Ph. D., McGill University

   

Office:     424B Life Sciences Building

Phone:   1-419-372-6873

Email:    rmmckay@bgnet.bgsu.edu

   

Research:

Aquatic microbial ecology; Phytoplankton-trace metal interactions

   

Personal Research Page

   

 

   

Research Interests:

For decades, our ideas on nutrient availability in aquatic ecosystems have been informed largely by chemical measurement of dissolved elements. While this provides a reasonable proxy, it tells us little about the bioavailability of a given nutrient. Distinguishing between biologically available, and refractory forms of a nutrient has been cited as a particular challenge by the oceanographic community.

The availability of key nutrients could be better understood if a biological system were to be used to estimate nutrient supply. Promising in this regard is the use of genetically-altered organisms as biological reporter systems to assess the bioavailability of a chemical compound. The development and use of freshwater cyanobacterial bioreporters by our group to assess the availability of iron, phosphorus and nitrogen has been met with interest by aquatic scientists due to the ability of these tools to offer insight into the availability of an element from the perspective of an important member of the endemic phytoplankton community.

Future work in the lab will continue our development and characterization of luminescent cyanobacterial bioreporters to offer a rapid assessment of nutrient bioavailability from marine waters. Our recent success in developing a luminescent whole-cell cyanobacterial bioreporter for measuring Fe availability in diverse marine environments has provided important proof of concept. We are now ready to expand the use of bioreporters to the ocean milieu.

Selected Publications:

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, doi:10.1128/AEM.01670-06.

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.

Hassler, C.S., M.R. Twiss, R.M.L. McKay and G.S. Bullerjahn. 2006. Optimization of iron-dependent cyanobacterial (Synechococcus, Cyanophyceae) bioreporters to measure iron bioavailability. Journal of Phycology 42: 324-335.

McKay, R.M.L., S.W. Wilhelm, J. Hall, D.A. Hutchins, M.M.D. Al-Rshaidat, C.E. Mioni, S. Pickmere, D. Porta and P.W. Boyd. 2005. The impact of phytoplankton on the biogeochemical cycling of iron in subantarctic waters southeast of New Zealand during FeCycle. Global Biogeochemical Cycles 19, GB4S24, doi:10.1029/2005GB002482.

McKay, R.M.L., D. Porta, G.S. Bullerjahn, M.M.D. Al-Rshaidat, J.A. Klimowicz, R.W. Sterner, T.M. Smutka, E.T. Brown and R.M. Sherrell. 2005. Bioavailable iron in oligotrophic Lake Superior assessed using biological reporters. Journal of Plankton Research 27: 1033-1044, doi:10.1093/plankt/fbi070

Boyd, P.W., R. Strzepek, S. Takeda, G. Jackson, C.S. Wong, R.M. McKay, C. Law, H. Kiyosawa, H. Saito, N. Sherry, K. Johnson, J. Gower, and N. Ramaiah. 2005. The evolution and termination of an iron-induced mesoscale bloom in the northeast subarctic Pacific. Limnology and Oceanography 50: 1872-1885.

Ivanikova, N.V., R.M.L. McKay and G.S. Bullerjahn. 2005. Construction and characterization of a cyanobacterial bioreporter capable of assessing nitrate assimilatory capacity in freshwaters. Limnology and Oceanography: Methods 3: 86-93.

Boyd, P.W. and others. 2004. The decline and fate of an iron-induced subarctic phytoplankton bloom. Nature 428: 549 - 553; doi:10.1038/nature02437.

Sterner, R.W., T.M. Smutka, R.M.L. McKay, X. Qin, E.T. Brown and R.M. Sherrell. 2004. Phosphorus and trace metal limitation of algae and bacteria in Lake Superior. Limnology and Oceanography 49: 495-507.

Xia, L., A.F. Yakunin and R.M.L. McKay. 2004. The Fe-responsive accumulation of redox proteins ferredoxin and flavodoxin from a marine cryptomonad. European Journal of Phycology 39: 73-82.

Porta, D., G.S. Bullerjahn, K.A. Durham, S.W. Wilhelm, M.R. Twiss and R.M.L. McKay. 2003. Physiological characterization of a Synechococcus sp. (Cyanophyceae) strain PCC 7942 iron-dependent bioreporter for freshwater environments. Journal of Phycology 39: 64-73.

Boyd, P.W. and others. 2000. A mesoscale phytoplankton bloom in the polar Southern Ocean stimulated by iron fertilization. Nature 407: 695-702.

McKay, R.M.L., R.J. Geider and J. LaRoche. 1997. Physiological and biochemical response of the photosynthetic apparatus of two marine diatoms to Fe stress. Plant Physiology 114: 615-622.

LaRoche, J., P.W. Boyd, R.M.L. McKay and R.J. Geider. 1996. Flavodoxin as an in situ marker for iron stress in phytoplankton. Nature 382: 802-805.