We study the interdependence of microbial activity and geochemical cycling in a range of environments.  The goal is to gain insight on defining the role of microbes in different environments - how much they affect the stability and transport of a variety of compounds in those environments.  Germaine topics addressing these questions include the kinetics of redox reactions such as the oxidation of pyrite, elemental sulfur, and ferrous iron, molecular clusters and reactions driving nanoparticle formation and dissolution, relating microbial ecology to geochemical niches, and the application of thermodynamic, kinetic, and molecular models to predictive analysis of environmental perturbation.

This research is complimented by the development and application of new methods for analyzing redox chemistry and nanoparticulate materials associated with microbial activity.  The application of in situ redox sensors and new techniques for chromatographic identification and quantification of redox species, molecular clusters, and nanoparticles is also of particular interest.