Dissertation/Thesis Abstract

Study of low temperature nondenaturational conformational change of bovine α-chymotrypsin by slow- scanrate differential scanning calorimetry
by Kirby, Erin, M.S., Texas Woman's University, 2013, 38; 1550669
Abstract (Summary)

Slow-scan-rate differential scanning calorimetry of enzymes can detect conformational changes which are under kinetic control and not observable at standard scan rates. This method detected a nondenaturational conformational change of bovine &agr;-chymotrypsin at 286 K. This temperature occurs between bovine physiological temperature of 312 K and x-ray crystallography temperature, typically 277 K. This suggests that there are two conformers of &agr;-chymotrypsin, a low temperature conformation and a physiological temperature conformation. The low-temperature to physiological-temperature conformational change has a high activation energy and thus is temperature dependent. The equilibrium thermodynamic changes suggest a reordering of the enzyme structure to give more favorable inter-residue interactions accompanied by an ordering of the structure but one in which there is no change in associated water molecules. The transition state thermodynamics suggest a very strained transition state but one where, again, no change in water interactions is detectable.

Indexing (document details)
Advisor: Britt, Billy M.
Commitee: Britt, Billy M., Omary, Manal, Sheardy, Richard
School: Texas Woman's University
Department: Chemistry
School Location: United States -- Texas
Source: MAI 52/04M(E), Masters Abstracts International
Subjects: Biochemistry
Keywords: Differential scanning calorimetry, Nondenaturational conformational change
Publication Number: 1550669
ISBN: 9781303662720