1IZA

ROLE OF B13 GLU IN INSULIN ASSEMBLY: THE HEXAMER STRUCTURE OF RECOMBINANT MUTANT (B13 GLU-> GLN) INSULIN


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Observed: 0.154 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Role of B13 Glu in insulin assembly. The hexamer structure of recombinant mutant (B13 Glu-->Gln) insulin.

Bentley, G.A.Brange, J.Derewenda, Z.Dodson, E.J.Dodson, G.G.Markussen, J.Wilkinson, A.J.Wollmer, A.Xiao, B.

(1992) J Mol Biol 228: 1163-1176

  • DOI: 10.1016/0022-2836(92)90323-c
  • Primary Citation of Related Structures:  
    1IZA, 1IZB

  • PubMed Abstract: 
  • The assembly of the insulin hexamer brings the six B13 glutamate side-chains at the centre into close proximity. Their mutual repulsion is unfavourable and zinc co-ordination to B10 histidine is necessary to stabilize the well known zinc-containing hexamers ...

    The assembly of the insulin hexamer brings the six B13 glutamate side-chains at the centre into close proximity. Their mutual repulsion is unfavourable and zinc co-ordination to B10 histidine is necessary to stabilize the well known zinc-containing hexamers. Since B13 is always a carboxylic acid in all known sequences of hexamer forming insulins, it is likely to be important in the hormone's biology. The mutation of B13 Glu-->Gln leads to a stable zinc-free hexamer with somewhat reduced potency. The structures of the zinc-free B13 Gln hexamer and the 2Zn B13 insulin hexamer have been determined by X-ray analysis and refined with 2.5 A and 2.0 A diffraction data, respectively. Comparisons show that in 2Zn B13 Gln insulin, the hexamer structure (T6) is very like that of the native hormone. On the other hand, the zinc-free hexamer assumes a quaternary structure (T3/R3) seen in the native 4Zn insulin hexamer, and normally associated only with high chloride ion concentrations in the medium. The crystal structures show the B13 Gln side-chains only contact water in contrast to the B13 glutamate in 2Zn insulin. The solvation of the B13 Gln may be associated with this residue favouring helix at B1 to B8. The low potency of the B13 Gln insulin also suggests the residue influences the hormone's conformation.


    Related Citations: 
    • The Structure of 2Zn Pig Insulin Crystals at 1.5 Angstroms Resolution
      Baker, E.N., Blundell, T.L., Cutfield, J.F., Cutfield, S.M., Dodson, E.J., Dodson, G.G., Crowfoot Hodgkin, D.M., Hubbard, R.E., Isaacs, N.W., Reynolds, C.D., Sakabe, K., Sakabe, N., Vijayan, N.M.
      (1988) Philos Trans R Soc London,ser B 319: 369

    Organizational Affiliation

    Institut Pasteur, Paris, France.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
INSULINA, C21Sus scrofaMutation(s): 0 
Gene Names: INS
UniProt
Find proteins for P01315 (Sus scrofa)
Explore P01315 
Go to UniProtKB:  P01315
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
INSULINB, D30Sus scrofaMutation(s): 1 
Gene Names: INS
UniProt
Find proteins for P01315 (Sus scrofa)
Explore P01315 
Go to UniProtKB:  P01315
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Observed: 0.154 
  • Space Group: H 3
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 80.6α = 90
b = 80.6β = 90
c = 37.6γ = 120
Software Package:
Software NamePurpose
PROLSQrefinement

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

  • Deposited Date: 1992-10-16 
  • Released Date: 1993-10-31 
  • Deposition Author(s): Xiao, B., Dodson, G.G.

Revision History  (Full details and data files)

  • Version 1.0: 1993-10-31
    Type: Initial release
  • Version 1.1: 2008-03-24
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance