The use of microcalorimetry to measure thermodynamic parameters of the binding of ligands to insulin

Flow microcalorimetry was used to measure the free energies, enthalpies, and entropies of interactions between the hormone insulin and small ligand molecules or ions. Measurable amounts of heat were obtained for binding of four phenolic preservative molecules--phenol, meta-cresol, resorcinol, and me...

Full description

Saved in:
Bibliographic Details
Published in:Pharmaceutical research 1990-06, Vol.7 (6), p.606-611
Main Authors: MCGRAW, S. E, LINDENBAUM, S
Format: Article
Language:English
Subjects:
Biological and medical sciences
Calorimetry
Chemical Phenomena
Chemistry, Physical
General pharmacology
Insulin - analysis
Ligands
Medical sciences
Pharmaceutical technology. Pharmaceutical industry
Pharmacology. Drug treatments
Protein Conformation
Thermodynamics
Zinc - analysis
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Flow microcalorimetry was used to measure the free energies, enthalpies, and entropies of interactions between the hormone insulin and small ligand molecules or ions. Measurable amounts of heat were obtained for binding of four phenolic preservative molecules--phenol, meta-cresol, resorcinol, and methylparaben--to both two-zinc and zinc-free insulin and for binding of zinc ions to zinc-free insulin. All of the reactions were spontaneous, but the phenolic binding was driven by enthalpy, while that of zinc was entropy-driven. A combination of van der Waals interactions, hydrophobic effects, and protein conformational changes appeared to be involved in binding of the phenolic ligands. Zinc ions displayed two types of binding to insulin, both involving ion-dipole interactions.
ISSN:0724-8741
1573-904X
DOI:10.1023/A:1015866127447