Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly 2  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Hetero 4-mer - A2B2 

Biological assembly 2 generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 5.67 kDa 
• Atom Count: 478 
• Modelled Residue Count: 50 
• Deposited Residue Count: 50 
• Unique protein chains: 2

3U4N

A novel covalently linked insulin dimer

• PDB DOI: 10.2210/pdb3U4N/pdb

• Classification: HORMONE
• Organism(s): Homo sapiens
• Mutation(s): Yes 


• Deposited: 2011-10-10 Released: 2012-04-11 
• Deposition Author(s): Norrman, M., Vinther, T.N.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.98 Å
• R-Value Free: 0.217 
• R-Value Work: 0.167 
• R-Value Observed: 0.170 

Literature

Novel covalently linked insulin dimer engineered to investigate the function of insulin dimerization.

Vinther, T.N., Norrman, M., Strauss, H.M., Huus, K., Schlein, M., Pedersen, T.A., Kjeldsen, T., Jensen, K.J., Hubalek, F.

(2012) PLoS One 7: e30882-e30882

• PubMed: 22363506 
• DOI: 10.1371/journal.pone.0030882
• Primary Citation of Related Structures:  
  3U4N


• PubMed Abstract: 
  

An ingenious system evolved to facilitate insulin binding to the insulin receptor as a monomer and at the same time ensure sufficient stability of insulin during storage. Insulin dimer is the cornerstone of this system. Insulin dimer is relatively weak, which ensures dissociation into monomers in the circulation, and it is stabilized by hexamer formation in the presence of zinc ions during storage in the pancreatic β-cell. Due to the transient nature of insulin dimer, direct investigation of this important form is inherently difficult. To address the relationship between insulin oligomerization and insulin stability and function, we engineered a covalently linked insulin dimer in which two monomers were linked by a disulfide bond. The structure of this covalent dimer was identical to the self-association dimer of human insulin. Importantly, this covalent dimer was capable of further oligomerization to form the structural equivalent of the classical hexamer. The covalently linked dimer neither bound to the insulin receptor, nor induced a metabolic response in vitro. However, it was extremely thermodynamically stable and did not form amyloid fibrils when subjected to mechanical stress, underlining the importance of oligomerization for insulin stability.

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Organizational Affiliation: 

Diabetes Research Unit, Novo Nordisk A/S, Novo Nordisk Park, Måløv, Denmark.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Insulin A chain	A	21	Homo sapiens	Mutation(s): 0  Gene Names: INS
UniProt & NIH Common Fund Data Resources
Find proteins for P01308 (Homo sapiens) Explore P01308  Go to UniProtKB:  P01308
PHAROS:  P01308

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Insulin B chain	B	29	Homo sapiens	Mutation(s): 1  Gene Names: INS
UniProt & NIH Common Fund Data Resources
Find proteins for P01308 (Homo sapiens) Explore P01308  Go to UniProtKB:  P01308
PHAROS:  P01308

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.98 Å
• R-Value Free: 0.217 
• R-Value Work: 0.167 
• R-Value Observed: 0.170 
• Space Group: I 2₁ 3

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 77.942	α = 90
b = 77.942	β = 90
c = 77.942	γ = 90

Software Package:

Software Name	Purpose
MOLREP	phasing
REFMAC	refinement
HKL-2000	data reduction
HKL-2000	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2011-10-10 
• Released Date: 2012-04-11 
Deposition Author(s): Norrman, M., Vinther, T.N.

Revision History  

• Version 1.0: 2012-04-11
  Type: Initial release