Isolation of Quorum Quenching Microorganisms and Screening Methods

ALEJANDRA LEONOR VALDEZ; MARIELA A. TORRES; VIOLA, C.M.; LACOSEGLIAZ, MARIANO JOSÉ; CAROLINA DE LOURDES OLEA; LUCÍA I. CASTELLANO DE FIGUEROA; CARLOS G. NIETO PEÑALVER

Quorum Quenching: A Chemical Biological Approach for Microbial Biofilm Mitigation and Drug Development

Royal Society of Chemistry

Año: 2024; p. 303 - 324

Microorganisms utilize different regulatory mechanisms to modulate their gene expression and their physiology in response to the information they perceive from the environment. Among them, quorum sensing (QS) is one of the mechanisms that has received the most attention in the last two decades. QS is a microbial cell-to-cell chemical communication system based on the self-production, release, detection and response to small signaling molecules called autoinducers (AIs) or QS signals. When high cell densities are reached, a critical concentration of the AI signal is also attained. AIs can then be bound by a cognate receptor protein forming a receptor–AI complex that directly or indirectly regulates the expression of multiple genes. Several regulatory mechanisms share these aspects with QS. However, certain particularities have made QS a focus of attention. Notably, the QS signals can be detected by both the producer and the surrounding microbial cells. In this way, QS allows ‘communication’ and the coordination of the gene expression in the population in concordance with the cell density. This mechanism allows the microbial population to behave like a multicellular organism that coordinates its physiology through hormonal communication, for better exploitation of resources, niche colonization and survival. Thus, QS signals appear to be multifunctional signals that drive gene regulation and organismal behavior from the cellular to the holobiont level. In addition to bioluminescence, QS systems regulate other diverse cellular functions, including the production of exoenzymes, siderophores, exopolysaccharide and antibiotics, sporulation, motility, plasmid conjugation and competence. In this chapter, we provide an overview of QS systems and the potentialities of interfering with them and discuss methods for the isolation of QQ microorganisms and the characterization of the respective QQ enzymes.