John Bumpus
Professor
Department of Chemistry
University of Northern Iowa
Cedar Falls, IA 50614-0423

Office: McCollum Science Hall, room 2250
Voice: (319) 273-7220
Email: John.Bumpus@uni.edu

Degrees

Research Interests
My research focuses on harnessing the unique biodegradative abilities of the wood-rotting fungus Phanerochaete chrysosporium for a variety of applications including bioremediation of contaminated soil and water. Lignin and cellulose are structural components of wood that are responsible for its durability and suitability as a building material. One of the characteristics of wood that make it suitable for such purposes is that the Iignin component is relatively resistant to attack and decay by microorganisms. Furthermore, it is thought that lignin also protects cellulose from microbial decay. Lignin, a non-repeating heteropolymer, is the second most abundant renewable carbon compound on earth. Only cellulose is more abundant. This, combined with the fact that only a relatively few microorganisms have the ability to degrade lignin, makes its turnover the rate-limiting step in the carbon cycle. Although lignin is clearly resistant to microbial decay, certain fungi are able to degrade lignin to carbon dioxide. Many such fungi belong to the Class Basidiomycotina. Of these, P. chrysosporium has been shown to mediate extensive degradation of lignin. In addition to its ability to degrade environmentally persistent naturally occurring compounds it has been shown that P. chrysosporium is also able to mediate extensive degradation of some of the most environmentally persistent synthetic organic pollutants known. Chlorinated compounds degraded to carbon dioxide by this fungus include polychlorinated biphenyls, chlorinated dioxins, the wood preservative pentachlorophenol and the insecticides DDT and chlordane. Chlorinated anilines which are metabolites of a number of pesticides are also degraded to carbon dioxide by this fungus. Many polycyclic aromatic hydrocarbons, including benzo[a]pyrene and phenanthrene are degraded by P. chrysosporium as are the explosives 2,4,6-trinitrotoluene and RDX. A number of studies have shown that the ability of P. chrysosporium to degrade such a wide variety of organic pollutants is due, at least in part, to its lignin degrading system which is expressed when fungal cultures become limited in nutrient nitrogen and/or carbon.

Selected Publications:
Introducing light scattering technology into the undergraduate curriculum, J. Chem.Ed. 2000 77:1396-1400.

Bioremediation of soil contaminated with explosives at the Naval Weapons Station Yorktown, Soil and Sediment Contamination 2000 9(6):537-548.

'Inactivation of Coprinus cinerus Peroxidase by 4-Chloroaniline During Turnover: Comparison with Horseradish Peroxidase and Lactoperoxidase, Chemico-Biological Interactions, 1999, 123:197-217.

Remediation of Water Contaminated with an Azo Dye: An Undergraduate Laboratory Experiment Utilizing an Inexpensive Photocatalytic Reactor, J. Chem. Ed.,1999, 76:1680-1683.

Biomimetic Solubilization of a Low Rank Coal: Implications for its use in Methane Production, Energy and Fuels,1998, 12:664-671.

Further Studies on the Inactivation by Sodium Azide of Lignin Peroxidase from Phanerochaete chrysosporium Archives of Biochemistry and Biophysics,1997, 338:200-209.

'Biodegradation of Congo Red by Phanerochaete chrysosporium -A Research Note,, Water Research, 1998, 32:1713-1717.

Microbial Degradation of Azo Dyes, Progress in Industrial Microbiology 1995, 32:157-176.

'Biodegradation of 2,4,6-Trinitrotoluene (TNT) by Phanerochaete chrysosporium : Identification of Initial Degradation Products and the Discovery of a TNT Metabolite that lnhibits Lignin Peroxidases', Current Microbiology 1994, 28:185-190.

'Biodegradation of Phenanthrene by Phanerochaete chrysosporium : On the Role of Lignin Peroxidase', Letters in Applied Microbiology1993, 17:20-24.

'Fungal Degradation of Organophosphorous Insecticides', J. Applied Biochemistry and Biotechnology 1993, 39-40: 715-726.

'Biodegradation of DDE (1,1-Dichloro-2,2-Bis(4-Chlorophenyl)Ethene by Phanerochaete chrysosporium', Mycological Research 1993, 97:95-98.

'Comparative Biodegradation of Alkyl Halide Insecticides by the White Rot Fungus Phanerochaete chrysosporium,' Applied and Environmental Microbiology 1990, 56:2347-2353.

'Biodegradation of TNT (2,4,6-Trinitrotoluene) by Phanerochaete chrysosporium'. Applied and Environmental Microbiology 1990, 56:1666-1671.

'Biodegradation of Azo and Heterocyclic Dyes by Phanerochaete chrysosporium', Applied and Environmental Microbiology 1990, 56:1114-1118.

'Oxidation of Persistent Environmental Pollutants by a White Rot Fungus,' Science 1985, 228: 1434-1436.