Contacts of the helix formed by residues 253 - 266 (chain B) in PDB entry 2IAG


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 253 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    136B  LEU*     3.6    31.2    -      -       -      -
    179B  THR      3.8     7.7    +      -       -      -
    180B  LEU*     2.7    29.9    +      -       -      -
    251B  HIS      3.5     3.4    +      -       -      -
    252B  ARG*     1.3    77.3    -      -       -      +
    254B  LYS*     1.3    63.5    -      -       -      +
    255B  TRP*     3.4     9.7    -      -       -      +
    256B  LEU*     3.0    16.5    +      -       -      +
    257B  GLU*     3.1    21.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 254 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    307A  ALA*     6.0     4.9    -      -       -      +
    127B  THR*     4.0    16.6    -      -       +      +
    132B  GLU*     3.4    45.9    +      -       +      +
    136B  LEU*     5.5     0.2    -      -       -      +
    252B  ARG      3.8     0.8    +      -       -      -
    253B  SER*     1.3    70.6    -      -       -      +
    255B  TRP*     1.3    59.6    +      -       -      +
    257B  GLU*     3.3     9.6    +      -       +      +
    258B  SER*     2.7    53.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 255 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    123B  ARG*     4.6     1.2    +      -       -      -
    124B  MET*     3.5    31.2    -      -       +      +
    127B  THR*     3.6    32.3    +      -       -      +
    128B  LEU*     3.7    28.8    -      -       +      +
    136B  LEU*     5.2     1.1    -      -       +      -
    180B  LEU*     3.9    28.0    -      -       +      -
    181B  TYR*     3.7    25.8    -      +       -      -
    253B  SER*     3.4    16.8    -      -       -      +
    254B  LYS*     1.3    78.5    -      -       -      +
    256B  LEU*     1.3    91.7    +      -       +      +
    258B  SER*     3.5     1.7    +      -       -      -
    259B  TYR*     3.1    31.2    +      +       +      +
    277B  LEU*     5.6     0.4    -      -       +      -
    280B  GLN*     3.6    45.1    -      -       +      -
    284B  THR*     4.2    13.7    -      -       -      -
    600B  HEM      4.5     4.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 256 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    180B  LEU      3.4    16.8    -      -       -      +
    181B  TYR*     3.9    32.8    -      -       +      +
    246B  LEU*     4.2    17.0    -      -       +      -
    252B  ARG*     3.9    29.2    -      -       +      +
    253B  SER*     3.0    11.0    +      -       -      +
    255B  TRP*     1.3    84.4    -      -       +      +
    257B  GLU*     1.3    61.8    +      -       -      +
    259B  TYR*     3.3     2.9    +      -       +      -
    260B  LEU*     2.9    42.6    +      -       +      +
    277B  LEU*     3.6    31.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 257 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    252B  ARG*     3.4    44.2    +      -       +      +
    253B  SER      3.1    19.4    +      -       -      +
    254B  LYS*     3.9    10.0    -      -       +      +
    256B  LEU*     1.3    76.4    -      -       -      +
    258B  SER*     1.3    58.2    +      -       -      +
    260B  LEU*     3.6     9.3    -      -       -      +
    261B  LEU*     3.0    27.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 258 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    123B  ARG*     3.0    32.0    +      -       -      -
    127B  THR*     3.2    15.1    -      -       -      +
    254B  LYS*     2.7    38.5    +      -       -      +
    255B  TRP      3.5     1.4    +      -       -      -
    257B  GLU*     1.3    74.6    -      -       -      +
    259B  TYR*     1.3    60.2    +      -       -      +
    261B  LEU*     3.6     8.3    -      -       -      +
    262B  HIS*     2.8    29.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 259 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112B  LEU*     4.9     7.3    -      -       +      +
    120B  GLU*     3.8     9.0    -      -       +      -
    123B  ARG*     3.6    15.2    -      -       -      +
    124B  MET*     3.5    26.0    -      -       +      -
    255B  TRP*     3.1    26.4    +      +       +      +
    256B  LEU*     3.7     3.8    -      -       +      +
    258B  SER*     1.3    74.9    +      -       -      +
