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Two redox-responsive LysR-type transcription factors in the phytopathogen Agrobacterium tumefaciens

ABSTRACT: Bacteria are constantly exposed to fluctuations in reactive oxygen species (ROS). In particular, pathogenic bacteria encounter elevated ROS-levels during host infection. In our present study we investigated the intricate regulatory interplay of the LysR-type transcriptional regulators LsrB and OxyR in Agrobacterium tumefaciens. OxyR is a widespread thiol-based redox sensor in bacteria, while LsrB is unique to Rhizobiales. Using phenotypic assays and RNA-sequencing under oxidative stress, we unveiled a central role for both regulators in co-regulating key antioxidant pathways, including katG encoding a bifunctional catalase/peroxidase. Furthermore, we provide novel insights into the mechanism of LsrB activation, suggesting that LsrB also functions as a thiol-based redox sensor. In summary, our findings illuminate the LsrB-OxyR system as a critical component of A. tumefaciens' defense against oxidative stress

INSTRUMENT(S):

ORGANISM(S): Escherichia Coli

SUBMITTER: Sina Schäkermann

LAB HEAD: Julia E. Bandow

PROVIDER: PXD055627 | Pride | 2025-04-28

REPOSITORIES: Pride

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			Action	DRS
	240823_LsrB_A1_RA.raw.zip	Raw
	240823_LsrB_A2_O.raw.zip	Raw
	240823_LsrB_B1_RA.raw.zip	Raw
	240823_LsrB_B2_O.raw.zip	Raw
	240826_LsrB_Overview.xlsx	Xlsx

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