Microorganisms have dominated the history of Earth, playing an intimate role in shaping its chemical and physical properties. Microbes continue their role as agents of biogeochemistry today as they drive a wide range of processes, including the cycling of carbon, oxygen, nitrogen, sulfur, and metals. My research interests are focused on this interplay between the biosphere and the geosphere, examining how microbes drive geochemistry and how geochemistry in turn shapes microbial diversity, metabolism, and evolution. Many biogeochemical cycles are actively driven by genetically encoded molecules that are often carefully regulated to be produced only under certain environmental or physiological conditions. Thus an understanding of biogeochemical cycles that take place on global scales demands knowledge of dynamics that take place on molecular scales. As such, my research relies heavily on molecular-biological approaches that are closely coupled with geochemical approaches to achieve an integrated view of geomicrobiology. (more)
Approaches and technical interests
- Genomics (metagenomics) and proteomics of microbial communities in natural environments; functional approaches for identifying genes and enzymes
- Biochemistry: protein purification and enzyme function
- Microbial physiology: isolation and physiological studies of microbes in pure culture
GEOSCI 112: Life in Extreme Enivronments (1 credit minicourse)
Life inhabits nearly every enivornment on Earth, from boiling hot springs to the bottom of the ocean to freezing subglacial lakes. This course surveys the bizarre life forms that call these environments home, explores adaptations to extreme physical and chemical conditions, and highlights biotechnological resources from extreme life.
GEOSCI/ENVIRON 175: The Microbial World (4 credits)
This course examines how microorganisms shape the world around us, both throughout the Earth's history and today. Major topics include the origin and evolution of life, the interplay between microbes and the enivornment, roles of microbes in global warming, and applications of microbiology in biotechnology and energy. Intended for non-science majors. Offered every winter.
GEOSCI 313: Geobiology (3 credits)
This course will address several core geobiological themes in two very different worlds, the microbial world and the vertebrate world. Themes included the coevolution of the biosphere and geosphere, major evolutionary innovations and events, diversity of life and metabolism, biomechanics, and biogeography.
GEOSCI 513: Microbial Biogeochemistry (2 credits)
This course investigates how and why microorganisms (primarily bacteria and archaea) drive geochemical processes. Emphasis is placed on the integration of cellular physiology/metabolism with cycling and transformation of elements. Topics include biomineralization, mineral dissolution and weathering, and critical evaluation of molecular biogeochemical approaches.