Contacts of the helix formed by residues 72 - 85 (chain A) in PDB entry 1Q20


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 GLY 72 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70A  LYS      3.4     0.4    -      -       -      -
     71A  SER*     1.3    81.1    -      -       -      +
     73A  THR*     1.3    64.2    +      -       -      +
     74A  THR      3.3     2.7    -      -       -      -
     75A  TRP*     3.1    23.2    +      -       -      +
     76A  MET      3.2     5.0    +      -       -      -
    145A  MET*     3.3    11.3    -      -       -      +
    210A  TYR*     4.1    11.4    -      -       -      -
    314A  A3P      3.1    27.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 73 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  ILE*     4.1    17.9    -      -       +      +
     67A  THR*     2.7    34.2    +      -       -      +
     71A  SER      3.7     0.6    -      -       -      -
     72A  GLY*     1.3    74.4    -      -       -      +
     74A  THR*     1.3    64.9    +      -       -      +
     76A  MET*     3.1     7.0    +      -       -      +
     77A  ILE*     2.8    37.2    +      -       +      +
    103A  TRP*     3.5    31.9    -      -       +      -
    123A  SER*     4.7     1.8    -      -       -      -
    124A  SER      5.7     0.2    -      -       -      +
    125A  HIS*     3.4     6.1    -      -       -      -
    314A  A3P      2.5    24.2    +      -       -      -
    401A  PLO      5.5     0.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 74 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  THR*     1.3    75.6    -      -       -      +
     75A  TRP*     1.3    64.0    +      -       -      +
     77A  ILE*     3.4    11.4    +      -       -      +
     78A  GLU*     3.0    18.2    +      -       -      +
     97A  ILE*     3.7    16.9    -      -       +      +
    249A  MET*     3.5    24.3    -      -       +      +
    255A  SER      4.0    12.8    -      -       -      +
    257A  TYR*     3.8    11.0    +      -       +      -
    272A  PHE*     3.1    19.5    -      -       -      -
    273A  LEU*     4.4     9.9    -      -       +      -
    314A  A3P      2.8    31.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 75 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72A  GLY      3.1    13.8    +      -       -      +
     74A  THR*     1.3    80.3    -      -       -      +
     76A  MET*     1.3    63.8    -      -       -      +
     78A  GLU*     3.1     1.9    +      -       -      +
     79A  ILE*     2.9    41.9    +      -       +      +
    145A  MET*     4.7     0.7    -      -       +      -
    210A  TYR*     3.5    33.7    -      +       -      -
    213A  LEU*     3.6    51.1    -      -       +      -
    214A  GLN*     3.7    24.9    -      -       +      -
    217A  LEU*     4.1    17.5    -      -       +      +
    244A  SER*     3.0    23.3    +      -       -      -
    245A  THR*     5.7     0.7    -      -       -      -
    246A  PHE      5.6     1.3    -      -       -      -
    249A  MET*     4.1     5.4    -      -       -      -
    314A  A3P      3.2    51.6    +      +       +      +
----------------------------------------------------------
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Residues in contact with MET 76 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  ILE*     3.8    30.3    -      -       +      -
     72A  GLY      3.2     1.6    +      -       -      -
     73A  THR      3.1     7.9    +      -       -      +
     75A  TRP*     1.3    78.5    -      -       -      +
     77A  ILE*     1.3    62.9    +      -       -      +
     79A  ILE*     3.2     9.1    +      -       -      +
     80A  ILE*     3.0    37.5    +      -       +      +
    143A  ILE*     3.9    13.9    -      -       +      -
    145A  MET*     4.1    20.1    -      -       +      -
    208A  ILE*     3.5    28.5    -      -       +      -
    213A  LEU*     4.2    15.5    -      -       +      +
    224A  ILE*     3.4    35.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 77 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  ILE*     3.6    22.6    -      -       +      +
     73A  THR*     2.8    39.0    +      -       +      +
     74A  THR*     3.6     9.0    -      -       -      +
     76A  MET*     1.3    76.9    -      -       -      +
     78A  GLU*     1.3    62.8    +      -       -      +
     80A  ILE*     3.4     1.6    +      -       -      +
     81A  CYS*     3.0    36.6    +      -       -      -
     97A  ILE*     3.6    27.8    -      -       +      +
    101A  ALA*     3.6    24.7    -      -       +      +
    103A  TRP*     4.4    10.8    -      -       +      +
    121A  LEU*     4.4     0.6    -      -       +      +
    123A  SER*     3.5    20.6    -      -       -      +
    257A  TYR*     5.3     2.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 78 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74A  THR      3.0     6.2    +      -       -      +
     75A  TRP      3.6     3.8    -      -       -      +
     77A  ILE*     1.3    76.9    -      -       -      +
     79A  ILE*     1.3    64.8    +      -       -      +
     81A  CYS*     3.3     2.7    +      -       -      +
     82A  LEU*     3.1    36.6    +      -       +      +
     92A  ILE*     3.6    16.9    -      -       +      +
     97A  ILE*     4.0     2.6    -      -       +      +
    100A  ARG*     2.8    31.7    +      -       -      -
    243A  HIS      4.2     8.7    -      -       -      +
