Sequencing of Algal Blooms Shows Tenacious Quality of Brown Tides

A comparison of phytoplankton genomes from harmful brown tides and other more benign marine algae show that the phytoplankton that causes brown tides has evolved into an organism perfectly suited to the over-fertilized, polluted, and low-light conditions common in coastal zones where the blooms occur. Studying the 56-million base pair sequence of the brown tide, Aureococcus anophagefferens, researchers from the State University of New York, Stony Brook, and the Woods Hole Oceanographic Institution determined that the algae had many advantages over its competitors. These include 62 light-harvesting genes, compared to less than half that number in other algae, enabling brown tide to thrive in low light conditions, as well as numerous genes that enable it to metabolize the high levels of nitrogen, carbon, and toxic metals found in polluted coastal areas. Brown tides have become increasingly common in coastal zones and these blooms have decimated sea grass beds and shellfisheries, leading to billions of dollars in economic losses. The study is published in the online edition of the Proceedings of the National Academy of Sciences.