Microbial Oceanography

Evidence from the research over last one decade have brought to light the complex and crucial role played by marine microbes in the food web, nutrient cycling, formation of Oxygen Minimum Zone (OMZ) etc. Marine microbes such as picoplankton, archae bacteria, actinomycetes, fungi and virus occupy all realms in ocean including bottom sediments, hydrothermal vents, polar ice caps etc. Their numerical abundance is much higher than all known marine species put together. These microbes may be free living or associated with other marine biota as commensals, symbionts, parasites and pages influencing the host physiology and metabolism in ways unknown to us. Microbial mediated bioluminescence and toxin secretions are reported from many marine organisms. Many microbes especially actinomycetes secrete specialized enzymes and antibiotics having therapeutic and pharmaceutical applications. Whereas, microbes such as cyanobacteria, clostridium etc., help in nitrogen fixation, the anaerobic bacteria associated with POM of the OMZ area causes denitrification and release of nitrous oxide - a green-house gas - as end product. The role of bacteria in the anamox reactions has also been recently reported. Viruses, besides being known pathogens, also causes senescence of micro algae, lysis of bacterial cells and the production of dimethyl sulphide (DMS) by enzymatic hydrolysis of Dimethyl Sulphonio Propionate (DMSP). The realization that the functional role of microbes in the marine environment are diverse and perhaps more significant than thought earlier, have led to the emergence of microbial oceanography as a specialized branch of marine sciences. However, one of the major challenges in this field is the problem that only few of these microbes are culturable in the laboratory conditions and therefore sophisticated tools such as metagenomics need to be applied to document the microbial diversity.

This program is aimed at filling the gap in knowledge on the mineral cycling that occurs in the Arabian Sea through microbial chain making use of advancements in scientific approach like proteomics, genomics and meta-genomics.