Our work is currently focused on the regulation of nutrient-stress-inducible genes in cyanobacteria. We have identified genes and gene products inducible under nutrient (N, S, P) limitation and stationary phase conditions, and this work has aided in the development of whole-cell biosensors detecting the bioavailability of nutrients in environmental samples. Secondly, we examine the composition and dynamics of cyanobacterial communities in aquatic systems. Third, we are examining the structural requirements for productive electron transport in photosynthesis by studying the protein-protein interactions occurring between the copper protein plastocyanin and its reaction partners (Photosystem I and cytochrome f).
We are also working on enumeration and the physiological performance of phototrophs and ecologically important chemolithotrophs in aquatic systems. We have identified genes and gene products inducible under nutrient (N, P) limitation and stationary phase conditions, and this work has aided in the development of whole-cell biosensors (bioreporters) detecting the bioavailability of nutrients in environmental samples. 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.
Kutovaya, O.A., R.M.L. McKay and G.S. Bullerjahn. 2013. Detection and expression of genes for phosphorus metabolism in picocyanobacteria from the Laurentian Great Lakes. Journal of Great Lakes Research 39: in press.
Small, G.E., G.S. Bullerjahn, R.W. Sterner, B.F.N. Beall, S. Brovold, J.C. Finlay, R.M.L. McKay and M. Mukherjee. 2013. Rates and controls on nitrification in a large oligotrophic lake. Limnology and Oceanography 58: 276-286.
D’souza N.A., Y. Kawarasaki, J.D. Gantz, R.E. Lee, B.F.N. Beall, Y.M. Shtarkman, Z.A. Kocer, S.O. Rogers, H. Wildschutte, G.S. Bullerjahn and R.M.L.McKay. 2013. Diatom assemblages promote ice formation in large lakes. ISME Journal 7: 1632-1640.
French, E., J. Kozlowski, M. Mukherjee, G. Bullerjahn and A. Bollmann. 2012. Niche differentiation between ammonia-oxidizing archaea and bacteria based on differences in their growth responses to environmental factors. Applied and Environmental Microbiology 78: 5773-5780.
Kutovaya, O.A. R.M.L. McKay, B.F.N. Beall, S.W. Wilhelm, D.D. Kane, J.D. Chaffin, T.B. Bridgeman and G.S. Bullerjahn. 2012. Evidence against fluvial seeding of recurrent toxic blooms of Microcystis spp. in Lake Erie's western basin. Harmful Algae 15: 71-77.
Ilikchyan, I.N., R.M.L. McKay, O.A. Kutovaya, R. Condon and G.S. Bullerjahn. 2010. Seasonal expression of the picocyanobacterial phosphonate transporter gene phnD in the Sargasso Sea. Frontiers in Microbiology 1: 135. doi:10.3389/fmicb.2010.00135.
Bullerjahn, G.S., R. Boyanpalli, M.J. Rozmarynowycz and R.M.L. McKay. 2010. Cyanobacterial bioreporters as sensors of nutrient availability. Advances in Biochemical Engineering/ Biotechnology 118: 165-188.
Ilikchyan, I.N., R.M.L. McKay, J.P. Zehr, S.T. Dyhrman and G.S. Bullerjahn. 2009. Detection and expression of the phosphonate transporter gene phnD in marine and freshwater picocyanobacteria. Environmental Microbiology 11: 1314-1324.
Sharma, A.K., K. Sommerfeld, G.S. Bullerjahn, A. Matteson, S.W. Wilhelm, J. Jezbera, U. Brandt, W.F. Doolittle and M.W. Hahn. 2009. Widespread distribution of actinorhodopsin genes in freshwater habitats and among diverse actinobacterial lineages. ISME Journal 3: 726-737.
Hulsker, R., M.V. Baranova, G.S. Bullerjahn and M. Ubbink. 2008. Dynamics in the transient Prochlorothrix hollandica plastocyanin-cytochrome f complex. Journal of the American Chemical Society 130: 1985-1991.
Ivanikova, N.V., R.M.L. McKay, G.S. Bullerjahn and R.W. Sterner. 2007. Nitrate utilization in Lake Superior is impaired by low nutrient (P, Fe) availability and seasonal light limitation a cyanobacterial bioreporter study. Journal of Phycology 43: 475-484.
Ivanikova, N.V., L. Popels, R.M.L. McKay and G.S. Bullerjahn. 2007. Lake Superior supports unique clusters of cyanobacterial picoplankton. Applied and Environmental Microbiology 73: 4055-4066.
Boyanapalli, R., G.S. Bullerjahn, C. Pohl, P.L. Croot, P.W. Boyd and R.M.L. McKay. 2007. Luminescent whole-cell cyanobacterial bioreporter for measuring Fe availability in diverse marine environments. Applied and Environmental Microbiology 73:1019-1024