Solutes that Protect Staphylococcus aureus against Heat-Induced Injury and Their Effect on Cellular Leakage

A number of compounds including salts, sugars, polyols, and amino acids protected Staphylococcus aureus 196E from injury during heating; additionally, most of the compounds reduced or prevented heat-induced leakage of 260 and 280 nm absorbing materials from the cells. In the presence of polyols (sorbitol, mannitol, xylitol, or glycerol) or fructose, heated cells leaked more ultraviolet-absorbing materials than controls lacking solutes even though the solute-treated cells showed little or no injury. The ability of polyols and fructose to induce leakage of cellular constituents during heating of S. aureus , even though few injured cells were found, suggests that leakage from cells undergoing stress does not always indicate injury.