Catherine Girard, Département de biochimie, de microbiologie et de bio-informatique
I earned my PhD at the Université de Montréal, where I studied the gastrointestinal microbiome of an Inuit population and its role in the metabolism of dietary mercury. During this time, I also completed a Fulbright fellowship at the University of Texas at Austin, focusing on the metabolism of insecticides by the honeybee microbiome, which broadened my perspective on the interactions between microbiomes, contaminants, and health. I then pursued a postdoctoral fellowship in viral ecology at Université Laval, where I investigated cryospheric viruses and their roles in extreme habitats. Afterwards, I was appointed assistant professor at UQAC, where I developed my research program on microbial connectivity in the Arctic, exploring how microorganisms and their genes disperse across glaciers, lakes, and soils. I am now an assistant professor in viral ecology in the Department of Biochemistry, Microbiology, and Bioinformatics at Université Laval. My current program focuses on viruses in cold habitats and their psychrophilic hosts, and on how they respond to climate change in the Arctic and the boreal regions.
My research program investigates how microorganisms from cold environments respond to climate change, with a particular focus on the cryosphere and northern freshwater ecosystems. These environments are undergoing rapid transformation, yet the microbial and viral communities that inhabit them remain largely unexplored. To address this gap, my team combines high-throughput omics approaches, advanced bioinformatic analyses, and detailed environmental monitoring to uncover the hidden diversity of these communities and to evaluate their functional roles. We pay special attention to psychrophiles, microorganisms adapted to thrive at low temperatures, which dominate microbial assemblages in Arctic and boreal regions. Our research particularly targets the microorganisms living in the ice and beneath the ice of northern lakes, where winter processes set the stage for ecosystem productivity throughout the year. We also investigate the ecological connectivity between glaciers and lakes, which structures the dispersion of microorganisms, genes, and viral particles across habitats. By tracing these connections, we aim to understand how microbial life and its interactions shape biogeochemical cycles, ecosystem resilience, and ultimately the ecosystem services that sustain northern communities. Through this integrated approach, my program advances knowledge of microbial and viral ecology in cold environments while providing new insights into the responses of northern ecosystems to a rapidly warming climate.