CHARACTERIZATION OF A BAROTOLERANT MUTANT OF THE YEAST SACCHAROMYCES-CEREVISIAE - IMPEDANCE OF TREHALOSE CONTENT AND MEMBRANE FLUIDITY

A barotolerant mutant of Saccharomyces cerevisiae and its parent were compared with respect to the barotolerance of each strain, intracellul ar content of trehalose, amounts of three major heat shock proteins (h sps), relative proportion of unsaturated and saturated fatty acids in membrane phospholipids, and membrane fluidity. Changes in the amount o f trehalose, but not hsps, were associated with changes in the barotol erance of each strain during the different phases of growth and with t he difference in barotolerance between the mutant and parent strain. T he membrane fluidity in the case of the mutant was low, while that of the parent was high. These results suggest that accumulation of trehal ose and the condition of the membrane are more important for barotoler ance than accumulation of hsps.