N-acyl homoserine lactone-dependent LuxR-type quorum sensing receptor (LuxR-type receptor)

LuxR-type receptors are a family of bacterial transcription factors that serve as the primary sensors for N-acyl homoserine lactone (AHL) signal molecules in Gram-negative bacteria. These receptors are central to the process of quorum sensing, a cell-to-cell communication mechanism that allows bacterial populations to coordinate gene expression in response to changes in cell density. Structurally, LuxR-type receptors typically feature an N-terminal ligand-binding domain and a C-terminal helix-turn-helix DNA-binding domain. At high cell densities, the accumulation of AHLs leads to their binding to the receptor, which often triggers protein folding, dimerization, and subsequent binding to specific DNA sequences (Lux boxes) to activate the transcription of genes involved in virulence, biofilm formation, and motility. Because these receptors regulate the expression of pathogenicity factors without directly affecting bacterial viability, they are highly attractive targets for anti-virulence or quorum-quenching therapeutic strategies. Such approaches aim to disarm pathogens like Pseudomonas aeruginosa and Vibrio species, making them more susceptible to the host immune system and conventional antibiotics while potentially reducing the selective pressure for the development of antimicrobial resistance.

Other names

LuxR-type transcription factorAHL-responsive regulatorLuxR homologLuxR-family proteinLuxR-type HTH regulatorLuxR-like regulator

Competitive inhibition of AHL binding to the N-terminal ligand-binding domain, prevention of receptor dimerization, promotion of receptor degradation (proteolysis), or inhibition of the C-terminal domain's ability to bind DNA, thereby blocking the transcription of quorum-sensing regulated genes [1.1.3, 1.3.2, 1.4.1].