Oenococcus oeni response to wine stress: role of glutathione and thioredoxin systems

This research was focused on Oenococcus oeni adaptation to the crucial first hours after the inoculation before the wine malolactic fermentation (MLF) starts. Several flexible regions in the pan-genome of O. oeni harbouring genes related to wine stress were identified. Moreover, using microarrays and two proteomic techniques (2D-DIGE and iTRAQ labeling), several genes, proteins and main functions affected during acclimation to wine like medium were detected. For the first time in O. oeni, the two complete systems involved in oxidative response, glutathione (GSH) and thioredoxin (Trx) were studied. GSH uptake was defined as strain dependent manner in this species, conferring a beneficial effect and provoking physiological changes to the cell membrane. The general study and transcriptional analysis of genes from GSH and Trx systems was accomplished under wine stress conditions, revealing that Trx system was activated during MLF. Results contribute to a better global view of the response of O. oeni during adaptation to wine conditions.