Biofilm formation and inhibition mediated by bacterial quorum sensing

As a complex microbial aggregate, biofilm is a group behavior of bacterial ability to adapt to the environment. Bacteria produce biofilm substrates that enhance their tolerance to stress and cause microbial infections. Biofilm infection is usually closely related to virulence, pathogenicity, and even life-threatening to immunocompromised patients. Therefore, studying bacterial biofilm generation and regulatory mechanisms has become one of the most important fields. It is well known that biofilm formation involves group behavior and relies on complex regulation of quorum sensing (QS). A series of small molecule compounds such as indole, AI-2 (autoinducer-2), AHL (N-acyl-homoserine lactone), AIP (auto-inducing peptide), and DSF (diffusible signal factor) are widely available intraspecific or interspecific signaling molecules, with regulatory functions on a wide range of physiological activities of bacteria, including biofilm formation. Given that various bacteria employ QS mechanisms to regulate biofilm formation, inhibition of QS becomes a promising potential strategy for the treatment of bacterial infections. Here, we describe how bacterial intraspecific and interspecific signaling molecules regulate the mechanism of biofilm formation and dispersion. This may contribute to anti-biofilm active molecules and provide ideas or directions for studies on controlling bacterial infections by inhibiting biofilm formation through QS. KEY POINTS: • The formation and hazard of biofilm have been discussed. • The effects of quorum sensing on biofilm formation have been highlighted. • The inhibition of biofilm through quorum sensing has been discussed and highlighted.