    260B  LEU*     1.3    58.9    +      -       -      +
    262B  HIS*     3.2    16.4    +      +       -      +
    263B  LEU*     2.9    59.1    +      -       +      +
    276B  ALA*     3.4    26.0    +      -       +      +
    277B  LEU*     4.0    19.1    -      -       +      -
    279B  LEU*     5.4     2.1    -      -       -      +
    280B  GLN*     3.6    36.1    +      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 260 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    243B  PRO*     4.6    11.0    -      -       +      -
    246B  LEU*     5.3     1.1    -      -       +      -
    252B  ARG*     3.4    41.5    -      -       -      +
    256B  LEU*     2.9    35.7    +      -       +      +
    257B  GLU*     3.6     6.1    -      -       -      +
    259B  TYR*     1.3    76.2    -      -       -      +
    261B  LEU*     1.3    56.6    +      -       -      +
    263B  LEU*     3.2     9.2    +      -       +      +
    264B  GLU*     2.9    42.0    +      -       -      +
    273B  GLN*     3.6    21.2    -      -       -      +
    277B  LEU*     4.1    26.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 261 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    257B  GLU      3.0    17.9    +      -       -      +
    258B  SER*     3.6     9.6    -      -       -      +
    260B  LEU*     1.3    74.5    -      -       -      +
    262B  HIS*     1.3    63.5    +      -       -      +
    264B  GLU*     3.5    23.9    +      -       +      +
    265B  GLU*     3.0    57.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 262 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112B  LEU*     6.1     0.6    -      -       -      +
    115B  TYR*     4.6    12.7    -      -       +      -
    120B  GLU*     3.5    44.8    +      -       +      +
    123B  ARG*     3.9    15.5    +      -       -      +
    258B  SER      2.8    21.7    +      -       -      +
    259B  TYR*     3.2    20.1    +      +       -      +
    261B  LEU*     1.3    74.8    -      -       -      +
    263B  LEU*     1.3    64.0    +      -       +      +
    265B  GLU*     3.7    12.7    +      -       -      +
    266B  MET*     3.3    56.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 263 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112B  LEU*     4.5     9.2    -      -       +      -
    259B  TYR*     2.9    64.5    +      -       +      +
    260B  LEU*     3.2    10.7    +      -       +      +
    262B  HIS*     1.3    74.3    -      -       +      +
    264B  GLU*     1.3    62.0    +      -       -      +
    266B  MET*     3.0    36.2    +      -       +      -
    268B  VAL*     3.2    33.3    +      -       +      +
    273B  GLN*     3.9    31.2    -      -       +      +
    276B  ALA*     4.2    16.6    -      -       +      -
    277B  LEU*     4.9     4.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 264 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    260B  LEU*     2.9    31.7    +      -       -      +
    261B  LEU*     3.5    31.1    -      -       +      +
    263B  LEU*     1.3    76.2    -      -       -      +
    265B  GLU*     1.3    57.2    +      -       +      +
    267B  GLY*     3.2    16.6    +      -       -      +
    268B  VAL      4.6     2.0    -      -       -      +
    273B  GLN*     4.0    21.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 265 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    261B  LEU*     3.0    52.0    +      -       +      +
    262B  HIS*     3.7    12.7    +      -       -      +
    264B  GLU*     1.3    76.3    -      -       +      +
    266B  MET*     1.3    59.2    +      -       +      +
    267B  GLY      3.3     1.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with MET 266 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112B  LEU*     4.3    14.6    -      -       +      -
    113B  PRO*     3.6    36.0    -      -       +      +
    114B  HIS      4.6     3.8    -      -       -      +
    115B  TYR*     3.9    29.4    -      -       +      -
    262B  HIS*     3.3    44.4    +      -       +      +
    263B  LEU*     3.0    24.4    +      -       +      +
    265B  GLU*     1.3    78.2    -      -       +      +
    267B  GLY*     1.3    60.2    +      -       -      +
    268B  VAL*     3.9    12.6    -      -       +      -
----------------------------------------------------------
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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