Molecular Interactions as Drivers of Changes in Marine Ecosystems

Abstract

Among the factors affecting community dynamics, bioactive natural products act as mediators of key biological processes, including competition, predation, defense, and reproduction. Their chemical diversity thus critically contributes to the stability of ecological systems. Accordingly, research in chemical ecology provides useful information for a better understanding of ecosystem functioning and biodiversity. On the other hand, the potential of bioactive molecules produced by invasive species to become disruptive to native communities has been recently emphasized in the literature, raising novel and urgent questions about the interactions of invasive metabolites with macromolecular counterparts of ecological and ecotoxicological interest. Relevant issues strongly emerged in the Mediterranean Sea where the green alga Caulerpa cylindracea and the seagrass Halophila stipulacea, both exotic macrophytes containing peculiar bioactive compounds, have become invasive. In particular, the study of these two species has led to the production of a recent literature focusing on "alien biomolecules" and their potential impact on the native community. The present article summarizes the obtained results by giving special emphasis to the urgent need for individuating molecular interactions that are likely to exert cascade effects at all levels of biological organization, from molecules to ecosystems.

An Alkaloid from a Highly Invasive Seaweed Increases the Voracity and Reproductive Output of a Model Fish Species

“…Its high palatability is consistent with a low level of the toxic and feeding-deterrent sesquiterpene caulerpenyne, which is instead abundant in the congeneric inedible Caulerpa taxifolia [ 5 ]. On the other hand, C. cylindracea contains much higher levels of the harmless bisindole alkaloid caulerpin (CAU) [ 3 ], exhibiting a panel of biological activities of interest in food science and pharmacology [ 6 , 7 ], including its action as an agonist of peroxisome proliferator-activated receptors (PPARs) [ 3 ]. According to relevant literature [ 8 , 9 , 10 , 11 , 12 ], this latter finding suggests a possible involvement of CAU in the regulation of fish metabolism, food intake, and reproductive function.…”