title: Acceleration of azo dye decolorization by using quinone reductase activity of azoreductase and quinone redox mediator.
abstract: This study demonstrated the effective application of intracellular azoreductase in mediated decolorization of azo dyes. Using the quinone reductase activity of overexpressed azoreductase AZR and quinone redox mediators, the decolorization performance of the recombinant strain Escherichia coli YB was significantly enhanced. In the presence of 0.2 mM lawsone, 75% acid red 27 (1 mM) was decolorized by E. coli YB in only 2 h, which was the highest bacterial decolorization rate ever reported. Compared to lawsone, menadione was a less effective redox mediator. Glucose was found to be the best carbon source for mediated decolorization by E. coli YB. The recombinant strain could complete four rounds of mediated decolorization repeatedly in 12 h. In addition, a 10-min pre-incubation of E. coli JM109 and activated sludge with 2-methylhydroquinone resulted in great improvement of mediated decolorization performance, which may be applied in practical treatment.
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Guangfei
authors.initials: G
authors.lastname: Liu
authors.forename: Jiti
authors.initials: J
authors.lastname: Zhou
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Mi
authors.initials: M
authors.lastname: Zhou
authors.forename: Hong
authors.initials: H
authors.lastname: Lu
authors.forename: Ruofei
authors.initials: R
authors.lastname: Jin
mesh_terms: D001391:Azo Compounds / Q000737:chemistry* / Q000378:metabolism*; D016227:Benzoquinones / Q000378:metabolism*; D003116:Color; D004789:Enzyme Activation; D004926:Escherichia coli / Q000145:classification / Q000201:enzymology*; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000378:metabolism*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism*; D009601:Nitroreductases; D010084:Oxidation-Reduction
chemical_list: D001391:Azo Compounds; D016227:Benzoquinones; C004532:quinone; D009247:NADH, NADPH Oxidoreductases; D016660:NAD(P)H Dehydrogenase (Quinone); D009601:Nitroreductases; C021106:azoreductase