Protein and transcript profiling analysis of the response of Yarrowia lipolytica Y‐2 in the degradation of ochratoxin A

Abstract

AbstractThe occurrence of ochratoxin A (OTA) has been reported in cereals, feeds and food. Biological control of OTA has been considered as a promising strategy. Our previous study has shown that Yarrowia lipolytica Y‐2 could degrade OTA. In this study, proteome and transcriptome analysis were performed to investigate the possible mechanisms involved in OTA degradation by Y. lipolytica Y‐2 and the responses of this antagonistic yeast to OTA. The results showed that many proteins and genes involved in removal of reactive O2 species were up‐regulated in Y. lipolytica Y‐2 to respond to the oxidative stress caused by OTA. Also, some proteins and genes involved in the removal of generated toxicants under stress condition were up‐regulated to improve tolerance of this antagonistic yeast to OTA stress. Furthermore, some genes encoding transport proteins and multidrug resistance proteins were up‐regulated significantly to transport and expel OTA from cells and alleviate the toxicity to Y. lipolytica Y‐2. Notably, the gene ECM14 (encoding putative metallocarboxypeptidase ECM14) directly involved in OTA degradation was up‐regulated in Y. lipolytica Y‐2 treated with this mycotoxin. To defend against OTA stress, some genes related to tricarboxylic acid cycle were induced by OTA to generate abundant energy for Y. lipolytica Y‐2. Besides, the down‐regulation of some genes involved in DNA replication and repair decreased the ability of Y. lipolytica Y‐2 to repair DNA damage caused by OTA. These results may imply that OTA degradation by this antagonistic yeast was the synergetic effect of multifarious defence responses to OTA stress.