Bioactive compounds from marine bacteria

Speaker: Professor Lone Gram, Department of Systems Biology, DTU
Host: Head of Department Niels Kroer, Department of Biology

Abstract
Oceanic environments cover 70% of our planet and make up 95% of the biosphere. They are home to many different life forms and it is believed that secondary metabolites produced by marine organisms hold great potential as novel compounds (drugs, enzymes, pigments) for the biotech and pharma industry. We established a collection of culturable, potentially bioactive marine bacteria during the Galathea 3 expedition in 2006-2007. We have isolated a range of known and novel antibacterial compounds from these bacteria, identified as Pseudoalteromonas and Vibrionaceae or belonging to the Roseobacter clade. Most of the Roseobacter-clade isolates were identified as Ruegeria mobilis and we have compared their genomes to unravel any geo-specificity or potential for production of novel bioactive compounds. Analyzing the genomes of Pseudoalteromonas and Vibrionaceae revealed a high (genetic) potential for secondary metabolite production and un-locking these potentially silent gene clusters is a challenge. A combination of chemical and transcriptomic analyses have shown that manipulating substrate, e.g. using natural substrates, such as chitin, is a way to influence production of secondary metabolites in marine bacteria. Overall, our findings do demonstrate a high bioactivity potential in marine bacteria.