FEATURES

FAMILY

DESCRIPTION

Also known as SPX_BACSU, spx, spxA, yjbD. Global transcriptional regulator that plays a key role in stress response and exerts either positive or negative regulation of genes (PubMed:12642660, PubMed:15659166, PubMed:16885442, PubMed:18662407, PubMed:18687074, PubMed:29271514). Acts by interacting with the C-terminal domain of the alpha subunit of the RNA polymerase (RNAP) (PubMed:12642660, PubMed:15659166, PubMed:18687074, PubMed:20084284). This interaction can enhance binding of RNAP to the promoter region of target genes and stimulate their transcription, or block interaction of RNAP with activator proteins and repress transcription (PubMed:12642660, PubMed:15659166, PubMed:18687074, PubMed:20084284). Exhibits no DNA-binding activity (PubMed:15659166, PubMed:18687074)., Induces the expression of a large number of genes in response to a variety of stress conditions, such as disulfide, heat and cell wall stress, while concurrently repressing transcription of genes involved in various developmental and growth-related pathways during periods of extreme stress (PubMed:12642660, PubMed:14597697). Functions in the oxidative stress response via induction of the transcription of thioredoxin (trxA) and thioredoxin reductase (trxB) during thiol-specific oxidative (disulfide) stress (PubMed:14597697, PubMed:15659166, PubMed:18687074). Mediates response to oxidative stress caused by paraquat (PQ) via induction of the methionine sulfoxide reductase genes, msrA and msrB (PubMed:18662407). Also acts as a transcriptional activator of the bacillithiol (BSH) biosynthesis genes in response to oxidizing conditions and thio-reactive compounds (PubMed:23894131). Involved in heat stress response and thermotolerance development, which results in diminished cellular protein aggregates (PubMed:24417481). Plays an important adaptive role in the cell wall stress response (PubMed:29271514). Participates in sulfate-dependent control of organosulfur metabolism. Negatively controls, via CymR, the expression of the organosulfur utilization operons ytmI, yxeI and ssu, and directly activates yrrT operon expression during growth in medium containing methionine as sole sulfur source (PubMed:16885442). Negatively affects competence and sporulation (PubMed:11703662, PubMed:12028382). Inhibits biofilm formation in response to disulfide stress by repressing biofilm matrix genes (PubMed:30718304). Interacts with the C-terminal domain of the alpha subunit of the RNAP (PubMed:12642660, PubMed:16249335, PubMed:19580872, PubMed:20084284, PubMed:22307755). A single Spx monomer interacts with RNAP to form the transcription activation complex (PubMed:22307755). Interacts with the adapter protein SpxH/YjbH (PubMed:19074380, PubMed:24942655, PubMed:30982633).

EXTERNAL LINKS

spx

Mutations

Mutation(s) distribution

Mutations table