Rosenberg Institute Seminar Series - Bradley B. Tolar

Bradley B. Tolar, Assistant Professor, Department of Biology and Marine Biology
University of North Carolina Wilmington

Combining Field- and Laboratory-Based Analyses to Characterize how Ammonia-Oxidizing Archaea Respond to Changing Conditions

Abstract
Ammonia-oxidizing archaea (AOA) are among the most abundant organisms on Earth and play a key role in the nitrogen cycle, oxidizing ammonia to nitrite as the first step in nitrification. These AOA are especially important in mediating nutrient cycling within estuaries and coastal oceans – both dynamic, high-flux systems. Many studies suggest that AOA abundance and activity are impacted by temperature, pH, salinity, and light availability. However, information on their physiology and metabolism are limited to a few isolates and experiments. Here we leverage long-term field monitoring with laboratory culture experiments to characterize AOA responses to environmental change. This includes investigating annual AOA blooms along the southeastern US that triggers decoupling of nitrification, compared to classifying the stress response of Nitrosarchaeum limnium via expressed transcripts and proteins. Together these studies improve our understanding of this important archaeal group, and support efforts to address the many unclassified genes and proteins they possess.

Bio
Dr. Bradley Tolar grew up on the Gulf of Mexico, which inspired his love for marine and environmental science. Through college and graduate school, he became a microbiologist trained in oceanography, developing a keen interest in how microorganisms interact with and adapt to changes in their environment, whether seasonal or sudden. His lab at UNC Wilmington focuses on Archaea in aquatic systems and within invertebrate hosts, and how they impact nitrogen cycling especially along the coast. Apart from research, Dr. Tolar is passionate about teaching, mentorship, and the cultivation of a more inclusive and supportive environment for all scientists.