Contacts of the helix formed by residues 271 - 279 (chain D) in PDB entry 3IAD


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 271 (chain D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    261D  GLU*     3.6    16.3    +      -       -      +
    264D  ASP*     5.3     1.0    +      -       -      +
    269D  GLY      3.9     7.6    +      -       -      -
    270D  LEU*     1.3    74.1    -      -       -      +
    272D  VAL*     1.3    63.6    +      -       -      +
    274D  ARG*     3.3     9.0    +      -       +      +
    275D  ILE*     3.1    23.3    +      -       -      +
    493D  GLN*     3.3    25.0    +      -       -      -
    494D  LEU*     4.5     0.2    -      -       -      -
    804D  EPE      3.2    52.4    -      -       -      -
    805D  EPE      2.7    33.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 272 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    270D  LEU*     2.9    21.3    +      -       +      +
    271D  HIS*     1.3    69.8    -      -       -      +
    273D  PHE*     1.3    81.5    +      -       +      +
    275D  ILE*     3.2     6.8    +      -       -      +
    276D  ALA*     2.9    26.9    +      -       -      +
    283D  PRO*     4.6     2.4    -      -       +      +
    287D  ILE*     4.0    24.5    -      -       +      -
    329D  ILE*     4.3    12.5    -      -       +      +
    332D  ALA*     4.1    16.6    -      -       +      -
    333D  ASP*     4.4    16.6    -      -       +      +
    336D  GLN*     6.1     0.4    -      -       +      +
    494D  LEU*     4.1     9.1    -      -       +      +
    498D  TRP*     4.2    15.7    -      -       +      +
    805D  EPE      3.7     0.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 273 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    271D  HIS      3.4     0.4    -      -       -      -
    272D  VAL*     1.3    74.4    -      -       +      +
    274D  ARG*     1.3    67.0    +      -       -      +
    276D  ALA*     3.2    10.1    +      -       -      +
    277D  GLU*     3.1    25.9    +      -       -      +
    329D  ILE*     3.7    27.4    -      -       +      -
    494D  LEU*     3.6    29.6    -      -       +      -
    497D  GLN*     3.5    39.3    -      -       +      +
    498D  TRP*     3.5    43.5    -      +       -      -
    501D  ARG*     3.3    32.3    -      -       -      -
    805D  EPE      3.4    19.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 274 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254D  GLN*     5.9     0.2    -      -       -      +
    257D  VAL*     4.5     9.1    -      -       -      +
    261D  GLU*     4.1    13.9    -      -       -      +
    271D  HIS*     3.5    16.6    -      -       +      +
    273D  PHE*     1.3    74.4    -      -       -      +
    275D  ILE*     1.3    57.9    +      -       -      +
    277D  GLU*     3.2    31.0    +      -       -      +
    278D  LEU*     2.9    77.6    +      -       +      +
    805D  EPE      3.1    43.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 275 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    258D  LEU*     4.1    11.8    -      -       +      +
    261D  GLU*     4.0    23.1    -      -       +      -
    262D  LEU*     3.9    18.4    -      -       +      -
    270D  LEU*     3.4    45.8    -      -       +      -
    271D  HIS      3.1    13.3    +      -       -      +
    272D  VAL*     3.2     9.1    +      -       -      +
    274D  ARG*     1.3    72.3    -      -       -      +
    276D  ALA*     1.3    58.4    +      -       -      +
    278D  LEU*     3.9     2.3    -      -       -      +
    279D  SER*     2.8    34.1    +      -       -      -
    283D  PRO*     4.4     4.7    -      -       +      -
    286D  VAL*     4.0    25.6    -      -       +      -
    287D  ILE*     4.2    14.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 276 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    272D  VAL      2.9    12.5    +      -       -      +
    273D  PHE*     3.2    14.8    -      -       -      +
    275D  ILE*     1.3    77.5    -      -       -      +
    277D  GLU*     1.3    58.0    +      -       +      +
    279D  SER*     3.2     6.6    +      -       -      -
    281D  ASN*     2.7    38.1    +      -       -      +
    283D  PRO*     4.0    24.7    -      -       +      +
    329D  ILE*     4.3    19.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 277 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254D  GLN*     4.5     6.5    +      -       -      -
    273D  PHE*     3.1    13.0    +      -       -      +
    274D  ARG*     3.2    22.8    +      -       -      +
    276D  ALA*     1.3    76.4    -      -       +      +
    278D  LEU*     1.3    64.3    +      -       -      +
    279D  SER      3.2     1.1    +      -       -      -
    280D  GLY*     3.5    10.2    +      -       -      -
    281D  ASN      4.9     0.4    -      -       -      +
    805D  EPE      2.9    62.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 278 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254D  GLN*     4.1    40.2    +      -       +      +
    255D  GLU*     5.2     1.4    +      -       -      -
    257D  VAL*     3.8    29.8    -      -       +      +
    258D  LEU*     3.8    31.9    -      -       +      +
    261D  GLU*     3.7    30.3    -      -       +      -
    274D  ARG*     2.9    59.0    +      -       +      +
    275D  ILE      3.4     0.2    +      -       -      -
    277D  GLU*     1.3    75.9    -      -       -      +
    279D  SER*     1.3    58.0    +      -       -      +
    280D  GLY      3.5     1.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 279 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    258D  LEU*     4.0    18.6    -      -       -      -
    275D  ILE      2.8    21.0    +      -       -      -
    276D  ALA      3.2     3.1    +      -       -      -
    277D  GLU      3.2     0.2    -      -       -      -
    278D  LEU*     1.3    75.4    -      -       -      +
    280D  GLY*     1.3    60.7    +      -       -      +
    282D  ARG*     3.0    48.0    +      -       -      +
    283D  PRO      3.6     0.9    -      -       -      -
    286D  VAL*     4.2    13.4    -      -       -      +
----------------------------------------------------------
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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