PhD Microbial Ecology, University of New South Wales (Australia), 2007
Current Position: Assistant Professor, Dept. of Biological Sciences, University of Alberta (Edmonton)
Rebecca Case is a microbial ecologist studying the effects of bacterial-algal interactions on the marine sulfur cycle and on climate change more broadly.
Rebecca received her PhD in microbial ecology in January 2007 from the University of New South Wales, Australia. She also received a BA in environmental studies and a BSc in environmental science from UNSW. As part of her doctoral work at the university's Centre of Marine Biofouling and Bioinnovation, Rebecca isolated the bacterium, Ruegeria R11, a novel bacterial pathogen of algae whose virulence is temperature dependent, similar to the bacterial-induced bleaching of corals. Her finding suggests that algae may be susceptible to a similar impact from rising ocean temperatures via global warming as is seen in corals.
As an Environmental Fellow, Rebecca worked with Roberto Kolter of Harvard Medical School to continue her research on bacterial-algal interactions and unravel the role of this type of interaction in the release of the climate regulating compound dimethyl sulfide (DMS) from algae. The taxonomic group to which R11 belongs, roseobacters, are known to metabolize algal-derived dimethylsulfoniopropionate (DMSP) to DMS, an important intermediate in the sulfur cycle that regulates climate through formation of cloud condensation nuclei (CCN). CCN and the resulting cloud formation have a cooling effect on local temperatures. Thus, an important implication of this research is the potential negative feedback effect that this type of bacterial-algal interaction may produce as ocean temperatures rise. Increasing roseobacterial virulence, leading to the release of more algal-derived DMS and increased cloud formation, could potentially result in a self-regulating mechanism for climate.
Roberto Kolter, Harvard Medical School