Life Sciences Commons^™

Metabolic Variability In Seafloor Brines Revealed By Carbon And Sulphur Dynamics, Samantha B. Joye, Vladimir A. Samarkin, Beth! N. Orcutt, Ian R. Macdonald, Kai-Uwe Hinrichs, Marcus Elvert, Andreas P. Teske, Karen Lloyd, Mark A. Lever, Joseph P. Montoya, Christof D. Meile

Karen Lloyd

Brine fluids that upwell from deep, hot reservoirs below the sea bed supply the sea floor with energy-rich substrates and nutrients that are used by diverse microbial ecosystems. Contemporary hypersaline environments formed by brine seeps may provide insights into the metabolism and distribution of microorganisms on the early Earth or on extraterrestrial bodies. Here we use geochemical and genetic analyses to characterize microbial community composition and metabolism in two seafloor brines in the Gulf of Mexico: an active mud volcano and a quiescent brine pool. Both brine environments are anoxic and hypersaline. However, rates of sulphate reduction and acetate production …