Quorum sensing signal–response systems in Gram-negative bacteria

Abstract

/ Preface Bacteria use quorum sensing to orchestrate gene expression programmes that underlie collective behaviours. Quorum sensing relies on the production, release, detection and group-level response to extracellular signalling molecules, which are called autoinducers. Recent work has discovered new autoinducers in Gram-negative bacteria, shown how these molecules are recognized by cognate receptors, revealed new regulatory components that are embedded in canonical signalling circuits and identified novel regulatory network designs. In this Review we examine how, together, these features of quorum sensing signal–response systems combine to control collective behaviours in Gram-negative bacteria and we discuss the implications for host–microbial associations and antibacterial therapy.

Quorum sensing controls the Pseudomonas aeruginosa CRISPR-Cas adaptive immune system

“…LasR-3OC12-HSL also activates rhlI and rhlR (28). RhlI synthesizes the AI C4-homoserine lactone (C4-HSL) that, in conjunction with RhlR, activates a second wave of QS genes (20,29).…”

“…QS involves the production, release, and detection of extracellular signal molecules, called autoinducers (AI). QS controls behaviors that require cells to act in synchrony to achieve effective outcomes (20).…”

Short Total Synthesis of Ajoene

“…Ajoene's ability to act as a quorum sensing inhibitor (QSI) was selected as this is one of its more recent remarkable biological properties. Quorum sensing (QS) is a mechanism of cell–cell communication in bacteria facilitated by the secretion and detection of signaling molecules such as N ‐acyl homoserine lactones in Gram‐negative bacteria 12. QS allows bacteria to synchronize specific gene expression, which has an impact on their pathogenicity and is thought to play a significant role in the formation of biofilms.…”

The ultimate and proximate underpinnings of social behavior

“…This conceptual advance has also led to the development of new approaches to discover and study different types of selfish genetic elements, which are now known to be essentially ubiquitous (Burt and Trivers, 2008;Werren, 2011). Likewise, quorum sensing in bacteria, which was initially discovered in the particular context of bioluminescence, is now known across a wide range of bacterial species and biological contexts (Papenfort and Bassler, 2016). In fact, the study of social evolution and behavior in microbes has since become a vibrant field of research and, given the genetic accessibility and scope for experimental evolution in microbes, has provided important insights into how social interactions evolve (Foster, 2010;Strassmann et al, 2011).…”