Contacts of the helix formed by residues 25 - 34 (chain A) in PDB entry 1R18


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 SER 25 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  LYS*     5.0     1.6    -      -       -      -
     23A  ILE*     3.4    10.7    -      -       -      +
     24A  ALA*     1.3    78.8    -      -       -      +
     26A  ASP*     1.3    63.6    +      -       -      +
     27A  ALA*     4.3     7.9    -      -       -      +
     28A  VAL*     2.9    33.8    +      -       -      +
     29A  ALA*     3.3    14.6    +      -       -      +
     70A  GLU*     3.1    10.3    +      -       -      -
     73A  ARG*     4.2    16.1    -      -       -      -
     99A  TYR*     5.0     0.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 26 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  LYS*     2.6    40.0    +      -       -      +
     24A  ALA      4.0     1.9    +      -       -      +
     25A  SER*     1.3    70.3    -      -       -      +
     27A  ALA*     1.3    60.7    +      -       -      +
     29A  ALA*     3.2     3.2    +      -       -      +
     30A  GLN*     2.9    35.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 27 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  SER*     3.3     5.0    -      -       -      +
     26A  ASP*     1.3    79.8    -      -       -      +
     28A  VAL*     1.3    62.4    +      -       -      +
     30A  GLN*     3.3     7.0    +      -       -      +
     31A  ALA*     3.1    23.7    +      -       -      +
     99A  TYR*     3.6    31.1    -      -       +      +
    102A  ALA*     6.5     0.9    -      -       +      -
    103A  LYS*     4.2    17.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 28 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23A  ILE*     4.1     8.7    -      -       +      -
     25A  SER*     2.9    27.9    +      -       -      +
     26A  ASP      3.3     0.6    -      -       -      -
     27A  ALA*     1.3    77.7    -      -       -      +
     29A  ALA*     1.3    62.5    +      -       -      +
     31A  ALA*     3.4     3.1    +      -       -      +
     32A  MET*     3.2    30.8    +      -       -      +
     66A  ALA*     4.4     8.7    -      -       -      +
     69A  LEU*     3.8    39.4    -      -       +      +
     70A  GLU*     3.4    22.2    -      -       +      +
     73A  ARG*     4.7     3.1    -      -       +      -
     99A  TYR*     3.9    20.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 29 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14A  ILE*     3.6    19.3    -      -       +      +
     18A  LYS*     4.0    24.9    -      -       +      +
     23A  ILE*     3.8    21.1    -      -       +      +
     25A  SER      3.3     4.9    +      -       -      +
     26A  ASP      3.2     9.3    +      -       -      +
     28A  VAL*     1.3    79.5    -      -       -      +
     30A  GLN*     1.3    57.6    +      -       +      +
     32A  MET*     3.4     0.9    +      -       -      -
     33A  LYS*     2.8    38.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 30 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  LYS*     6.0     0.6    +      -       -      +
     26A  ASP*     2.9    23.1    +      -       +      +
     27A  ALA*     3.7     7.6    -      -       -      +
     29A  ALA*     1.3    75.9    -      -       +      +
     31A  ALA*     1.3    65.6    +      -       -      +
     33A  LYS*     3.2    24.3    +      -       -      +
     34A  GLU*     3.0    52.8    +      -       -      +
    102A  ALA*     6.4     2.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 31 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  ALA      3.1    16.3    +      -       -      +
     28A  VAL*     3.8     4.3    -      -       -      +
     30A  GLN*     1.3    76.3    -      -       -      +
     32A  MET*     1.3    61.4    +      -       -      +
     34A  GLU*     3.5     4.8    +      -       -      +
     35A  THR*     3.1    27.7    +      -       -      -
     69A  LEU*     5.2     3.4    -      -       +      -
     95A  CYS*     3.8    27.9    -      -       +      +
     98A  ARG*     4.4    10.3    -      -       -      +
     99A  TYR*     3.9    23.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 32 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  ASN*     3.0    15.2    -      -       -      +
     14A  ILE*     3.7    26.3    -      -       +      +
     17A  LEU*     4.8     2.7    -      -       +      -
     23A  ILE*     4.2    13.7    -      -       -      -
     28A  VAL*     3.2    15.7    +      -       -      +
     29A  ALA      3.8     2.7    -      -       -      +
     31A  ALA*     1.3    77.4    -      -       -      +
     33A  LYS*     1.3    64.7    +      -       -      +
     35A  THR      3.1    12.0    -      -       -      +
     37A  ARG*     6.5     0.2    -      -       -      -
     62A  PRO*     3.5    32.8    -      -       +      +
     65A  HIS*     4.0    14.6    -      -       +      -
     66A  ALA*     4.0    24.7    -      -       +      +
     69A  LEU*     3.7    20.0    -      -       +      -
     91A  TYR*     3.8    22.5    +      -       +      +
     95A  CYS*     4.2     5.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 33 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  ASN*     3.2    17.2    -      -       -      +
     11A  GLU*     4.4    37.6    -      -       +      +
     14A  ILE*     3.8    28.0    -      -       +      +
     15A  ARG*     4.0    20.0    -      -       -      +
     18A  LYS*     5.0     7.7    -      -       -      +
     29A  ALA*     2.8    28.4    +      -       -      +
     30A  GLN*     3.2    30.9    +      -       -      +
     32A  MET*     1.3    77.7    -      -       -      +
     34A  GLU*     1.3    60.1    +      -       +      +
     35A  THR      3.2     0.6    -      -       -      -
     36A  ASP*     4.6     1.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 34 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  GLN*     3.0    36.9    +      -       -      +
     31A  ALA*     4.1     1.2    -      -       -      +
     32A  MET      3.3     0.2    -      -       -      -
     33A  LYS*     1.3    76.8    -      -       +      +
     35A  THR*     1.3    59.8    +      -       -      +
     36A  ASP      3.8     2.5    +      -       -      -
     98A  ARG*     3.2    46.3    +      -       -      +
    101A  LYS*     5.0     9.2    +      -       -      -
    102A  ALA*     6.0     1.7    -      -       -      +
    131A  ASP*     4.7     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