George Bullerjahn

Dr. George Bullerjahn

Emeritus Professor
Ph. D., University of Virginia

Office:     516 Life Sciences Building
Phone:   1-419-372-8527

Research: Microbial physiology; Cyanobacteria   

Great Lakes Center for Fresh Waters and Human Health



Research Interests:

Our work is currently focused on enumeration and the physiological performance of phototrophs and ecologically important chemolithotrophs in aquatic systems. Additionally, we examine the composition and dynamics of cyanobacterial and nitrifying communities in freshwater environments, focusing primarily on the N and P cycles in the Laurentian Great Lakes.  These studies assist in the assessment of factors contributing to toxic cyanobacterial bloom events in freshwaters.

Selected Publications

McKay, R.M.L., O. Prasil, L. Pechar, E. Lawrenz and G.S. Bullerjahn. 2015. Freshwater ice as habitat: partitioning of phytoplankton and bacteria between ice and water in central European reservoirs. Environ. Microbiol. Reports 7: 887-898.

Bullerjahn, G.S., R.M.L. McKay, T.W. Davis, D.B. Baker, G.L. Boyer, L.V. D’Anglada, G.J. Doucette, J.C. Ho, E.G. Irwin, C.L. Kling, R.M. Kudela, R. Kurmayer, A.M. Michalak, J.D. Ortiz, T.G. Otten, H.W. Paerl, B. Qin, B.L. Sohngen, R.P. Stumpf, P.M. Visser and S.W. Wilhelm. 2016. Global solutions for regional problems: collecting global expertise to address the problem of harmful algal blooms. - A Lake Erie case study. Harmful Algae 54: 223-238.

Small, G., S. Brovold, G.S. Bullerjahn, J.C. Finlay, R.M. McKay, M.J. Rozmarynowycz, K. Spokas and R.W. Sterner. 2016. Spatial heterogeneity in denitrification rates across the Laurentian Great Lakes. Biogeochemistry 128: 353-368.

Steffen, M.M., T.W. Davis, R.M. McKay, G.S. Bullerjahn, L.E. Krausfeldt, J.M.A. Stough, M.L. Neitzey, N.E. Gilbert, G.L. Boyer, T.H. Johengen, D.C. Gossiaux, A.M. Burtner, D. Palladino, M. Rowe, G.L. Dick, K. Meyer, S. Levy, B. Boone, R. Stumpf, T. Wynne, P.V. Zimba, D.B. Guttierez and S.W. Wilhelm. 2017. Ecophysiological examination of the Lake Erie Microcystis bloom in 2014: linkages between biology and the water supply shutdown of Toledo, Ohio. Environ. Sci. Technol. 51: 6745-6755.

Salk, K. R., G.S. Bullerjahn, R.M.L. McKay, J.D. Chaffin, and N.E. Ostrom. 2018. Nitrogen cycling in Sandusky Bay, Lake Erie: Oscillations between strong and weak export and implications for harmful algal blooms, Biogeosciences 15: 2891–2907.

Knackstedt, K.A., B.F. Moffett, S. Hartmann, H. Wex, T.C.J. Hill, E.D. Glasgo, L.A. Reitz, S. Augustin-Bauditz, B.F.N. Beall, G.S. Bullerjahn, J. Fröhlich-Nowoisky, S. Grawe, J. Lubitz, F. Stratmann and R.M.L. McKay. 2018. A terrestrial origin for abundant riverine nanoscale ice-nucleating particles. Environ. Sci. Technol. 52: 12358-12367.

Hampel, J., M.J. McCarthy, M. Neudeck, G.S. Bullerjahn, R.M. McKay and S.E. Newell. 2019. Ammonium recycling supports toxic Planktothrix blooms in Sandusky Bay, Lake Erie: evidence from stable isotope and metatranscriptome data. Harmful Algae 81: 42-52.

Davenport, E.J., M.J. Neudeck, P.G. Matson, G.S. Bullerjahn, T.W. Davis, S.W. Wilhelm, M.K. Denny, L.E. Krausfeldt, J.M.A. Stough, K.A. Meyer, G.J. Dick, T.H. Johengen, E. Lindquist, S.G. Tringe and R.M.L. McKay. 2019. Metatranscriptomic analyses of diel metabolic functions during a Microcystis bloom in western Lake Erie (USA). Frontiers Microbiol. 10: 2081.

Krausfeldt, L.E., M.M. Steffen, R.M. McKay, G.S. Bullerjahn, G.L. Boyer and S.W. Wilhelm. 2019. Metatranscriptome analyses suggest that mlr pathway is not a dominant route for microcystin degradation during Microcystis blooms in Lake Erie and Lake Tai. Frontiers Microbiol. 10: 2741.

Matson, P., G. Boyer, T. Bridgeman, G.S. Bullerjahn, D.D. Kane, R.M. McKay, K. McKindles, H. Raymond, B. Snyder, R. Stumpf and T.W. Davis. 2020. Physical drivers facilitating a toxigenic cyanobacterial bloom in a major Great Lakes tributary. Limnol. Oceanogr. 65: in press. doi: 10.1002/lno11558.

Wilhelm, S.W., G.S. Bullerjahn and R.M. McKay. 2020. The complicated and confusing ecology of Microcystis blooms. mBio 11: e00529-20.

Bullerjahn, G.S., R.M.L. McKay, G. Bernat, O. Prasil, L. Vörös, K. Palffy, N. Tugyi and B. Somogyi. 2020. Community dynamics and function of algae and bacteria during winter in central European great lakes. J. Great Lakes Res. 46: 732-740.

McKindles, K.M., M.A. Manes, J.R. DeMarco, A. McClure, R.M. McKay, T.W. Davis and G.S. Bullerjahn. 2020. Dissolved microcystin release linked to lysis of a Microcystis-dominated bloom in western Lake Erie attributed to a novel cyanophage. Appl. Environ. Microbiol. 86: in press.