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The oxidase test is a test used in microbiology to determine if a bacterium produces certain cytochrome c oxidases.〔(【引用サイトリンク】title=Oxidase Test and Modified Oxidase Test )〕 It uses disks impregnated with a reagent such as ''N,N,N′,N′''-tetramethyl-''p''-phenylenediamine (TMPD) or ''N,N''-dimethyl-''p''-phenylenediamine (DMPD), which is also a redox indicator. The reagent is a dark-blue to maroon color when oxidized, and colorless when reduced. Oxidase-positive bacteria possess cytochrome oxidase or indophenol oxidase (an iron-containing hemoprotein).〔. Isenberg HD, editor. Clinical Microbiology Procedures Handbook. American Society for Microbiology; 2004. p. 3.3.2-3.3.2.13〕 These both catalyze the transport of electrons from donor compounds (NADH) to electron acceptors (usually oxygen). The test reagent, TMPD dihydrochloride acts as an artificial electron donor for the enzyme oxidase. The oxidized reagent forms the colored compound indophenol blue. The cytochrome system is usually only present in aerobic organisms that are capable of using oxygen as the terminal electron acceptor. The end-product of this metabolism is either water or hydrogen peroxide (broken down by catalase).〔MacFaddin JF, editor. Biochemical Tests for Identification of Medical Bacteria. 3rd ed. Philadelphia:Lippincott Williams and Wilkins; 2000. p. 363-7〕 ==Classification== Strains may be either oxidase-positive (OX+) or oxidase-negative (OX-). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Oxidase test」の詳細全文を読む スポンサード リンク
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