Structure-Based Insights into the Molecular Mechanisms of LuxR-Type Quorum Sensing Receptors.
TL;DR
Recent structural and mechanistic insights into LuxR-type receptor function are summarized, including interactions with small molecules, protein partners, and DNA, including interactions with small molecules, protein partners, and DNA.
Abstract
Quorum sensing (QS) enables bacteria to coordinate collective behaviors in response to population density. LuxI/R QS systems, common among gram-negative bacteria, consist of a LuxI-type synthase that produces an N-acyl L-homoserine lactone (AHL) signaling molecule and a LuxR-type receptor that senses the AHL. At threshold AHL concentrations, LuxR-type receptors undergo ligand-induced conformational changes that affect DNA binding and target gene transcription. Because of their role in regulating myriad collective behaviors, LuxI/R systems are targets for many applications, including antivirulence strategies and the engineering of beneficial microbiomes. Recent structural studies have led to substantial progress in understanding molecular mechanisms of LuxI/R systems. However, LuxR-type receptors fall into functionally diverse subfamilies for which structural bases remain incompletely understood. In this article, we summarize recent structural and mechanistic insights into LuxR-type receptor function, including interactions with small molecules, protein partners, and DNA. We identify critical knowledge gaps that highlight the need for additional structural and mechanistic information regarding LuxI/R QS.