3BXQ

The structure of a mutant insulin uncouples receptor binding from protein allostery. An electrostatic block to the TR transition


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.30 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.206 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Design of an active ultrastable single-chain insulin analog: synthesis, structure, and therapeutic implications.

Hua, Q.X.Nakagawa, S.H.Jia, W.Huang, K.Phillips, N.B.Hu, S.Q.Weiss, M.A.

(2008) J Biol Chem 283: 14703-14716

  • DOI: 10.1074/jbc.M800313200
  • Primary Citation of Related Structures:  
    3BXQ, 2JZQ

  • PubMed Abstract: 
  • Single-chain insulin (SCI) analogs provide insight into the inter-relation of hormone structure, function, and dynamics. Although compatible with wild-type structure, short connecting segments (<3 residues) prevent induced fit upon receptor binding a ...

    Single-chain insulin (SCI) analogs provide insight into the inter-relation of hormone structure, function, and dynamics. Although compatible with wild-type structure, short connecting segments (<3 residues) prevent induced fit upon receptor binding and so are essentially without biological activity. Substantial but incomplete activity can be regained with increasing linker length. Here, we describe the design, structure, and function of a single-chain insulin analog (SCI-57) containing a 6-residue linker (GGGPRR). Native receptor-binding affinity (130 +/- 8% relative to the wild type) is achieved as hindrance by the linker is offset by favorable substitutions in the insulin moiety. The thermodynamic stability of SCI-57 is markedly increased (DeltaDeltaG(u) = 0.7 +/- 0.1 kcal/mol relative to the corresponding two-chain analog and 1.9 +/- 0.1 kcal/mol relative to wild-type insulin). Analysis of inter-residue nuclear Overhauser effects demonstrates that a native-like fold is maintained in solution. Surprisingly, the glycine-rich connecting segment folds against the insulin moiety: its central Pro contacts Val(A3) at the edge of the hydrophobic core, whereas the final Arg extends the A1-A8 alpha-helix. Comparison between SCI-57 and its parent two-chain analog reveals striking enhancement of multiple native-like nuclear Overhauser effects within the tethered protein. These contacts are consistent with wild-type crystal structures but are ordinarily attenuated in NMR spectra of two-chain analogs, presumably due to conformational fluctuations. Linker-specific damping of fluctuations provides evidence for the intrinsic flexibility of an insulin monomer. In addition to their biophysical interest, ultrastable SCIs may enhance the safety and efficacy of insulin replacement therapy in the developing world.


    Related Citations: 
    • The structure of 2zn pig insulin crystal at 1.5 A resolution
      Baker, E.N., Blujdell, T.L., Cutfield, J.F., Cutfield, S.M., Dodson, E.J., Dodson, G.G., Hodgkin, D., Isaacs, N.W., Reynolds, C.D.
      (1988) Philos Trans R Soc London,ser B 319: 369
    • Structure of insulin in 4-zinc insulin
      Bentley, G., Dodson, E., Dodson, G., Hodgkin, D., Mercola, D.
      (1976) Nature 261: 166
    • Phenol stabilizes more helix in a new symmetrical zinc insulin hexamer
      Derewenda, U., Derewenda, Z., Dodson, E., Dodson, G., Reynold, C., Smith, G., Sparks, C., Swenson, D.
      (1989) Nature 338: 594
    • Toward the active conformation of insulin: stereospecific modulation of a structural swith in the B chain
      Hua, Q.X., Nakagawa, S., Hu, S.Q., Jia, W., Wang, S., Weiss, M.A.
      (2006) J Biol Chem 281: 24900

    Organizational Affiliation

    Department of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
insulin A chainAC21N/AMutation(s): 0 
Find proteins for P01308 (Homo sapiens)
Explore P01308 
Go to UniProtKB:  P01308
NIH Common Fund Data Resources
PHAROS  P01308
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
insulin B chainBD30N/AMutation(s): 1 
Find proteins for P01308 (Homo sapiens)
Explore P01308 
Go to UniProtKB:  P01308
NIH Common Fund Data Resources
PHAROS  P01308
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download Ideal Coordinates CCD File 
B, D
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.30 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.206 
  • Space Group: H 3
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 81.39α = 90
b = 81.39β = 90
c = 34γ = 120
Software Package:
Software NamePurpose
HKL-2000data collection
CNSrefinement
d*TREKdata reduction
d*TREKdata scaling
CNSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-05-20
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance