Protects cells from HOCl (hypochlorite) stress but not peroxide or diamide stress. Decreases the intracellular load of reactive oxygen species by up-regulating genes involved in methionine and cysteine biosynthesis and down-regulating Fur-regulated genes involved in iron acquisition. Has also been suggested to down-regulate expression of the flagellar regulon, decreasing motility, but this activity was not confirmed in a second study (PubMed:22223481). Forms dimers, tetramers and possibly dodecameric complexes; oligomerization may be governed by cellular concentrations. DNA-binding seems to decrease oligomerization. Transcription increases throughout growth and is maximal during stationary phase. Is not up-regulated upon exposure to HOCl. Controversial. Hypermotility, up-regulation of flagellar genes and up-regulation of flagellar protein FliC (PubMed:20494990). Decreased viability following HOCl stress; no effect on motility was seen in this study (PubMed:22223481). Belongs to the LysR transcriptional regulatory family.