Mohora M
Department of Biochemistry, Carol Davila University of Medicine and Pharmacy, 8 Eroilor Sanitari Str., 76243 Bucharest, Romania.
Rom J Intern Med. 2000;38-39:33-50.
This paper is a brief overview of current knowledge about DT-diaphorase [NAD(P)H: Quinone Oxidoreductase, NQO], flavoprotein that catalyzes the obligatory two-electron reduction of a wide variety of substrates. The most efficient substrates are quinones but the enzyme will also reduce quinone-imines, nitro and azo compounds. NQO is unique among known NAD(P)H-oxidizing flavoproteins in being a 2-electron transferring quinone reductase, and play a major role in preventing one-electron reduction of exogenous quinones by other enzymes to auto-oxidable semiquinones and concomitant superoxide-radical generation. Induction of NQO by a variety of xenobiotics (potential sources of free-radical formation which lead to DNA and cell damage) provides protection from the cytotoxic and carcinogenic effects of these compounds. NQO has an important role in the bioreductive activation of various quinones used in cancer chemotherapy.
本文简要概述了目前关于DT-黄递酶[NAD(P)H：醌氧化还原酶，NQO]的知识，NQO是一种黄素蛋白，可催化多种底物的强制性双电子还原反应。最有效的底物是醌类，但该酶也能还原醌亚胺、硝基和偶氮化合物。NQO在已知的NAD(P)H氧化黄素蛋白中独一无二，它是一种双电子转移醌还原酶，在防止其他酶将外源性醌单电子还原为可自动氧化的半醌以及伴随产生超氧自由基方面发挥着重要作用。多种异生物质（可能导致自由基形成并进而导致DNA和细胞损伤的潜在来源）对NQO的诱导作用可保护细胞免受这些化合物的细胞毒性和致癌作用。NQO在癌症化疗中使用的各种醌类的生物还原激活过程中具有重要作用。
