Contacts of the helix formed by residues 13 - 26 (chain A) in PDB entry 2IAI


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 THR 13 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11A  PRO      3.9     1.5    +      -       -      +
     12A  GLU*     1.4    76.8    -      -       -      +
     14A  LEU*     1.3    66.0    +      -       -      +
     15A  LEU*     3.5     8.6    +      -       -      +
     16A  SER*     2.9    29.5    +      -       -      -
     17A  VAL*     3.0    22.2    +      -       -      +
----------------------------------------------------------
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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
----------------------------------------------------------
     13A  THR*     1.3    74.1    -      -       -      +
     15A  LEU*     1.3    64.2    +      -       -      +
     17A  VAL*     3.3     6.3    +      -       +      +
     18A  ALA*     2.9    27.0    +      -       +      +
     35A  LEU*     5.2     6.1    -      -       +      +
     39A  ALA*     3.8    28.0    -      -       +      -
     41A  ILE*     4.8     4.9    -      -       +      -
     46A  ILE*     4.4    20.6    -      -       +      -
     49A  HIS*     3.6    42.2    -      -       +      +
     50A  VAL*     4.4     9.6    -      -       +      -
     56A  LEU*     4.2    24.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 15 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13A  THR*     3.2     7.8    +      -       -      +
     14A  LEU*     1.3    79.8    -      -       -      +
     16A  SER*     1.3    57.0    +      -       -      +
     18A  ALA*     3.3     1.8    +      -       +      +
     19A  VAL*     2.9    38.3    +      -       +      +
     56A  LEU*     3.5    43.6    -      -       +      +
     59A  ARG*     4.1    28.5    -      -       +      +
     60A  ALA      4.1     4.0    -      -       -      +
     63A  ARG*     5.5     4.0    -      -       -      -
    103A  TYR*     4.2    24.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 16 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  GLU*     3.2    14.7    -      -       -      +
     13A  THR*     2.9    37.4    +      -       -      -
     15A  LEU*     1.3    77.3    -      -       -      +
     17A  VAL*     1.3    61.5    +      -       -      +
     19A  VAL*     3.5     5.1    +      -       -      +
     20A  GLN*     3.2    21.1    +      -       -      +
    103A  TYR*     4.4    13.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 17 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  THR*     4.0    20.0    -      -       +      -
     12A  GLU*     3.9    18.8    -      -       +      +
     13A  THR      3.0    18.1    +      -       -      +
     14A  LEU*     3.6    11.2    -      -       +      +
     16A  SER*     1.3    73.4    +      -       -      +
     18A  ALA*     1.3    67.0    +      -       -      +
     20A  GLN*     3.1     9.1    +      -       -      +
     21A  VAL*     3.0    22.8    +      -       +      +
     35A  LEU*     4.6     3.4    -      -       +      +
     38A  ALA*     3.7    18.8    -      -       +      +
     39A  ALA*     3.7    32.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 18 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14A  LEU*     2.9    19.4    +      -       +      +
     15A  LEU*     3.7     5.2    -      -       +      +
     17A  VAL*     1.3    77.7    -      -       -      +
     19A  VAL*     1.3    57.9    +      -       -      +
     21A  VAL*     3.2     2.1    +      -       -      +
     22A  PHE*     2.8    46.0    +      -       +      -
     35A  LEU*     3.7    24.9    -      -       +      -
     56A  LEU*     3.9    26.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 19 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15A  LEU*     2.9    26.1    +      -       +      +
     16A  SER*     3.8     6.7    -      -       -      +
     17A  VAL      3.3     0.2    -      -       -      -
     18A  ALA*     1.3    76.4    -      -       -      +
     20A  GLN*     1.3    63.8    +      -       -      +
     22A  PHE*     3.3     3.8    +      -       +      +
     23A  ILE*     3.0    30.5    +      -       +      +
     60A  ALA*     3.7    20.2    -      -       +      -
    102A  PRO*     3.6    34.1    -      -       +      -
    103A  TYR*     3.7    28.5    -      -       +      -
    106A  LEU*     3.9    16.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 20 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  SER      3.2    12.8    +      -       -      +
     17A  VAL*     3.1    13.1    +      -       -      +
     19A  VAL*     1.3    79.0    -      -       -      +
     21A  VAL*     1.3    61.9    +      -       +      +
     23A  ILE*     3.4     7.5    +      -       -      +
     24A  GLU*     3.1    51.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 21 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  VAL*     3.0    15.3    +      -       +      +
     18A  ALA      3.7     5.2    -      -       -      +
     20A  GLN*     1.3    73.7    -      -       +      +
     22A  PHE*     1.3    60.6    +      -       -      +
     24A  GLU*     3.1     8.7    +      -       -      +
     25A  ARG*     2.8    48.5    +      -       -      +
     30A  THR*     3.6    26.7    -      -       +      +
     34A  HIS*     4.1    10.8    -      -       +      +
     35A  LEU*     3.9    12.1    -      -       +      -
     38A  ALA*     3.5    31.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 22 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  ALA*     2.8    29.5    +      -       +      +
     19A  VAL*     3.7     6.1    -      -       +      +
     21A  VAL*     1.3    77.2    -      -       -      +
     23A  ILE*     1.3    57.2    +      -       -      +
     26A  GLY*     2.8    30.9    +      -       -      -
     27A  TYR*     3.7    29.9    +      +       -      +
     30A  THR*     3.6    35.9    -      -       +      -
     35A  LEU*     4.3     4.3    -      -       +      -
     53A  LYS*     3.6    31.0    -      -       +      -
     56A  LEU*     4.1    12.8    -      -       +      -
     57A  LEU*     3.8    27.6    -      -       +      -
     60A  ALA*     5.6     0.2    -      -       +      -
    106A  LEU*     3.7    32.4    -      -       +      +
    109A  ARG*     4.7     0.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 23 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  VAL*     3.0    24.5    +      -       +      +
     20A  GLN*     3.9     6.7    -      -       -      +
     21A  VAL      3.3     0.2    -      -       -      -
     22A  PHE*     1.3    77.0    -      -       -      +
     24A  GLU*     1.3    68.4    +      -       +      +
     26A  GLY      3.9     2.3    +      -       -      -
    102A  PRO*     3.6    43.1    -      -       +      +
    105A  THR*     4.6     9.4    -      -       +      -
    106A  LEU*     3.7    16.4    -      -       +      -
    109A  ARG*     3.1    38.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 24 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  GLN*     3.1    39.9    +      -       +      +
     21A  VAL*     3.1     8.0    +      -       -      +
     23A  ILE*     1.3    82.2    -      -       +      +
     25A  ARG*     1.3    64.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 25 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  VAL*     2.8    29.2    +      -       +      +
     24A  GLU*     1.3    78.1    -      -       +      +
     26A  GLY*     1.3    61.3    +      -       -      +
     29A  GLY*     4.0    18.3    +      -       -      +
     30A  THR*     3.5     8.5    -      -       -      +
     34A  HIS*     3.4    59.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 26 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  PHE      2.8    17.2    +      -       -      -
     23A  ILE      3.9     2.9    +      -       -      -
     24A  GLU      3.5     1.8    -      -       -      -
     25A  ARG*     1.3    80.7    -      -       -      +
     27A  TYR*     1.3    68.0    +      -       -      -
     28A  ASP      3.3     2.9    -      -       -      -
     29A  GLY      4.0     0.7    -      -       -      -
     30A  THR*     2.9    21.8    +      -       -      -
    109A  ARG*     5.7     4.3    -      -       -      -
----------------------------------------------------------
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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