Saccharides that protect yeast against hydrostatic pressure stress correlated to the mean number of equatorial OH groups

Several saccharides were found to be significantly effective in providing protection against hydrostatic pressure and high temperature damage in the yeast Saccharomyces cerevisiae. The extent of barotolerance and thermotolerance with seven different sugars showed a linear relationship to their mean number of equatorial OH groups. The same linear relatioship is seen when sugars protect protein molecules against elevated temperatures iii vitro. Some sugars were more effective in providing protection against hydrostatic pressure nearly a hundred times than high temperature. Pre-heat shock treatment on yeast cells induce various stress tolerances. In this report, pre-heat shocked cells showed potent protection against elevated temperature, but these cells showed faint protection against elevated pressure. These results suggest that sugars may protect cells against hydrostatic pressure and high temperature in a similar manner, probably by stabilizing the macromolecule(s), and such type of protection may be suited for pressure stress.