Commentary on Traditional and Modern Biomedical Prospecting: Part II—The Benefits by Werner E.G. Müller, Heinz C. Schröder, Matthias Wiens, Sanja Perović-Ottstadt, Renato Batel and Isabel M. Müller

This commentary continues to focus on the two papers cited in the editorial and naturally also alludes to other papers as we continue to emphasize the value of molecules derived from terrestrial and marine species for CAM (1–8). In recent years, marine natural product bioprospecting has yielded a considerable number of drug candidates (9). Most of these molecules are still in preclinical or early clinical development but some are already in the market, such as cytarabine, and it is predicted that some, such as ET743 (Yondelis), will be approved in near future. The ecology of marine natural products reveals that many of these compounds are chemical weapons and have evolved into highly potent inhibitors of physiological processes in the prey, predators or competitors of the marine organisms that utilize them for survival. Certain natural products isolated from marine invertebrates have been shown to be, or are suspected to be, of microbial origin; this is now thought to be the case for a majority of such molecules. Marine microorganisms, whose immense genetic and biochemical diversity is only beginning to be appreciated, may become a rich source of novel chemical entities for discovering more effective drugs. According to Donia and Hamann (10), oceans are unique resources that provide a diverse array of natural products, primarily from invertebrates such as sponges, tunicates, bryozoans and molluscs as well as from marine bacteria and cyanobacteria. Since infectious diseases evolve and develop resistance to existing pharmaceuticals, the marine environment provides novel leads against fungal, parasitic, bacterial and viral diseases. Several marine natural products, including dolastatin 10, ecteinascidin-743, kahalalide F and aplidine, have successfully advanced to late stages of clinical trials, and a growing number of candidates have been selected as promising leads for extended preclinical assessment (11). Although many marine-product clinical trials have been conducted for cancer chemotherapy, factors such as drug resistance, emerging infectious diseases and the threat of bioterrorism, have contributed to the interest for assessing natural ocean products in treating infectious and parasitic diseases.