Mechanistic Insight into the Inhibitory Activity of Elasnin-Based Coating against Early Marine Biofilms

This study shows elasnin's possibilityin preventingmarine biofilm and biofouling and illustrates its mode of action asa signaling molecule. Marine biofilms are multispecies microbial communitieson surfacesthat are crucial to the marine environment. They cause marine corrosion,biofouling, and transmission of marine pathogens and thus pose a greatthreat to public health and the maritime industry. To control marinebiofilms, effective and environmentally friendly antibiofilm compoundsare highly needed. Elasnin is a potent antibiofilm compound that exhibitshigh efficiency in inhibiting marine biofilms and biofouling, butits mode of action remains unclear. In the present study, multiomicanalysis combined with quorum-sensing assays and in silico study revealed that elasnin acted as a signaling molecule in themicrobial community. Elasnin promoted the growth of dominant speciesin the biofilm but deprived their ability of sensing and respondingto environmental changes by disturbing their regulations of the two-componentsystem, i.e., the ATP-binding cassette transportsystem and the bacterial secretion system. Consequently, biofilm maturationand subsequent biofouler settlement were inhibited. Elasnin also exhibitedhigher antibiofilm efficiency than dichlorooctylisothiazolinone andhad low toxicity potential on the embryos and adults of marine medakafish. Overall, this study provided molecular and ecological insightsinto elasnin's mode of action, highlighting its applicationpotential in controlling marine biofilms and the feasibility and advantagesof using signal molecules to develop eco-friendly technologies.