Detection of peroxisomal fatty acyl-coenzyme A oxidase activity.
Detection of peroxisomal fatty acyl-coenzyme A oxidase activity.
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DOI：
10.1042/bj1820779
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发表时间：
1979-09
期刊：
影响因子：
--
通讯作者：
N. Inestrosa;M. Bronfman;F. Leighton
中科院分区：
文献类型：
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作者：
N. Inestrosa;M. Bronfman;F. Leighton
据推测，过氧化物酶体脂肪酸氧化系统[Lazarow & de Duve（1976）Proc. Natl. Acad. Sci. U.S.A.73，2043- 2046; Lazarow（1978）J.Biol.Chem.253，1522- 1528]类似于线粒体，除了第一个氧化反应。在这个步骤中，O2将被氧化酶直接还原为H2 O2。两个具体的程序开发，以检测活性的特征酶脂肪酰辅酶A氧化酶，即极谱检测棕榈酰辅酶A依赖氰化物不敏感的O2消耗和棕榈酰辅酶A依赖H2 O2的产生耦合到过氧化的甲醇在抗霉素A不敏感的反应。脂肪酰基辅酶A氧化酶活性受FAD刺激，这支持了该酶的黄素蛋白性质。其活性每克湿重增加7倍。用降血脂药萘芬诺平治疗的大鼠的肝脏。正常和那非那平处理动物肝脏的亚细胞分级分离为其过氧化物酶体定位提供了证据。棕榈酰辅酶A依赖性O2消耗、H2 O2生成和NAD+还原的化学计量为1：1：1。这表明脂肪酰辅酶A氧化酶是过氧化物酶体脂肪酸氧化系统的限速酶。
It has been postulated that the peroxisomal fatty acid-oxidizing system [Lazarow & de Duve (1976) Proc. Natl. Acad. Sci. U.S.A. 73, 2043--2046; Lazarow (1978) J. Biol. Chem. 253, 1522--1528] resembles that of mitochondria, except for the first oxidative reaction. In this step, O2 would be directly reduced to H2O2 by an oxidase. Two specific procedures developed to detect the activity of the characteristic enzyme fatty acyl-CoA oxidase are presented, namely polarographic detection of palmitoyl-CoA-dependent cyanide-insensitive O2 consumption and palmitoyl-CoA-dependent H2O2 generation coupled to the peroxidation of methanol in an antimycin A-insensitive reaction. Fatty acyl-CoA oxidase activity is stimulated by FAD, which supports the flavoprotein nature postulated for this enzyme. Its activity increases 7-fold per g wet wt. of liver in rats treated with nafenopin, a hypolipidaemic drug. Subcellular fractionation of livers from normal and nafenopin-treated animals provides evidence for its peroxisomal localization. The stoicheiometry for palmitoyl-CoA-dependent O2 consumption, H2O2 generation and NAD+ reduction is 1 : 1 : 1. This suggests that fatty acyl-CoA oxidase is the rate-limiting enzyme of the peroxisomal fatty acid-oxidizing system.