嗜碱芽孢杆菌的NADH脱氢酶在存在来自木聚糖两栖芽孢杆菌的22 kDa蛋白质组分时的过氧化物还原酶活性。

Peroxide reductase activity of NADH dehydrogenase of an alkaliphilic Bacillus in the presence of a 22-kDa protein component from Amphibacillus xylanus.

作者信息

Koyama N, Koitabashi T, Niimura Y, Massey V

机构信息

Department of Chemistry, Faculty of Science, Chiba University, Japan.

出版信息

Biochem Biophys Res Commun. 1998 Jun 29;247(3):659-62. doi: 10.1006/bbrc.1998.8749.

DOI:10.1006/bbrc.1998.8749

PMID:9647749

Abstract

The NADH oxidase of Amphibacillus xylanus shows high NADH-peroxide reductase activity for hydrogen peroxide and alkyl hydroperoxides in the presence of a 22-kDa disulfide-containing protein component (Y. Niimura, L. B. Poole, and V. Massey, J. Biol.Chem. 270, 25645-25650, 1995). It was found that the membrane-bound NADH dehydrogenase of an alkaliphilic Bacillus (YN-1) involved in the respiratory chain also exhibits reductase activity for hydrogen peroxide and cumene hydroperoxide in the presence of the 22-kDa component from Amphibacillus xylanus. Vmax values for these substrates were as high as those of the NADH oxidase of A. xylanus. Although the 38-kDa protein produced by trypsin treatment of NADH dehydrogenase retains NADH dehydrogenase activity, it exhibited no peroxide reductase activity in the presence of the 22-kDa component from A. xylanus. The NADH dehydrogenase of YN-1 might not only catalyze electron flow from NADH to the respiratory chain, but also function for scavenging peroxide.

摘要

木聚糖两栖芽孢杆菌的NADH氧化酶在一种含22 kDa二硫键的蛋白质组分存在的情况下，对过氧化氢和烷基氢过氧化物表现出较高的NADH - 过氧化物还原酶活性（Y. Niimura、L. B. Poole和V. Massey，《生物化学杂志》270，25645 - 25650，1995年）。研究发现，参与呼吸链的嗜碱芽孢杆菌（YN - 1）的膜结合NADH脱氢酶在存在来自木聚糖两栖芽孢杆菌的22 kDa组分时，对过氧化氢和异丙苯过氧化氢也表现出还原酶活性。这些底物的Vmax值与木聚糖两栖芽孢杆菌的NADH氧化酶的Vmax值一样高。尽管用胰蛋白酶处理NADH脱氢酶产生的38 kDa蛋白质保留了NADH脱氢酶活性，但在存在来自木聚糖两栖芽孢杆菌的22 kDa组分时，它没有表现出过氧化物还原酶活性。YN - 1的NADH脱氢酶可能不仅催化电子从NADH流向呼吸链，还具有清除过氧化物的功能。