Quorum Sensing and Quorum Quenching in Soil Ecosystems

Abstract

Several bacteria originating from soil ecosystems have evolved the ability to regulate gene expression as a function of their cell density, a phenomenon called quorum sensing (QS). To do so bacteria communicate via the production and sensing of signal molecules. The most common class of signals clusters N-acyl homoserine lactones (AHL) molecules. They are involved in the regulation of a wide range of bacterial processes, from expression of virulence, antibiotic and antifungal production, motility control, biofilm stability, control plasmid copy number and transfer, etc. AHLs are sensitive to both biotic and abiotic degradation, two features that likely play a crucial role in the physiology and ecology of bacteria, including modulation of virulence. This observation prompted the development of environmentally friendly procedures targeting QS regulation to reduce or suppress the aggressiveness of plant pathogens, e.g., Pectobacterium spp. This paper reviews several aspects of the above described phenomena.