30 / 2024-10-12 22:25:34

YjbH mediates the oxidative stress response and infection by regulating SpxA1 and the phosphoenolpyruvate-carbohydrate phosphotransferase system (PTS) in Listeria monocytogenes

The foodborne pathogen Listeria monocytogenes relies on its ability to fine-tune the expression of
virulence factors and stress regulators in response to rapidly changing environments. Here, we
reveal that YjbH, a putative thioredoxin family oxidoreductase, plays a pivotal role in bacterial
adaption to oxidative stress and host infection. YjbH directly interacts with SpxA1, an ArsC family
oxidative stress response regulator, and the deletion of YjbH compromised the oxidative stress
tolerance of L. monocytogenes. Also, YjbH is required for the bacterial spread in host cells and
proliferation in mouse organs, thereby contributing to virulence. Transcriptomic analysis of strains
treated with Cd2+ revealed that most virulence genes and phosphoenolpyruvate-carbohydrate
phosphotransferase system (PTS) genes were significantly downregulated in the absence of YjbH.
However, YjbH inhibits PrfA expression when bacteria were grown in the media, suggesting that
YjbH participates in regulating the virulence genes via a complicated regulatory network involving
PrfA and PTS. Collectively, these findings provide a valuable model for clarifying the roles of
thioredoxins from foodborne pathogens regarding improving survival in the external environment
and, more importantly, successfully establishing infection within the host.