Chromobacterium violaceum LuxR-type transcriptional regulator (CviR)

CviR is a LuxR-type transcriptional regulator found in the Gram-negative bacterium Chromobacterium violaceum, serving as a master regulator of quorum sensing (UniProt Q7NSC5). It functions by binding to its cognate signaling molecule, N-hexanoyl-L-homoserine lactone (C6-HSL), which triggers the protein to homodimerize and bind to specific DNA sequences to activate the transcription of virulence-related genes, including the vioABCDE operon responsible for the purple pigment violacein (Chen et al., 2011, PDB 3QP1). As a central controller of bacterial pathogenicity that does not directly impact cell viability, CviR is a prime target for the development of 'quorum-quenching' or anti-virulence therapies aimed at treating infections while minimizing the selective pressure that leads to antibiotic resistance (Swem et al., 2009). Research has identified several small-molecule antagonists, including synthetic AHL analogs and repurposed drugs like clozapine, which can effectively block CviR-mediated communication and attenuate bacterial virulence in laboratory models (McInnis & Blackwell, 2011).

Other names

CviR proteinQuorum-sensing transcriptional reporter CviRN-acyl-homoserine lactone-dependent transcriptional regulator CviRLuxR family transcriptional regulator

Competitive antagonism of the N-acyl homoserine lactone (AHL) binding site, preventing receptor dimerization and subsequent DNA binding to inhibit virulence gene transcription.