title: Induction of hydroxyl radical production in Trametes versicolor to degrade recalcitrant chlorinated hydrocarbons.
abstract: Extracellular hydroxyl radical ((*)OH) production via quinone redox cycling in Trametes versicolor, grown in a chemically defined medium, was investigated to degrade trichloroethylene (TCE), perchloroethylene (PCE), 1,2,4- and 1,3,5-trichlorobenzene (TCB). The activity of the enzymes catalyzing the quinone redox cycle, quinone reductase and laccase, as well as the rate of (*)OH production, estimated as the formation of thiobarbituric acid reactive substances (TBARS) from 2-deoxyribose, increased rapidly during the first 2-3 days and then remained at relatively constant levels. Under quinone redox cycling conditions, TCE degradation was concomitant to TBARS production and chloride release, reaching a plateau after 6 h of incubation. Similar results were obtained in PCE, 1,2,4- and 1,3,5-TCB time course degradation experiments. The mole balance of chloride release and 1,2,4-TCB and TCE degraded suggests that these chemicals were almost completely dechlorinated. Experiments using [(13)C]-TCE confirmed unequivocal transformation of TCE to (13)CO(2). These results are of particular interest because PCE and 1,3,5-TCB degradation in aerobic conditions has been rarely reported to date in bacterial or fungal systems.
authors.affiliation: Departament d'Enginyeria Química and Institut de Ciència i Tecnologia Ambiental, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain. ernest.marco@uab.es
authors.forename: Ernest
authors.initials: E
authors.lastname: Marco-Urrea
authors.forename: Elisabet
authors.initials: E
authors.lastname: Aranda
authors.forename: Gloria
authors.initials: G
authors.lastname: Caminal
authors.forename: Francisco
authors.initials: F
authors.lastname: Guillén
mesh_terms: D001673:Biodegradation, Environmental; D001709:Biotechnology / Q000379:methods*; D002713:Chlorine / Q000737:chemistry*; D002722:Chlorobenzenes / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006838:Hydrocarbons / Q000737:chemistry*; D017665:Hydroxyl Radical; D010084:Oxidation-Reduction; D013750:Tetrachloroethylene / Q000737:chemistry; D017392:Thiobarbituric Acid Reactive Substances; D013997:Time Factors; D055454:Trametes / Q000378:metabolism*; D014241:Trichloroethylene / Q000737:chemistry; D018508:Water Purification / Q000379:methods
chemical_list: D002722:Chlorobenzenes; D006838:Hydrocarbons; D017392:Thiobarbituric Acid Reactive Substances; C009947:1,2,4-trichlorobenzene; D014241:Trichloroethylene; C500273:1,3,5-trichlorobenzene; D017665:Hydroxyl Radical; D002713:Chlorine; D013750:Tetrachloroethylene