Alien biomolecules: a new challenge for natural product chemists

Among natural products there are molecules well known to influence the abundance and distribution of marine organisms and to play important roles in their interactions with one another. Recently, chemical ecologists have also started to consider how research on natural products might be useful in understanding marine biological invasions, assessing their impact in the invaded areas, and considering how to deal with them. Their efforts especially focused on the Mediterranean Sea, which is one of the major hotspots of marine biological invasions on earth, showing in what way marine natural products (MNPs) may influence (1) the ability of exotic marine organisms to invade and to get established, (2) how they affect the invaded biota, and (3) public health and the economy. In all cases, the study of such chemical warfare between alien and native species started with the isolation of the pure chemicals required for chemical structure elucidation and subsequent biological testing, implying a central role of natural product chemistry in approaching critical issues in invasion biology. In this position paper we also introduce a theme of possible interest for managing marine invasive species, based on the exploitation of available chemical and biological information on MNPs. We show how a kind of chemical data originally gathered for other objectives--such as obtaining drugs from the sea--might also offer valid alternatives to unrealistic eradication campaigns, becoming the basis for a desirable commercial use of the bioactive compounds obtainable from marine pests, thus paving the way for making the control of invasions profitable. The pests might then be harvested, reducing their impact on marine ecosystems.