Quorum sensing of Shewanella marisflavi influences biofilm formation and the settlement and metamorphosis of Mytilus coruscus

Abstract:

[Background] Biofilms as the main existing form of marine bacteria are related to the settlement and metamorphosis of marine invertebrates and regulated by quorum sensing, and thus it is of great significance to understand the relationship between quorum sensing, biofilm formation, and marine invertebrate metamorphosis. [Objective] To explore the relationship between quorum sensing, biofilm formation, and settlement and metamorphosis of Mytilus coruscus by adding quorum sensing inhibitors. [Methods] Different quorum sensing inhibitors (2-5H-furanone, 2-4-thiazolidinedione, pyrogallol, furanone C-30, and coumarin) were applied to Shewanella marisflavi, and the extracellular polymeric substance content of the biofilm was observed by confocal laser scanning microscopy (CLSM). With M. coruscus as the model, the effects of bacterial biofilms interfered by quorum sensing inhibitors on the settlement and metamorphosis of M. coruscus were studied. [Results] Quorum sensing inhibitors decreased the content of extracellular α-polysaccharide and protein in the biofilm of Shewanella. Furthermore, the post-larval rate of M. coruscus was decreased. [Conclusion] The quorum sensing system of S. marisflavi can regulate the extracellular polymeric substance content of the biofilm, thus indirectly influencing the settlement and metamorphosis of M. coruscus.