Marine ecosystems are characterized by tremendous biological diversity, fluctuating and often extreme abiotic conditions. To survive in this competitive and continuously changing environment, marine organisms evolved biosynthetic pathways that produce an array of compounds with unique chemical structures and potent biological activities.

Among those structures, there are various isoprenoids. Even though there is extensive research on isoprenoids from terrestrial organisms, marine counterparts have not received equal attention and the genetic and biochemical basis of their biosynthesis remains largely unexplored. Motivated both by the evolutionary interest and the biotechnological potential of marine isoprenoids, we aimed to elucidate the corresponding biosynthetic pathways in different algal species.

To this end, we used an integrated approach that combined RNA sequencing of algal samples with phylogenetic analysis and gene functional characterization and we elucidated critical steps of the pathway in the diatom Haslea ostrearia and in the red algae Laurencia obtusa.

Overall, this work provides a basis for in-depth understanding of how eukaryotic algal isoprenoids are built, covers the first steps towards unraveling the secrets of marine metabolic pathway evolution and paves the way for harnessing the biotechnological potential of novel marine molecules.