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Updated: Jul 19, 2026
07:30
Homogeneous Time-resolved Förster Resonance Energy Transfer-based Assay for Detection of Insulin Secretion
Published on: May 10, 2018
Insulin association in neutral solutions studied by light scattering.
1Department of Chemistry, Risø National Laboratory and Roskilde University, DK-4000 Roskilde, Denmark.
Biophysical Chemistry
|February 1, 1991
Summary
Zinc stabilizes insulin hexamers, influencing its molecular weight and distribution. Sulfated insulin remains monomeric, while zinc-free and 2Zn insulins show intermediate states, highlighting zinc's crucial role in insulin structure.
Area of Science:
- Biochemistry
- Protein chemistry
- Structural biology
Background:
- Insulin exists in various oligomeric states, influencing its biological activity.
- Zinc is known to play a role in insulin storage and formulation.
Purpose of the Study:
- To investigate the molecular weight and distribution of sulfated, zinc-free, and 2Zn insulins.
- To quantify the effect of zinc on insulin oligomerization.
Main Methods:
- Light scattering
- Refractometry
- Size-exclusion chromatography
- Dynamic light scattering
Main Results:
- Sulfated insulin was monomeric across the tested concentration range.
- Zinc-free and 2Zn insulins exhibited molecular weights between monomeric and hexameric states.
- Zinc significantly stabilizes the insulin hexamer, increasing the dimer-hexamer equilibrium constant by approximately 400-fold.
- The hydrodynamic radius of 2Zn insulin was measured at 5.6 nm, consistent with the hexameric form.
Conclusions:
- Zinc is a critical stabilizer of the insulin hexamer.
- The oligomeric state of insulin is concentration-dependent and influenced by sulfation and zinc content.
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