Microbial transformation of metals
Research in my laboratory is focused on the microbial ecology of the interactions of microbes with toxic metals. Specifically, we are looking at microbial transformations of metals and how they affect metal toxicity and accumulation patterns in the environment and at the genetics and physiology of metal resistance and transformations in bacteria. This research supports efforts in bioremediation of metal contaminated environments. One on-going research projects is focused on the role of microbes in the formation and accumulation of methylmercury in aquatic environments. Methylmercury is the most toxic form of mercury that is accumulated and biomagnified in fish and shellfish posing a risk to predators (including humans) that rely on the aquatic food chain for sustenance. A second project examines the role of horizontal gene transfer among bacteria on the spread of mercury and antibiotics resistance genes. Such genetic spread might lead to the formation of antibiotics resistance gene pools in mercury-contaminated environments. Our research relies heavily on the application of molecular tools, such as cloning, gene probing, mRNA transcript analysis, metagenomics, and metatranscriptomics, in microbial ecology.
Lu, X., Y, Liu, A. Johs, L. Zhao, T. Wang, Z. Yang, H. Lin, D.A. Elias, E.M. Pierce, L. Liang, T. Barkay, and B. Gu. 2016. Anaerobic mercury methylation and demethylation by Geobacter bemidjensisBem. Environ. Sci. Technol. 50:4366-4373.
Janssen, S., M.W. Johnson, J.D. Blum, T. Barkay, and J.R. Reinfelder. 2015. Separation of monomethylmercury from estuarine sediments for mercury isotope analysis. Chem. Geol. 411:19-25
Møller, A.K., T. Barkay, M.A. Hansen, A. Norman, L. H. Hansen, S.J. Sørensen, E.B. Boyd and N. Kroer. 2014. Mercuric reductase genes (merA) and mercury resistance plasmids in High Arctic snow, freshwater, and sea-ice brine. FEMS Microbiol. Ecol. 87:52-63
Yu, R.-Q, J. Reinfelder, M. Hines, and T. Barkay. 2013. Mercury methylation by the methanogen Methanospirillum hungatei. Appl. Environ. Microbiol. 79:6325-6330. doi: 10.1128/AEM.01556-13
Poulain, A.J., and T. Barkay. 2013. Cracking the mercury methylation code. Science 339:1280-1281. doi: 10.1126/science.1235591