Expression of a cDNA Encoding Rat Liver DT-Diaphorase in Escherichia Coli
Quinones and their precursors are widely distributed in nature, both as natural compounds and as environmental pollutants (Smith,1985). The toxicity and mutagenicity of quinones are believed to be due to their enzymatic one electron reduction by flavoenzymes to form semiquinones which can alkylates critical nucleophiles or generate superoxide anion radical through a redox cycling process (Thor et al., 1985; Chesis et al., 1984). DT-diaphorase (NAD(P)H: quinone oxidoreductase, EC 126.96.36.199.) is a unique flavoprotein in that it catalyzes the obligatory two electron reduction of quinones to hydroquinones via a pathway bypassing the formation of semiquinone; thus, playing a protective role against quinone toxicity (Ernster et al., 1986; Atallah et al., 1988).
KeywordsCell Free Extract HindIII Site Quinone Oxidoreductase Quinone Reductase Electron Reduction
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