE*     4.8     9.6    -      -       +      -
    112A  HIS*     3.4     6.6    +      -       -      -
    113A  VAL*     2.9    46.6    +      -       +      +
    115A  TYR*     2.8    43.6    +      +       +      -
    122A  TYR      3.8     1.2    -      -       -      -
    123A  ALA*     1.3    72.2    -      -       -      +
    125A  THR*     1.3    69.6    +      -       -      +
    126A  ASP*     5.0     3.1    -      -       +      -
    148A  ILE*     3.9    19.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 125 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  ASN*     4.9     1.4    +      -       -      -
     60A  VAL      2.8    12.2    +      -       -      -
     61A  GLY*     3.0     4.7    -      -       -      -
     62A  THR*     2.9    27.9    +      -       -      -
    112A  HIS*     3.9    22.2    +      -       +      +
    123A  ALA      4.1     4.9    +      -       -      -
    124A  HIS*     1.3    78.9    +      -       -      +
    126A  ASP*     1.3    66.0    +      -       -      +
    127A  CYS*     3.7    26.2    -      -       -      +
    133A  TYR*     4.2     6.5    -      -       +      -
    136A  ASN*     4.6     6.5    -      -       -      +
    142A  ALA*     4.1    16.6    -      -       +      +
    144A  LEU*     4.3    12.6    -      -       +      +
----------------------------------------------------------
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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