The student will work jointly between the labs of Drs. Frank Stewart (Biological Sciences) and Kostas Konstantinidis (Biological Sciences, Civil and Environmental Engineering) to characterize a globally important marine bacterial group (SAR11). A collaboration between these labs recently described how SAR11, the world’s most abundant organismal group, has adapted to the unique chemical and physical environment of anoxic oxygen minimum zones (OMZs). This work (Tsementzi et al.
Single-celled marine algae are especially chemically rich, producing toxins that kill fish, marine mammals, and seabirds, contaminate shellfish, and threaten human health. Many predators of these algae – copepods – selectively consume less toxic algae, which in turn sense copepods via an excreted blend of copepod-specific molecules. These algae then become up to 20X more toxic when they sense copepod cues in the open ocean.
The urbanization of the coast is generating significant environmental issues, including increasing nutrient runoff that promotes eutrophication and hypoxic conditions in estuaries. At the same time, the excessive input of nutrients is also responsible for an increase acidification of coastal waters, as denitrification in sediments typically generates acidity.
Seaweeds create toxic compounds to deter consumers (fish) and poison competitors (corals). However specific fishes resist these toxins, and some corals also are resistant to their effects. These tolerances may be due to unusual microbes in the gut microbiomes of fishes and in coral mucus coverings. GT has an unusual mixture of marine ecologists, chemists and microbiologists to address these issues.
