Research
Research in my laboratory is directed toward understanding the ecology of microorganisms and viruses in aquatic habitats. This work has taken me to the bottom of different great lakes using a submersible, to Russia and various oceans, but our current research efforts are focused on the North American Great Lakes and watersheds in northern Minnesota. Several graduate students and I are investigating the survival of exotic microorganisms in native microbial communities, the sources of Escherichia coli strains in watersheds, and the origins of archaeons in great lakes. There is great public concern about the quality of recreational waters and the safety of drinking water sources. We are determining the survival of pathogenic microbes in aquatic microbial communities. Recent work in our lab has demonstrated that suspended particles have very little effect on the survival of Salmonella typhimurium in freshwater. We are now examining if the pathogenic cells that survive in these microbial assemblages also express their invasive nature. Our newest project is identifying the animal origins of different strains of the water quality indicator bacterium, E. coli, which is found in the streams and nearshore areas of Lake Superior. With our colleagues, we plan to determine if the original sources of these strains are related to land use and if E. coli populations have become ‘naturalized’ members of aquatic habitats.
Another area of recent concentration for us is the search for the origins and ecological roles of archaeons in the plankton from great lakes of the world. Archaeons are procaryotic microorganisms similar to bacteria that have usually been isolated from extreme environments like hypersaline, hyperthermal, and strictly anoxic habitats. We have demonstrated that they are also present in small abundances within picoplankton communities from the waters of all great lakes that we have examined in North America, Russia and Africa. This finding suggests a cosmopolitan distribution of these Archaea in global freshwater environments but very little is known about their ecological roles in planktonic communities. The archaeal nucleic acids we have sequenced are most similar to those from non-thermophilic crenarchaeons in moderate marine and freshwater habitats. Members of this group are closely related to thermophilic archaeons found in hyperthermal environments, but so far they have not been isolated and cultured. We wish to learn more about the physiology and ecological roles of these archaeons. I encourage dedicated undergraduates and students wishing to pursue graduate degrees to join our research team and help us investigate the ecology of microbes in aquatic environments.
Recent Publications
Pundsack, J. W., R. E. Hicks , and R. P. Axler. 2005. Effect of alternative on-site wastewater treatment on the viability and culturability of Salmonella choleraesuis . J. Water and Health: in press.
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Pascoe, D. A., and R. E. Hicks . 2004. Genetic structure and community DNA similarity of picoplankton communities from the Laurentian great lakes. J. Great Lakes Res.: in press
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Hicks, R. E ., P. Aas, and C. Jankovich. 2004. Annual and offshore changes in bacterioplankton communities in the western arm of Lake Superior during 1989 and 1990. J. Great Lakes Res.: in press.
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Olson, M. R., R. P. Axler, and R. E. Hicks . 2004. Effects of freezing and storage temperature on MS2 viability. J. Virological Meth. 122:147-152.
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Keough, B., T. M. Schmidt, and R. E. Hicks . 2003. Archaeal nucleic acids in picoplankton from great lakes on three continents. Microbial Ecology 46:238-248.
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Maki, R. and R. E. Hicks . 2002. Salmonella typhimurium survival and viability is unaltered by suspended particles in freshwater. J. Environ. Qual. 31:1702-1709.
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Pascoe, D. A., and R. E. Hicks. Genetic structure and community DNA similarity of picoplankton communities from the Laurentian great lakes. Submitted to J. Great Lakes Res.
- Hicks, R. E., and D. A. Pascoe. 2001. A comparison of cyanobacterial dominance within the picoplankton of the North American Great Lakes estimated by 16S rRNA-based hybridizations and direct cell counts. Pp. 363-374 In Exploring the Great Lakes of the World: Food-web dynamics, health, & integrity, (Munawar, M. and R. Hecky, eds.) Backhuys Publishers b.v., Leiden, Netherlands
- Pundsack, J., R. Axler, R. Hicks, J. Henneck, D. Nordman, and B. McCarthy. 2001. Seasonal pathogen removal by alternative on-site wastewater treatment systems. Water Environ. Res. 73:204-212.
Teaches
- BIOL 1094. Northern Streams Ecosystems
- BIOL 5801. Microbial Ecology
- BIOL 5802. Microbial Ecology Lab
Graduate Student Projects
- Winfried Ksoll. In progress. Naturalization of Escherichia coli in the Sediments of Lake Superior and Factors Affecting their Survival Therein
- Wendy Hieb. In progress. Sources of Fecal Coliforms in Streams and Their Relationship to Land Use (tentative title). M.S. Thesis (Water Resources).
- Jennifer Schreiber. 2004. Expression of Virulence by Salmonella in Native Aquatic Microbial Communities (tentative title). M.S. Thesis (Biology).
- Matt Olson. 2004. Removal of Viruses from Wastewater by Alternative Treatment Systems (tentative title). M.S. Thesis (Biology).
- Brendan Keough. 2002. Archaeal Nucleic Acids in Picoplankton from Great Lakes of the World. M. S. Thesis (Biology).
Recent UROP student projects
Matt Kading. 2003-04. Determining Spatial Differences in Communities of Bacteria and Archaea.
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Matt Kading. 2002-03. Determining the Sources of Fecal Contamination Using Patterns in Antibiotic Resistance.
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Jessie Heimer. 2001-02. Identifying Sources of Escherichia coli by Metabolic Fingerprinting.
Family/Hobbies:
Spouse: Dr. Lucinda Johnson (Natural Resources Research Institute-UMD)
Hobbies: fly fishing, making bamboo fly rods, gardening, woodworking, canoeing
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