    244A  SER*     4.8     1.6    -      -       -      +
    249A  MET*     3.5    42.6    -      -       +      +
    252A  ASN*     3.8     6.8    +      -       -      +
    255A  SER*     2.5    34.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 79 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75A  TRP*     2.9    22.3    +      -       +      +
     76A  MET*     3.2    10.3    +      -       -      +
     78A  GLU*     1.3    76.1    -      -       -      +
     80A  ILE*     1.3    58.6    +      -       +      +
     82A  LEU*     3.3     4.5    +      -       -      +
     83A  ILE*     2.9    42.2    +      -       +      +
    213A  LEU*     3.7    31.4    -      -       +      -
    217A  LEU*     3.8    20.9    -      -       +      -
    221A  VAL*     4.3    10.5    -      -       +      -
    224A  ILE*     4.4    17.7    -      -       +      -
    240A  VAL*     3.8     9.9    -      -       +      +
    244A  SER*     3.2    25.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 80 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63A  ILE*     4.5     5.4    -      -       +      -
     65A  ILE*     4.2    15.7    -      -       +      -
     76A  MET*     3.0    31.5    +      -       -      +
     77A  ILE      4.1     2.5    -      -       -      +
     78A  GLU      3.3     0.2    -      -       -      -
     79A  ILE*     1.3    72.2    -      -       +      +
     81A  CYS*     1.3    62.2    +      -       -      +
     82A  LEU      3.1     1.6    -      -       -      -
     83A  ILE*     4.1     5.2    -      -       +      -
     84A  LEU*     2.8    41.5    +      -       +      +
    121A  LEU*     3.9    24.9    -      -       +      -
    143A  ILE*     4.1    25.8    -      -       +      -
    224A  ILE*     4.2    17.7    -      -       +      -
    228A  LEU*     4.3    21.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 81 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77A  ILE*     3.0    30.3    +      -       -      +
     78A  GLU      3.7     2.0    -      -       -      +
     80A  ILE*     1.3    75.5    -      -       -      +
     82A  LEU*     1.3    63.0    +      -       -      +
     84A  LEU*     3.6     3.3    +      -       -      +
     85A  LYS*     3.4    27.4    +      -       -      +
     88A  ASP      5.3     0.2    -      -       -      +
     91A  TRP*     3.8    16.9    -      -       +      -
     92A  ILE*     3.7    23.2    -      -       +      +
    100A  ARG*     3.4    40.8    -      -       -      +
    121A  LEU*     3.9    15.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 82 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78A  GLU*     3.1    20.9    +      -       +      +
     79A  ILE      3.5     7.0    -      -       -      +
     81A  CYS*     1.3    75.0    -      -       -      +
     83A  ILE*     1.3    63.9    +      -       -      +
     85A  LYS*     3.2     5.3    +      -       -      +
     86A  GLU      3.0     4.9    +      -       -      -
     87A  GLY*     2.8    31.4    +      -       -      +
     88A  ASP      4.3     5.2    -      -       -      +
     89A  PRO*     4.2    14.6    -      -       +      -
     92A  ILE*     3.3    32.5    -      -       +      -
    240A  VAL*     3.3    40.6    -      -       +      +
    243A  HIS*     3.5    25.1    -      -       +      -
    244A  SER*     3.4    13.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 83 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     79A  ILE*     2.9    30.3    +      -       +      +
     80A  ILE*     3.1    11.2    +      -       +      +
     82A  LEU*     1.3    75.5    -      -       -      +
     84A  LEU*     1.3    58.3    +      -       +      +
     86A  GLU*     2.9    25.1    +      -       -      +
    221A  VAL*     4.2     5.2    -      -       +      +
    224A  ILE*     3.9    26.9    -      -       +      -
    225A  CYS*     3.7    32.3    -      -       -      +
    228A  LEU*     4.6     8.1    -      -       +      -
    230A  ARG*     4.1    35.1    +      -       +      +
    232A  LEU*     4.2     8.7    -      -       +      +
    240A  VAL*     4.2    16.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 84 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63A  ILE*     4.4    15.9    -      -       +      -
     80A  ILE*     2.8    37.0    +      -       +      +
     81A  CYS      3.8     4.7    -      -       -      +
     82A  LEU      3.3     0.2    -      -       -      -
     83A  ILE*     1.3    74.4    -      -       +      +
     85A  LYS*     1.3    65.0    +      -       +      +
     86A  GLU*     3.5     7.3    +      -       -      +
     91A  TRP*     4.2    22.9    -      -       +      -
    119A  PRO*     4.7    16.4    -      -       +      +
    121A  LEU*     4.3    19.3    -      -       +      -
    230A  ARG*     3.6    51.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 85 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     81A  CYS      3.4    15.6    +      -       -      +
     82A  LEU      3.2     3.3    +      -       -      +
     84A  LEU*     1.3    81.5    -      -       -      +
     86A  GLU*     1.3    69.5    +      -       -      +
     87A  GLY      3.3     1.6    -      -       -      -
     88A  ASP*     3.2    37.4    +      -       +      +
     91A  TRP*     3.8    50.3    -      -       +      -
----------------------------------------------------------
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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