Listeria monocytogenes SpxA1 is a global regulator required to activate genes encoding catalase and heme biosynthesis enzymes for aerobic growth.
Mol Microbiol
; 114(2): 230-243, 2020 08.
Article
in En
| MEDLINE
| ID: mdl-32255216
ABSTRACT
An imbalance of cellular oxidants and reductants causes redox stress, which must be rapidly detected to restore homeostasis. In bacteria, the Firmicutes encode conserved Spx-family transcriptional regulators that modulate transcription in response to redox stress. SpxA1 is an Spx-family orthologue in the intracellular pathogen Listeria monocytogenes that is essential for aerobic growth and pathogenesis. Here, we investigated the role of SpxA1 in growth and virulence by identifying genes regulated by SpxA1 in broth and during macrophage infection. We found SpxA1-activated genes encoding heme biosynthesis enzymes and catalase (kat) were required for L. monocytogenes aerobic growth in rich medium. An Spx-recognition motif previously defined in Bacillus subtilis was identified in the promoters of SpxA1-activated genes and proved necessary for the proper activation of two genes, indicating this regulation by SpxA1 is likely direct. Together, these findings elucidated the mechanism of spxA1 essentiality in vitro and demonstrated that SpxA1 is required for basal expression of scavenging enzymes to combat redox stress generated in the presence of oxygen.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Transcription Factors
/
Listeria monocytogenes
Type of study:
Prognostic_studies
Language:
En
Journal:
Mol Microbiol
Journal subject:
BIOLOGIA MOLECULAR
/
MICROBIOLOGIA
Year:
2020
Document type:
Article
Affiliation country:
United States