Collaborative Research: The impact of ocean warming on bioactive trace metal requirements and use efficiencies of marine nitrifying microorganisms

This project seeks to provide a deeper understanding of how major biogeochemical cycles that support all living marine resources will respond to climate warming in a changing ocean environment. It will train one postdoctoral researcher and three graduate students, and provides research training opportunities for undergraduate students in microbial physiology and ecology, bioinformatics, trace metal biogeochemistry, and oceanography. Project personnel also conduct K-12 education and outreach activities. All data is freely available through the Biological and Chemical Oceanographic Data Management Office (BCO-DMO). This project investigates how climate warming will interact with the unique trace metal requirements of marine nitrifying microorganisms (nitrifiers) to affect ammonia and nitrite oxidation pathways in the rapidly changing ocean. Four investigators with diverse expertise in microbial global change physiology, nitrogen and trace metal biogeochemistry, and mechanistic transcriptomics and proteomics combine their efforts, using well-controlled pure culture-based laboratory studies along with field incubation experiments with natural communities to systematically investigate 1) thermal effects on iron (Fe) and copper (Cu) requirements and use efficiencies in isolated cultures and natural populations of marine ammonia-oxidizing archaea and bacteria (AOA, AOB) and nitrite-oxidizing bacteria (NOB), 2) the underlying molecular and biochemical mechanisms that facilitate such thermally-driven adaptive responses, and 3) system-level feedbacks between global change, trace metal biogeochemistry, and marine nitrifiers and their associated microbial communities in diverse marine environments. Together, these studies enhance our understanding of the marine nitrogen cycle and trace metal biogeochemistry, and ultimately contribute to a more detailed understanding of the impact of rapid ocean warming on critical major nutrient and micronutrient cycles. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.