Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.10.3.2 (laccase)
 4,656 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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.
 ...
PMID:Induction of hydroxyl radical production in Trametes versicolor to degrade recalcitrant chlorinated hydrocarbons. 1961 36

Advanced oxidation of benzene, toluene, ethylbenzene, and o-, m-, and p-xylene (BTEX) by the extracellular hydroxyl radicals (*OH) generated by the white-rot fungus Trametes versicolor is for the first time demonstrated. The production of *OH was induced by incubating the fungus with 2,6-dimethoxy-1,4-benzoquinone (DBQ) and Fe3+-EDTA. Under these conditions, *OH were generated through DBQ redox cycling catalyzed by quinone reductase and laccase. The capability of T. versicolor growing in malt extract medium to produce *OH by this mechanism was shown during primary and secondary metabolism, and was quantitatively modulated by the replacement of EDTA by oxalate and Mn2+ addition to DBQ incubations. Oxidation of BTEX was observed only under *OH induction conditions. *OH involvement was inferred from the high correlation observed between the rates at which they were produced under different DBQ redox cycling conditions and those of benzene removal, and the production of phenol as a typical hydroxylation product of *OH attack on benzene. All the BTEX compounds (500 microM) were oxidized at a similar rate, reaching an average of 71% degradation in 6 h samples. After this time oxidation stopped due to O2 depletion in the closed vials used in the incubations.
 ...
PMID:Advanced oxidation of benzene, toluene, ethylbenzene and xylene isomers (BTEX) by Trametes versicolor. 2062 9