EFFECT OF HYDROSTATIC-PRESSURE ON A MUTANT OF SACCHAROMYCES-CEREVISIAE DELETED IN THE TREHALOSE-6-PHOSPHATE SYNTHASE GENE

Mutants Saccharomyces cerevisiae deleted on the trehalose-6-phosphate synthase gene (tps1) and their parental wild-type cells were submitted to hydrostatic pressure in the range of 0-200 MPa. Experimental evide nce showed that viability for both strains decreased with increasing p ressure and that tps1 mutants, unable to accumulate trehalose, were mo re sensitive to hydrostatic pressure than the wild-type cells. Additio nally, both tps1 and wild-type cells in the stationary phase, when the re is an accumulation of endogenous trehalose, were more resistant to pressure than proliferating cells. Under these conditions, mutant cell s were also more sensitive to pressure treatment than the wild type. T he present work also showed that mild pressure pretreatment did not in duce hydrostatic pressure resistance (barotolerance) in yeast cells.