CodY: An Essential Transcriptional Regulator Involved in Environmental Stress Tolerance in Foodborne RMSA24.

(), as the main pathogen in milk and dairy products, usually causes intoxication with vomiting and various kinds of inflammation after entering the human body. CodY, an important transcriptional regulator in , plays an important role in regulating metabolism, growth, and virulence. However, little is known about the role of CodY on environmental stress tolerance. In this research, we revealed the role of CodY in environmental stress tolerance in foodborne RMSA24. mutation significantly reduced the tolerance of to desiccation and oxidative, salt, and high-temperature stresses. However, was more tolerant to low temperature stress due to mutation of . We found that the expressions of two important heat shock proteins-GroEL and DanJ-were significantly down-regulated in the mutant . This suggests that CodY may indirectly regulate the high- and low-temperature tolerance of by regulating the expressions of and . This study reveals a new mechanism of environmental stress tolerance in and provides new insights into controlling the contamination and harm caused by in the food industry.