COMPARISON OF STRESSED AND UNSTRESSED YEAST BY DIFFERENTIAL SCANNING CALORIMETRY (DSC) AND SDS-PAGE

Abstract

Heat shock of Saccharomyces yeast strains resulted in the induction of a set of proteins referred to as shock protein (HSPs). SDS-PAGE analysis revealed that at least three induced HSPs were identified in a Saccharomyces cerevisiae CBS 1395 and seven in a Saccharomycespastorianus CBS 1503. One of these HSPs with molecular mass of approximately 41 KDa was also identified in two Illutant strains of Saccharomyces cerevisiae. Differential scanning calorimetry analysis of whole yeast cells revealed that heat shock treatment decreased the enthalpy of denaturation ~(H) of total cellular proteins. A direct correlation between the degree of HSP inducibility and protection against extreme temperatures was observed, These results suggest that prior heat shock treatment protects the protein of yeast cells from elevated temperatures.