The Environmental Chemical Sciences Program in the Chemistry Division at the National Science Foundation supports the research of Professor Jean-Francois Gaillard at Northwestern University who seeks to establish the processes that control the bioavailability of Mercury (Hg) in aquatic systems and particularly to better delineate the role played by complexation reactions with human made ligands. Mercury biouptake by microbial species is a key step in the formation of methyl-mercury, one of the most potent neurotoxins known. Professor Gaillard will examine how bacterial surface processes regulate this process when the chemical speciation of Hg in solution is controlled by the presence of either anthropogenic or biogenic ligands. The interactions of Hg with cell binding sites will be investigated using spectroscopic and microscopic methods, whereas Hg biouptake will be assessed using a whole cell biosensor. Hg complexation reactions in solution will also be investigated using voltammetric methods. The goal of this research is to provide a molecular perspective on mercury biouptake as well as challenge conventional views on ligands controlled metal biouptake.
The exacerbation of the release of mercury to the global environment as a result of human activities such as coal burning has raised a general concern about this pollutant that is distributed worldwide. The proposed work has many essential connections to engineering applications and the protection of human and ecological health. It evaluates in both fundamental and practical ways the fate of Hg in response to anthropogenic releases and redefines Hg entry pathways into microbial foodwebs. This research program will train a Ph.D. and undergraduate students in environmental bioinorganic chemistry and develop collaborations with the industry that is working to control Hg concentrations in the environment.
