Michael J. Plewa

Research

My research program is focused in the areas of genetic toxicology and molecular mutagenesis. The current research projects in my laboratory are listed below.

Isolation and characterization of plant-activated arylamines: We published the first conclusive evidence that plants could metabolically convert non-mutagenic chemicals into mutagens that could induce genetic damage in consuming organisms. The plant activation of aromatic amines employs plant peroxidases and results in the generation of high molecular weight products (>100 kDa) that can inflict DNA damage in microbial and mammalian cells. The plant kingdom may be a reservoir for environmental contaminants which may be recycled into the biosphere. If even a small amount of plant-mediated contaminant recycling occurs then the environmental burden of chemical pollutants may be vastly underestimated.

Genotoxic synergy between organophosphorus ester insecticides and environmental and dietary aromatic amines: Genotoxic synergy is the interaction of two or more agents that causes an increase in DNA damage greater than the sum of their individual genotoxic effects. We discovered that organophosphorus ester insecticides and several environmental and dietary carcinogenic aromatic amines interact synergistically to generate an enhanced mutagenic response in Salmonella typhimurium and enhanced DNA damage in human lymphocytes. This enhanced genotoxic phenomenon associated with agents that are global environmental contaminants raises concerns about their impact upon the public health, especially for farmers, agricultural workers and residents of rural areas.

Isolation of novel antimutagens and anticarcinogens from agricultural products and by-products; analysis of the repression of growth rates of human tumor cell lines by agronomic processing waste fractions: We are isolating and chemically characterizing antimutagens and human tumor cell growth repressing agents from commercial processing wastes or by-products of corn and soybean. We developed mammalian cell methods to measure the repression of aromatic amine-induced DNA damage by very small amounts of complex mixtures, fractions or individual chemicals isolated from agricultural by-products. We integrate our analytical biological assays with separation and analytical chemistry conducted at the USDA laboratory at Peoria, IL. This research may lead to the isolation of novel chemoprotectants from agronomic commercial processing products and by-products.

Assessment of genotoxicity of disinfection by-products (DBPs) in drinking water generated from different disinfection processes: We calibrated and compared genotoxicity assays using transgenic mammalian cells and traditional bacterial assays to better assess the genotoxic risks associated with drinking water disinfection by-products (DBPs) and DBP mixtures. Our data derived from S. typhimurium provide a link to the literature while mammalian cell data provide an endpoint more relevant to the human condition. The U.S. EPA DBP occurrence data base is being used to direct the selection of agents for genotoxicity testing and to define the impact upon current water disinfection practice.

Teaching

• Crop Sciences 336 (ENVS 336, CHLH 336), Tomorrow's Environment.
  
• Crop Sciences 432 (ENVS 432), Fundamentals of Genetic Toxicology and Molecular Mutagenesis.
  
• Crop Sciences 433 (FSHN 480, Basic Toxicology (team taught).
  [Lecture Notes]
• Campus Honors Program 395, Controversial Environmental Issues: A Critical Thinking Approach.

• Member of the ACES Academy of Teaching Excellence.
  
• Member of the ACES Honors Council.
  
• Recipient of the Broadrick-Allen Award for Excellence in Honors Teaching.
  
• Recipient of the University of Illinois Campus Award for Excellence in Guiding Undergraduate Research.
  
• Named 12 times to the University of Illinois Incomplete List of Teachers Rated as Excellent by Their Students.

Professional Experience

Other Appointments

• Member, Gene-Tox Commission (Committee on Plant Systems), U.S. Environmental Protection Agency, Washington DC, 1980-1982.
  
• Visiting Scientist, Biology Division, Molecular Biology Program, Oak Ridge National Laboratory, Oak Ridge, TN, 1984-1985.
  
• Research Geneticist, Experimental Carcinogenesis and Mutagenesis Branch National Institute for Environmental Health Sciences, Research Triangle Park, NC. 1992-1993.
  
• J. William Fulbright Senior Scholar, Prague, Czech Republic, 1992-1993.
  
• Corresponding Scientist: U.S.-Czech Science and Technology Program. Office of International Cooperation and Development, U.S. Department of Agriculture 1993-1996; Academy of the Czech
• Republic, Visiting Scientist 1991, 1992, 1993, 1994, 1995, 1996, 1998, 2000.
  
