Sensor histidine kinase QseC (QseC)

Sensor histidine kinase QseC is a transmembrane receptor found in various Gram-negative bacteria, including Enterohemorrhagic Escherichia coli (EHEC) and Salmonella enterica (UniProt P0A9I1). It functions as a key component of a two-component signaling system that detects the bacterial quorum-sensing signal autoinducer-3 (AI-3) as well as the host stress hormones epinephrine and norepinephrine (Clarke et al., 2006, PNAS). Upon activation, QseC undergoes autophosphorylation and transfers the phosphate group to its cognate response regulator, QseB, which then modulates the transcription of numerous virulence genes involved in attachment, toxin production, and motility (Rasko et al., 2008, Science). Because QseC coordinates the transition from a commensal to a pathogenic state, it has emerged as a promising target for anti-virulence therapy. Drugs like LED209 aim to inhibit QseC signaling to prevent infection without exerting the strong selective pressure for resistance typically associated with traditional bactericidal antibiotics (Rasko et al., 2008, Science). This approach targets the ability of the pathogen to cause disease rather than its viability, potentially preserving the host's natural microbiome.

Other names

Quorum-sensing Escherichia coli regulator CSensor protein QseCHistidine kinase QseC

Inhibition of sensor histidine kinase autophosphorylation and subsequent signal transduction to response regulators (Rasko et al., 2008, Science).