>> Research Interests

I was once told that bacteria are everywhere and that they have been on Earth for a very long time. Fine.... but why study them in a geological context? Well, bacteria can be very active in the environment. We know for instance, that they are involved in various oxidation and reduction reactions. They can also act as reactive surfaces in sorption reactions and they can nucleate various minerals. If minerals can form on bacterial cells, how different are these minerals from abiotic ones and how important are they in the environment? Can they be used as biosignatures? In addition, how do anaerobic bacteria survive under stressful conditions such as those existing in mining environments? How do they cope with low pH and high redox conditions and how do they participate in Fe, S and C cycling? These are some of the questions my research team is working on.

>> Current Research Projects

• Microbial diversity of anaerobic bacteria in Cu-Zn mine tailings deposits in the Timmins area (Ontario). The study focuses on the diversity and functions of sulfate- and iron reducing bacteria and on their role in iron, sulfur and carbon cycling (NSERC).
• Redox stability of bacteriogenic iron oxides (BIOS): these minerals formed in close association with bacteria are very efficient at sorbing trace contaminants, but are they stable under reducing conditions? (Strategic NSERC project with Ian Clark (U of Ottawa )and Grant Ferris (U of Toronto)
• Can endostromatolites be used as "biosignatures" of past life? This project combines isotope geochemistry and molecular analyses (Canadian Space Agency)
• Iron and sulfur cycling in cold environments. (Antarctica). How does temperature affect microbial activity in permanently cold environments? Is phosphate (from animal droppings) affecting microbial activity in those environments? This project is in collaboration with Prof. Sun of USTC in China. (U of Ottawa)