• Visiting Scientist at BIBRA International (Great Britain) 1995, 1996, 1997, 1998, 1999.
  
• Kyoto University Scholar, Faculty of Engineering, Ministry of Education, Kyoto University, Japan, 1997, 1999, 2001.
  

Education

Select Publications

• Plewa, M.J., D.L. Weaver, L.C. Blair and J.M. Gentile. 1983. The activation of 2-aminofluorene by cultured plant cells. Science 219:1427-1429.
• Schy, W.E., and M.J. Plewa. 1989. Molecular dosimetry studies of forward mutation induced at the yg2 locus in maize by ethyl methanesulfonate. Mutation Research 211:231-241.
• Wagner, E.D., J.M. Gentile, and M.J. Plewa. 1989. Effect of specific monooxygenase and oxidase inhibitors on the activation of 2-aminofluorene by plant cells. Mutation Research 216:163-178.
• Schy, W.E., and M.J. Plewa. 1989. Use of the diaminobenzoic acid fluorescence assay in conjunction with UV absorbency as a means of quantifying and ascertaining the purity of a DNA preparation. Analytical Biochemistry 180:314-318.
• Wagner, E.D., M.M. Verdier and M.J. Plewa. 1990. The biochemical mechanisms of the plant activation of promutagenic aromatic amines. Environmental and Molecular Mutagenesis 15:236-244.
• Plewa, M.J. and E.D. Wagner. 1993. Activation of promutagens by green plants. Annual Review of Genetics 27:93-113.
• Gichner, T., J. Velemínský, E.D. Wagner and M.J. Plewa. 1996. Mutagenic synergy between paraoxon and plant-activated m-phenylenediamine or 2-acetoxyacetylaminofluorene. Environmental and Molecular Mutagenesis 27:59-66.
• Wagner, E.D., K. Repetny, J. Tan, T. Gichner and M.J. Plewa. 1997. Genotoxic synergy between paraoxon and mammalian or plant-activated arylamines. Environmental and Molecular Mutagenesis 30:312-320.
• Plewa, M.J., E.D. Wagner, L. Kirchoff, K. Repetny, L.C. Adams and A.L. Rayburn. 1998. The use of the Comet assay and flow cytometry to isolate antimutagens from commercial soybean products and by-products. Mutation Research 402:211-218.
• Wagner, E.D., A.L. Rayburn, D. Anderson and M.J. Plewa. 1998. Analysis of mutagens with single cell gel electrophoresis, flow cytometry, and forward mutation in an isolated clone of Chinese hamster ovary cells. Environmental and Molecular Mutagenesis 32:360-368.
• Plewa, M.J., E.D. Wagner, M.A. Berhow, A. Conway, A.L. Rayburn and D. Anderson. 1999. Antimutagenic activity of chemical fractions isolated from a commercial soybean processing by-product. Teratogenesis, Carcinogenesis, and Mutagenesis 19:121-135.
• Gichner, T., O. Ptá ek, D.A. Stavreva and M.J. Plewa. 1999. Comparison of DNA damage in plants as measured by single cell gel electrophoresis and somatic leaf mutations induced by monofunctional alkylating agents. Environmental and Molecular Mutagenesis 33:279-286.
• Kargalioglu, Y., B.J. McMillan, R.A. Minear and M.J. Plewa. 2000. A new assessment of the cytotoxicity and genotoxicity of drinking water disinfection by-products. In S.E. Barrett, S.W. Krasner and G.L. Amy (eds.) Natural Organic Matter and Disinfection By-Products: Characterization and Control in Drinking Water. ACS Symposium Series 761. American Chemical Society, Washington, 425 pp (pages 16-27).
• Berhow, M.A., E.D. Wagner, S.F. Vaughn, and M.J. Plewa. 2000. Characterization and antimutagenic activity of soybean saponins. Mutation Research 448:11-22.
• Plewa, M.J., Y. Kargalioglu, D. Vankerk, R.A. Minear and E.D. Wagner. 2000. Development of quantitative comparative cytotoxicity and genotoxicity assays for environmental hazardous chemicals. Water Science and Technology 42:109-116.
• Plewa, M.J., M.A. Berhow, S.F. Vaughn, E.J. Woods, M.S. Rundell, K. Naschansky, S. Bartolini and E.D. Wagner. 2001. Isolating antimutagenic components and cancer cell growth suppressors from agricultural by-products. Mutation Research 480-481:109-120.
• Kargalioglu, Y., B.J. McMillan, R.A. Minear and M.J. Plewa. 2002. An analysis of the cytotoxicity and mutagenicity of drinking water disinfection by-products in Salmonella typhimurium. Teratogenesis, Carcinogenesis, and Mutagenesis 22:113-128

