Microscopic marine algae (phytoplankton) are responsible for much of Earth’s photosynthesis, serving as the base of massive oceanic food webs supporting fisheries. Phytoplankton compete for limiting resources, with some species producing noxious compounds that kill competitors or inhibit their growth, a process termed “allelopathy.” The red-tide dinoflagellate Karenia brevis is one such allelopathic species, suppressing growth of other phytoplankton and negatively impacting coastal ecosystems. Cultures of K. brevis grown together with the robust model competitor, Asterionellopsis glacialis, caused little change in the metabolic profile of A. glacialis, however, when grown with the more sensitive model competitor isolated from the North Atlantic Ocean (separate from K. brevis), Thalassiosira pseudonana, detectable chemical changes in the metabolic profile of T. pseudonana were observed. A. glacialis was isolated from the Gulf of Mexico where K. brevis is naturally found, while T. pseudonana was isolated from the North Atlantic Ocean which is geographically isolated from K. brevis, allowing for an interesting comparison between species that could have naturally evolved resistance to K. brevis and one which could not have.
Current research goals are to identify compounds that notably change in concentration as a response to the presence of K. brevis in T. pseudonana to help us better understand the metabolic responses to competition and their consequences on bloom formation/propagation in phytoplankton communities.