City of Microbes: Untapped Diversity of Microbial Associants of Marine Invertebrates
Ocky Karna Radjasa, Department of Marine Science, Diponegoro University
Coral reefs are among the most productive marine ecosystems and are the sources of a large group of structurally unique natural products mainly accumulated in reef's invertebrates such as sponges, softcorals, tunicates, bryozoans and molluscs which have pronounced pharmacological activities. However, it is widely known that a serious obstacle to the ultimate development of most marine natural products from reef’s invertebrates is the problem of supply. Providing sufficient amounts of these biologically active substances, then may be a difficult task. Exploitation is further complicated by the fact that most of these metabolites possess highly complex structures, making them difficult to be produced economically via chemical synthesis. There is an urgent need to consider the bioethical aspects for anticipating the consequences and to find an alternative for sustainable use of reef's invertebrates as the sources of marine natural products.
Dealing with the bioprospecting of microbial symbionts of reef’s invertebrates such as sponges, corals, softcorals, tunicates, and nudibrach I screened these symbionts for the production of secondary metabolites in particular with significant contribution in the health sector. I’m interest in the molecular diversity of microbial symbionts as the source of antimicrobial including Multi Drugs Resistant (MDR) strains including MDR-TB. I also work on the new avenue of research on the exploration of caroteniod pigments by these microbial symbionts as the alternative sources of natural pigments with potential biological activity such as precursor vitamin A, and antioxidant. In collaboration with Indonesian partners, I also interested in exploring enzymes from microbial symbionts. In addition I apply molecular approaches through PCR-based screening for the presence of Non-Ribosomal Peptide Synthetase (NRPS) and Polyketide Synthase (PKS) both culturable and unculturable parts of microbial symbionts.
I am also interested in microbial community associated with healthy and diseased corals. In particular, the ecological role of these associants both in healthy and diseased corals.