Journal ArticleDOI
Kinetic study on the irreversible thermal denaturation of yeast phosphoglycerate kinase
TLDR
The results show that the differential scanning calorimetry transitions for the denaturation of phosphoglycerate kinase are highly distorted by the rate-limited irreversible process, and the use of equilibrium thermodynamics in the analysis of irreversible protein denaturation is questioned.Abstract:
Differential scanning calorimetry transitions for the irreversible thermal denaturation of yeast phosphoglycerate kinase at pH 7.0 are strongly scanning-rate dependent, suggesting that the denaturation is, at least in part, under kinetic control. To test this possibility, we have carried out a kinetic study on the thermal inactivation of the enzyme. The inactivation kinetics are comparatively fast within the temperature range of the calorimetric transitions and can be described phenomenologically by the equation dC/dt = -alpha C2/(beta + C), where C is the concentration of active enzyme at a given time, t, and alpha and beta are rate coefficients that depend on temperature. This equation, together with the values of alpha and beta (within the temperature range 50-59 degrees C) have allowed us to calculate the fraction of irreversibly denatured protein versus temperature profiles corresponding to the calorimetric experiments. We have found that (a) irreversible denaturation takes place during the time the protein spends in the transition region and (b) there is an excellent correlation between the temperatures of the maximum of the calorimetric transitions (Tm) and the temperatures (Th) at which half of the protein is irreversibly denatured. These results show that the differential scanning calorimetry transitions for the denaturation of phosphoglycerate kinase are highly distorted by the rate-limited irreversible process. Finally, some comments are made as to the use of equilibrium thermodynamics in the analysis of irreversible protein denaturation.read more
Citations
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Book ChapterDOI
Thermodynamics of structural stability and cooperative folding behavior in proteins.
Kenneth P. Murphy,Ernesto Freire +1 more
TL;DR: Thermodynamic stability and cooperative interactions in proteins can be determined by hierarchical approach to partition functions, thermodynamic dissection of cooperative interactions, and classification of cooperative forces and mechanisms.
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Theoretical analysis of Lumry-Eyring models in differential scanning calorimetry
TL;DR: It is shown that ligand and protein concentration effects on transitions corresponding to situation C (strongly rate-limited transitions) are similar to those predicted by equilibrium thermodynamics for simple reversible unfolding models.
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Protein kinetic stability.
TL;DR: The experimental evidence supporting widespread kinetic stabilization of proteins is summarized, the role of natural selection in determining this feature is discussed, possible molecular mechanisms responsible for kinetic stability are described and the relation between kinetic destabilization and protein misfolding diseases is highlighted.
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Heat-induced changes in the mechanics of a collagenous tissue: isothermal, isotonic shrinkage.
TL;DR: Data from isothermal free-shrinkage tests wherein bovine chordae tendineae were subjected to temperatures from 65 to 85 degrees C for 120 to 1200 s are presented, revealing four new insights into heat-induced denaturation of a collagenous tissue.
Journal ArticleDOI
Denaturation of collagen via heating: an irreversible rate process.
N T Wright,J D Humphrey +1 more
TL;DR: Various findings on the kinetics of the thermal denaturation of collagen are sought to contrast and to encourage investigators to consider the many open problems in part via a synthesis of results from the diverse literatures.
References
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Book ChapterDOI
Stability of Proteins Small Globular Proteins
TL;DR: The chapter discusses the stability of proteins and presents the results obtained on small compact globular proteins, which represent one single cooperative system, and the temperature-induced changes in protein, denaturational and predenaturational changes inprotein, thermodynamics of protein unfolding, and thermodynamic properties of protein.
Book ChapterDOI
Stability of proteins. Proteins which do not present a single cooperative system
TL;DR: The practical importance of thermodynamic studies of protein stability—that is, its importance not only for understanding the principles of organization of these molecules, but just for obtaining structural information on the domain level is emphasized.
Book ChapterDOI
Scanning microcalorimetry in studying temperature-induced changes in proteins.
Peter L. Privalov,S. A. Potekhin +1 more
Journal ArticleDOI
Folding and association of proteins
TL;DR: For small proteins successive stages in the folding have been resolved kinetically; these suggest that H-bonded elements of secondary structure are formed first, followed by folding steps to generate the complete tertiary structure.