Ship Rusting in the Water

The Coates Lab also works on biotransformation of toxic and radioactive metals. 

Bacteria can transform various metals including radioactive and toxic metals such as uranium or chromium from a soluble form into an insoluble form.  As such these metals can be removed from contaminated water supplies and immobilized either in-situ or ex-situ, no longer posing a threat to the environment.

Over the last fifteen years the Coates Lab has concentrated on microorganisms that oxidize and precipitate metals out of solution in the absence of oxygen. This metabolism was identified less than 20 years ago and its true environmental importance is only now being recognized.  However, very little is known of the organisms responsible for this metabolism.  My research has focused on identifying the ubiquity and diversity of organisms capable of this metabolism, identifying the genes and biochemistry involved, and on the application of this metabolism for the precipitation and permanent immobilization of radioactive metals such as uranium or cobalt form drinking water supplies.

To this end we have isolated and described several novel bacteria from water and sediment systems contaminated with uranium.  We have demonstrated that the stimulated activity of these organisms can remove toxic metals from solution.  In the case of uranium we observed a reduction of almost 80% of the soluble content within one week.  More recently we have focused on identifying the underlying genetics and biochemistry of this metabolism, and the environmental conditions required for it to occur.  By performing comparative genomics, proteomics, and metabolomics were able to develop the first mechanistic model for how and why these organisms oxidize metals.  We are currently focused on determining the conserved nature of this model in microorganisms across the tree of life and on identifying any specific biomarkers that can be used as monitoring tools and predictive models of activity.  We are also focused on optimizing the application of this technology to a broad host of industrial processes with the aim of improving productivity with a minimized environmental footprint.