Marine microbial diversity and ecology: importance and future perspectives

The world ocean with a coastline of 312,000 km (193,000 miles) and a volume of 137 × 10 km, is the largest ecosystem on earth, and has been used for a variety of purposes by man for millennia. Because of its large volume and vast area, influence of the world ocean on world climate is profound. Microorganisms occur nearly everywhere in nature and occupy an important place in human view of life. Marine microbes represent a potential source for commercially important bioactive compounds and their bioremediation capabilities are also remarkable. They also play a crucial role in decomposition of organic matter and cycling of nutrients. Microbes also serve as food for some bottom-living organisms. Our knowledge of marine microbial diversity has, however, been severely limited by relying on microorganisms that have been cultured.