Recent Publications

• Cemeli E., E.D. Wagner, D. Anderson, S. Richardson and M.J. Plewa. 2006. Modulation of the cytotoxicity and genotoxicity of the DBP iodoacetic acid by suppressors of oxidative stress. Environmental Science and Technology 40:1878-1883.
• Muellner, M.G., E.D. Wagner, K. McCalla, S. Richardson, Y-T. Woo and M. J. Plewa. 2007. Haloacetonitriles versus regulated haloacetic acids: Are nitrogen containing DBPs more toxic?  Environmental Science and Technology. 41:645-651.
• Attene-Ramos, M.S., E.D. Wagner, M.J. Plewa and H.R. Gaskins. 2006. Evidence that hydrogen sulfide is a genotoxic agent. Molecular Cancer Research 4:9-14.
• Stork, L.G., C. Gennings, W.H. Carter Jr., R.E. Johnson, D.P. Mays, J.E. Simmons, E.D. Wagner and M.J. Plewa. 2007. Testing for additivity in chemical mixtures using a fixed-ratio ray design and statistical equivalence testing methods. Agricultural, Biological, and Environmental Statistics. IN PRESS.
• Yeatts, S.D., C. Gennings, E.D. Wagner, J.E. Simmons, and M.J. Plewa. 2007. Detecting departure from additivity along a fixed-ratio ray with a piecewise model for dose and interaction thresholds. SUBMITTED TO EPA FOR REVEIW.
• Richardson, S.D., F.G. Cumley, J.J. Ellington, J.J. Evans, B.C. Blout, L.K. Silva, F.L. Cardinali, E.D. Wagner and M.J. Plewa. 2007. Occurrence and toxicity of iodo-acid and iodo-THM DBPs in chloraminated drinking water. Proceedings of the 2006 Carolina Environmental Program Symposium: Safe Drinking Water: Where Science Meets Policy, D. Crawford-Brown, J. Hughes and P. Singer (Eds). IN PRESS.
• Weber, D.F., M.J. Plewa and R. Feazel. 2007. Effect of B chromosomes on induced and spontaneous mutation frequencies in maize. Maydica IN PRESS.
• Daniel, S.L., G.L. Hartman, E.D. Wagner and M.J. Plewa. 2007. Assessing the toxicity of soybean rust fungicides using a mammalian cell cytotoxicity assay. Bulletin of Environmental Contamination and Toxicology. IN PRESS.
• Attene-Ramos M.S., E.D. Wagner, H.R. Gaskins and M.J. Plewa. 2007. Hydrogen sulfide induces direct radical associated DNA damage. Molecular Cancer Research 5:455-459.
• Plewa, M.J., M. Muellner, Susan Richardson, Y-T Woo, A.B. McKague, E.D. Wagner. 2007. Occurrence, chemical characterization and comparative mammalian cell toxicity of haloacetamide drinking water disinfection byproducts. SUBMITTED.
• Richardson, S.D., M.J. Plewa, E.D. Wagner., D.C. Wolf, R. Schoeny, and D.M. DeMarini. 2007. Occurrence, Genotoxicity, and Carcinogenicity of Emerging Disinfection By-products in Drinking Water:  A Review and Roadmap for Research. Mutation Research, ACCEPTED.
• Plewa, M.J., E.D. Wagner, M.G. Muellner, K-M Hsu, S.D. Richardon. 2007. Comparative Mammalian Cell Toxicity of N-DBPs and C-DBPs. In T. Karanfil, S.W. Krasner, P. Westerhoff, Y. Xie Eds., Occurrence, Formation, Health Effects and Control of Disinfection By-Products In Drinking Water, American Chem. Soc., Publication ACCEPTED.