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Kathleen  Scott

Kathleen Scott

Kathleen Scott
Associate Professor


Office: BSF 132
Phone: 813-974-5173
Lab: BSF 122, BSF 124
Fax: 974-3263



Ph.D. Biology, Penn State at University Park, 1998.
Post Doctoral Fellow, Harvard University.


Microbial physiology and biogeochemistry

Autotrophic microorganisms from all three domains of life (Bacteria, Archaea, and Eukarya) proliferate under a dizzying array of conditions. These organisms fix carbon dioxide while growing in more familiar habitats like lakes and oceans, but also thrive in extreme environments such as terrestrial hot springs, deep-sea hydrothermal vents and hydrocarbon seeps, acid rock drainage, and the subsurface biosphere.
Added to this breadth in habitats is a breadth in history. The three domains of life are believed to have originated rather early in Earth history, by 2.7 billion years ago. Since that time, the atmospheric concentration of carbon dioxide has fallen by nearly three orders of magnitude, while atmospheric oxygen, which inhibits some carbon fixing enzymes, has risen from nil to its current level of 21% by volume.

My major research question is, how have these organisms adapted to these changes? How do they fix carbon despite low concentrations of carbon dioxide, and elevated concentrations of oxygen? Have organisms within Bacteria and Archaea devised many different mechanisms for coping with these conditions, or did a few efficient methods (e.g., carbon concentrating mechanisms, carbonic anhydrases) originate fairly early on and are currently used by phylogenetically broad groups of organisms?
Given that many key autotrophic organisms are uncultivable, it is necessary for me to use a rather broad arsenal of methods to study them, including molecular tools and mass spectrometry. Elucidating the answers to the questions I raise above promises to have a substantial effect on our understanding of geochemical cycles and autotroph physiology, as well as their response to anthropogenic increases in atmospheric carbon dioxide.

Specialty Area

Microbial Physiology and Biogeochemistry