Contacts of the helix formed by residues 12 - 27 (chain A) in PDB entry 1A7A


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 ILE 12 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7A  TYR*     4.1    22.4    -      -       +      +
      9A  VAL*     3.7     9.3    -      -       +      +
     11A  ASP*     1.3    74.3    +      -       -      +
     13A  GLY*     1.3    65.7    +      -       -      +
     14A  LEU      3.1     0.4    -      -       -      -
     15A  ALA*     2.9    21.7    +      -       +      +
     90A  ALA*     3.8    12.1    -      -       -      +
     93A  ALA*     3.7    15.7    -      -       +      -
     94A  LYS*     3.6    39.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 13 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11A  ASP*     2.8    16.9    +      -       -      -
     12A  ILE*     1.3    85.1    -      -       -      +
     14A  LEU*     1.3    60.4    +      -       -      +
     15A  ALA*     3.0     5.2    +      -       -      +
     16A  ALA*     3.9    11.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 14 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  ALA*     5.6     0.7    -      -       +      -
     11A  ASP*     2.8    48.5    +      -       +      +
     13A  GLY*     1.3    75.3    -      -       -      +
     15A  ALA*     1.3    64.8    +      -       -      +
     16A  ALA      3.1     1.8    +      -       -      -
     17A  TRP*     3.1    24.3    +      -       +      +
     18A  GLY*     2.8    20.4    +      -       -      -
     86A  ASN*     3.7    31.2    -      -       +      +
     87A  HIS*     3.5    23.6    -      -       +      +
     90A  ALA*     4.1     2.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 15 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  ILE*     2.9    17.1    +      -       +      +
     13A  GLY      3.0     1.5    -      -       -      +
     14A  LEU*     1.3    75.5    -      -       -      +
     16A  ALA*     1.3    65.6    +      -       -      +
     18A  GLY*     2.9     9.9    +      -       -      -
     19A  ARG*     3.0    14.1    +      -       -      +
     90A  ALA*     3.7     2.9    -      -       -      +
     91A  ALA*     3.9    20.5    -      -       -      +
     94A  LYS*     3.6    42.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 16 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13A  GLY      3.9     9.2    +      -       -      +
     14A  LEU      3.2     0.6    -      -       -      -
     15A  ALA*     1.3    80.7    -      -       -      +
     17A  TRP*     1.3    64.4    +      -       -      +
     19A  ARG*     3.0    14.9    +      -       -      +
     20A  LYS*     3.2    15.8    +      -       +      +
     94A  LYS*     5.7     3.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 17 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14A  LEU*     3.1    24.5    +      -       +      +
     16A  ALA*     1.3    75.8    -      -       -      +
     18A  GLY*     1.3    68.1    +      -       -      +
     20A  LYS*     3.2    21.4    -      -       +      +
     21A  ALA*     3.1    16.3    +      -       -      +
     87A  HIS*     3.5    48.7    +      +       +      -
    351A  MSE      5.8     7.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 18 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14A  LEU      2.8     9.9    +      -       -      -
     15A  ALA      2.9     4.9    +      -       -      -
     17A  TRP*     1.3    79.8    -      -       -      +
     19A  ARG*     1.3    63.6    +      -       -      +
     21A  ALA*     3.0     3.6    +      -       -      +
     22A  LEU*     3.0    21.7    +      -       -      +
     87A  HIS*     3.2    35.6    -      -       -      +
     88A  ALA*     4.4     0.9    -      -       -      -
     91A  ALA*     3.8     9.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 19 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15A  ALA      3.0    12.8    +      -       -      +
     16A  ALA*     3.5     8.5    -      -       -      +
     18A  GLY*     1.3    74.6    -      -       -      +
     20A  LYS*     1.3    67.8    +      -       -      +
     22A  LEU*     3.0    22.0    +      -       -      +
     23A  ASP*     2.6    48.7    +      -       -      +
     26A  GLU*     4.5     6.9    +      -       -      -
     65A  GLU*     2.7    46.0    +      -       -      -
     91A  ALA*     4.0    13.2    +      -       +      +
     94A  LYS*     6.2     4.0    -      -       +      +
     95A  ALA*     4.1    21.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 20 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  ALA*     3.5    16.4    -      -       +      +
