Anti-quorum sensing activity of some marine bacteria isolated from different marine resources in Egypt

To screen for a variety of marine bacteria with anti-quorum sensing and anti-biofilm activities. Among 188 bacterial isolates from water, sediment, and corals in the Red Sea region, approximately 35% (65 isolates) of the isolates displayed a significant degradation in the purple pigment of the bioreporter strain without affecting cell growth. The quorum quenching bacteria obtained from coral-associated bacteria were 66.2% out of the total isolates. The PCR amplification results revealed that the recorded Acyl Homoserine lactone (AHL) inhibition by 91% of the anti-QS marine bacteria was not due to lactonase activity. On the other hand, lactonase genes were recorded only in the remaining 9% (6 isolates) and those were belonging to genus Bacillus, Nocardiopsis, and Enterobacter based on 16S rRNA gene sequences. The results also showed that marine bacteria with anti-QS activity inhibited 67% of the biofilm formed by Aeromonas hydrophila, Pseudomonas aeruginosa, and Vibrio alginolyticus. The computational profiling analysis confirmed the presence of the functional region in the detected genes. Coral microbial communities are rich sources for pharmacologically important natural products with anti-quorum sensing and anti-biofilm activities.