The objective of this project is to further characterize the biodegradation of environmental pollutant by white rot fungi. The proposed experiments reflect some recent findings that are extremely important with respect to the mechanism of degradation and consequently the design of degradation systems. These factors must be appreciated and understood in order to realize the potential of this biodegradation system. How these factors are involved in the mineralization of most environmental pollutants became obvious when we realized that many chemicals may require some reductive steps before oxidation can occur. Secondly, we realized the importance of these factors when we discovered how reduction might occur. Many environmental pollutants are already highly oxidized. For example, the highly chlorinated chemicals like the chlorinated solvents, DDT and PCB, can be considered highly oxidized because they are highly chlorinated. They are therefore difficult to oxidize until they are reduced. Reduction will involve dechlorination, then oxidation can occur. We now know how to catalyze reductions using an electron donor and a free radical mediator (veratryl alcohol).
The specific aims of the proposed research therefore are: 1. To determine the concentration of electron donors during the degradation of chemicals in cultures of P. chrysosporium. 2. To determine the concentration of veratryl alcohol or other free radical mediators during degradation of chemicals in cultures of P. chrysosporium. 3. To determine if the concentration of electron donors or free radical mediators are related to the extent of biodegradation. 4. To determine the effect of electron acceptor on the mineralization of chemicals by P. chrysosporium. 5. To determine if P. chrysosporium can mineralize some highly oxidized chemicals. 6. To develop and study a liquid bioreactor for treatment of contaminated water.

Project Start
Project End
Budget Start
Budget End
Support Year
6
Fiscal Year
1994
Total Cost
Indirect Cost
Name
Utah State University
Department
Type
DUNS #
City
Logan
State
UT
Country
United States
Zip Code
84322
Kwon, S I; Anderson, A J (2001) Catalase activities of Phanerochaete chrysosporium are not coordinately produced with ligninolytic metabolism: catalases from a white-rot fungus. Curr Microbiol 42:8-11
Tatarko, M; Bumpus, J A (1997) Further studies on the inactivation by sodium azide of lignin peroxidase from Phanerochaete chrysosporium. Arch Biochem Biophys 339:200-9
Nie, G; Aust, S D (1997) Effect of calcium on the reversible thermal inactivation of lignin peroxidase. Arch Biochem Biophys 337:225-31
Sutherland, G R; Zapanta, L S; Tien, M et al. (1997) Role of calcium in maintaining the heme environment of manganese peroxidase. Biochemistry 36:3654-62
He, B; Sinclair, R; Copeland, B R et al. (1996) The structure-function relationship and reduction potentials of high oxidation states of myoglobin and peroxidase. Biochemistry 35:2413-20
Goodwin, D C; Aust, S D; Grover, T A (1996) Free radicals produced during the oxidation of hydrazines by hypochlorous acid. Chem Res Toxicol 9:1333-9
Whitwam, R; Tien, M (1996) Heterologous expression and reconstitution of fungal Mn peroxidase. Arch Biochem Biophys 333:439-46
Khindaria, A; Yamazaki, I; Aust, S D (1996) Stabilization of the veratryl alcohol cation radical by lignin peroxidase. Biochemistry 35:6418-24
Khindaria, A; Aust, S D (1996) EPR detection and characterization of lignin peroxidase porphyrin pi-cation radical. Biochemistry 35:13107-11
Koduri, R S; Whitwam, R E; Barr, D et al. (1996) Oxidation of 1,2,4,5-tetramethoxybenzene by lignin peroxidase of Phanerochaete chrysosporium. Arch Biochem Biophys 326:261-5

Showing the most recent 10 out of 83 publications