     17A  TRP*     3.2    26.5    -      -       +      +
     19A  ARG*     1.3    81.7    -      -       -      +
     21A  ALA*     1.3    62.4    +      -       -      +
     23A  ASP*     3.2    16.9    +      -       -      +
     24A  ILE*     3.1    28.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 21 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  TRP*     3.1     6.7    +      -       -      +
     18A  GLY      3.0     8.3    +      -       -      +
     20A  LYS*     1.3    76.7    -      -       -      +
     22A  LEU*     1.3    67.5    +      -       -      +
     24A  ILE*     3.1     8.7    +      -       -      +
     25A  ALA*     2.8    23.0    +      -       -      +
     58A  VAL*     3.7    28.2    -      -       +      +
     87A  HIS*     3.8    15.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 22 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  GLY      3.0    26.3    +      -       -      +
     19A  ARG*     3.3    24.5    -      -       -      +
     21A  ALA*     1.3    70.4    -      -       -      +
     23A  ASP*     1.3    64.5    +      -       -      +
     25A  ALA*     2.8     4.1    +      -       -      +
     26A  GLU*     2.8    32.7    +      -       +      +
     58A  VAL*     3.7    25.1    -      -       +      +
     61A  ALA*     3.4    35.0    -      -       +      -
     62A  VAL*     4.6     7.0    -      -       +      +
     65A  GLU*     3.1    28.3    -      -       -      +
     88A  ALA*     4.4    11.7    -      -       +      -
     91A  ALA*     4.1    11.0    -      -       +      -
     92A  ILE*     4.7     1.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 23 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  ARG*     2.6    53.2    +      -       -      +
     20A  LYS*     3.2    19.5    +      -       -      +
     22A  LEU*     1.3    73.7    -      -       -      +
     24A  ILE*     1.3    63.6    +      -       +      +
     26A  GLU*     3.7    23.9    +      -       -      +
     27A  ASN*     3.8     9.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 24 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  LYS*     3.1    15.9    +      -       +      +
     21A  ALA*     3.1    11.1    +      -       -      +
     23A  ASP*     1.3    77.0    -      -       +      +
     25A  ALA*     1.3    66.6    +      -       -      +
     26A  GLU      3.1     0.2    -      -       -      -
     27A  ASN*     3.1    20.7    +      -       +      +
     28A  GLU*     3.6    13.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 25 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  ALA      2.8    17.2    +      -       -      +
     22A  LEU      3.5     6.5    -      -       -      +
     24A  ILE*     1.3    74.1    -      -       -      +
     26A  GLU*     1.3    63.2    +      -       -      +
     28A  GLU*     3.0    13.0    +      -       -      +
     29A  MSE      3.1    38.0    -      -       +      +
     58A  VAL*     3.5    22.7    -      -       +      -
     62A  VAL*     4.2     4.5    -      -       +      -
    355A  SER*     3.8    16.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 26 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  ARG*     4.5     6.8    +      -       -      -
     22A  LEU*     2.8    26.9    +      -       -      +
     23A  ASP*     3.8    18.4    -      -       -      +
     24A  ILE      3.1     0.2    -      -       -      -
     25A  ALA*     1.3    78.1    -      -       -      +
     27A  ASN*     1.3    57.6    -      -       -      +
     29A  MSE      3.2    27.0    +      -       -      +
     30A  PRO*     4.4     0.5    -      -       -      +
     33A  MSE      3.2    41.9    -      -       +      +
     36A  ARG*     3.5    21.3    +      -       -      -
     62A  VAL*     4.0    16.1    -      -       +      +
     65A  GLU*     4.5     8.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 27 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23A  ASP      3.8     6.8    +      -       -      +
     24A  ILE*     3.1    14.7    +      -       +      +
     26A  GLU*     1.3    77.3    -      -       -      +
     28A  GLU*     1.3    58.4    +      -       -      +
     29A  MSE      3.5     0.2    -      -       -      -
     30A  PRO*     4.8     2.4    -      -       -      +
    401A  LYS*     2.9    39.9    +      -       -      +
----------------------------------------------------------
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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