My lab is focused on gaining a better understanding of the biogeochemical role of globally significant microorganisms that shape marine and terrestrial nutrient transformations, the ecological principles and environmental controls that govern their distribution, activity, and interaction in natural and engineered ecosystems, and the molecular and metabolic mechanisms that underpin their adaptations and stress responses to anthropogenic perturbations and global climate change processes.  Our current model microorganisms are nitrifying prokaryotes (i.e. nitrifiers), including Ammonia-oxidizing Archaea (AOA), Ammonia-oxidizing Bacteria (AOB), Complete Ammonia oxidizer (Comammox), and Nitrite-oxidizing Bacteria (NOB), which collectively drive the oxidation of reduced forms of nitrogen to nitrate and provide essential links in the nitrogen cycle of natural and engineered systems.  My lab aims to combine culture-based lab work and meta-omics-based field study to characterize the novel physiological and metabolic adaptive features that support the ecological succuss of these globally abundant nitrifiers, the metabolic and signaling interaction between nitrifiers and other associated biota, and the impact of anthropogenic perturbation and global climate-related changes on nitrifying microbial community dynamics and nutrient cycling in various ecosystems.