Glutathione (GSH) is an essential component of the glutaredoxin (Grx) system, and it is synthesized by the enzyme glutathione synthase GshF in
Listeria monocytogenes
. GSH plays a crucial role in regulating
Listeria
virulence by modifying the virulence factors LLO and PrfA. In this study, we investigated the involvement of
L. monocytogenes
GshF in oxidative tolerance and intracellular infection. Our findings revealed that the deletion of
gshF
resulted in a significant reduction in bacterial growth
in vitro
when exposed to diamide and copper ions stress. More importantly, this deletion also impaired the efficiency of invasion and proliferation in macrophages and mice organs. Furthermore, GshF influenced global transcriptional profiles, including carbohydrate and amino acid metabolism, particularly those related to the phosphoenolpyruvate-carbohydrate phosphotransferase system (PTS) genes
lmo1997-lmo2004
, under oxidative stress conditions. In the wild-type strain, the transcription of
lmo1997-lmo2004
was notably downregulated in response to copper ions and diamide stress compared to normal conditions. However, in the absence of
gshF
, the transcripts of
lmo1997-lmo2004
were upregulated in response to these stress conditions. Notably, the deletion of
iiB
man
(
lmo2002
) enhanced oxidative stress tolerance to copper ions, whereas overexpression of
iiB
man
reduced this resistance. In conclusion, our study provides the first evidence that
L. monocytogenes
GshF plays a crucial role in bacterial antioxidation through the regulation of
iiB
man
.
IMPORTANCE
Listeria monocytogenes
has developed various mechanisms to withstand oxidative stress, including the thioredoxin and glutaredoxin systems. However, the specific role of the glutathione synthase GshF, responsible for synthesizing GSH in
L. monocytogenes
, in oxidative tolerance remains unclear. This study aimed to elucidate the relationship between GshF and oxidative tolerance in
L. monocytogenes
by examining the efficiency of invasion and proliferation in macrophages and mice organs, as well as analyzing global transcriptional profiles under oxidative stress conditions. The results revealed that GshF plays a significant role in
L. monocytogenes
’ response to oxidative stress. Notably, GshF acts to suppress the transcription of phosphoenolpyruvate-carbohydrate phosphotransferase system genes
lmo1997-lmo2004
, among which
iiB
man
(
lmo2002
) was identified as the most critical gene for resisting oxidative stress. These findings enhance our understanding of how
L. monocytogenes
adapts to its environment and provide valuable insights for investigating the environmental adaptation mechanisms of other pathogenic bacteria.