Global proteomic responses of sublethally injured Staphylococcus aureus induced by ohmic heating

Abstract

Ohmic heating (OH) is an emerging thermal processing technique that has been utilized in food industry for sterilization and pasteurization. To deeply understand the sublethal injury and inactivation mechanism on microorganisms by OH, TMT-labeled quantitative proteomic was employed to investigate the responses of injured Staphylococcus aureus in this study. The results indicated that OH could induce the occurrence of injured Staphylococcus aureus cells. There were 145 and 250 differentially expressed proteins (DEPs) observed after OH and water bath heating treatments, respectively, and the majority of DEPs of both treatments were cell membrane proteins. OH caused the osmotic imbalance and membrane damage, inhibited gene expression and decreased the virulence of Staphylococcus aureus. Meanwhile, more energy was required for injured cells to maintain osmotic pressure, repair the damaged membrane and express the specific genes.