Deinococcus radiodurans can interfere with quorum sensing by producing an AHL ‐acylase and an AHL ‐lactonase

Bacterial communication via the secretion of small diffusible compounds allows microorganisms to regulate gene expression in a coordinated manner. As many virulence traits are regulated in this fashion, disruption of chemical communication has been proposed as novel antimicrobial therapy. Quorum‐quenching enzymes have been a promising discovery in this field as they interfere with the communication of Gram‐negative bacteria. AHL ‐lactonases and AHL ‐acylases have been described in a variety of bacterial strains; however, usually only one of these two groups of enzymes has been described in a single species. We report here the presence of a member of each group of enzymes in the extremophile bacterium Deinococcus radiodurans . Co‐occurrence of both enzymes in a single species increases the chance of inactivating foreign AHL signals under different conditions. We demonstrate that both enzymes are able to degrade the quorum‐sensing molecules of various pathogens subsequently affecting virulence gene expression. These studies add the quorum‐quenching enzymes of D. radiodurans to the list of potent quorum‐quenchers and highlight the idea that quorum quenching could have evolved in some bacteria as a strategy to gain a competitive advantage by altering gene expression in other species.