Exploring the chemical diversity in marine organisms: new molecules for pharmaceutical applications

It is increasingly recognized that the oceans preserve a huge number of natural products and novel chemical entities, with biological activities that may be useful in the quest for finding drugs with greater efficacy and specificity for the treatment of many human diseases. In this light, the aim of my project was to isolate and characterize novel molecules from marine organisms with regard to the identification of new "lead compounds" for pharmaceutical applications. The organisms considered for this study were selected by using two different strategies. The first one was based on enhancement of the taxonomic diversity. In this process, an emphasis was placed on collecting specimens related to - but differing from - those known to contain bioactive natural products. The second approach was to evaluate ecological factors such as costumer pressure, growth form (e.g. thin encrusting), level of resource competition, presence or absence of biofouling, etc., and relate this to the expression of the secondary metabolism. Some invasive species have chemical defences, which may enhance their invasion success, so as many marine organisms are soft bodied and have a sedentary life style necessitating chemical means of defence. Therefore, they have evolved the ability to synthesize or to obtain from marine microorganisms bioactive compounds that help them in deterring predators, keep competitors at bay or paralyze their prey. [edited by the author]