Yagi T, Hon-nami K, Ohnishi T
Department of Basic and Clinical Research, Research Institute of Scripps Clinic, La Jolla, California 92037.
Biochemistry. 1988 Mar 22;27(6):2008-13. doi: 10.1021/bi00406a030.
Two types of the NADH-quinone reductase were isolated from Thermus thermophilus HB-8 membranes, by use of the nonionic detergent, dodecyl beta-maltoside, and NAD-agarose affinity, DEAE-cellulose, hydroxyapatite, and Superose 6 column chromatography. One of these (NADH dehydrogenase 1) is a complex composed of 10 unlike polypeptides, and the other (NADH dehydrogenase 2) exhibits a single band (Mr 53,000) upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The NADH-ubiquinone-1 reductase activity of the isolated NADH dehydrogenase 1 was about 14 times higher than that of the dodecyl beta-maltoside extract and partially rotenone sensitive. The NADH-ubiquinone-1 reductase activity of the isolated NADH dehydrogenase 2 was about 30-fold as high as that of the dodecyl beta-maltoside extract and rotenone insensitive. The purified NADH dehydrogenase 1 contained noncovalently bound FMN, non-heme iron, and acid-labile sulfide. The ratio of FMN to non-heme iron to acid-labile sulfide was 1:11-12:7-9. The high content of iron and labile sulfide is suggestive of the presence of several iron-sulfur clusters. The purified NADH dehydrogenase 2 contained noncovalently bound FAD and no non-heme iron or acid-labile sulfide. The activities of both NADH dehydrogenases were stable at temperatures of greater than or equal to 80 degrees C. The occurrence of two distinct types of NADH dehydrogenase as a common feature in the membranes of various aerobic bacteria is discussed.
通过使用非离子去污剂十二烷基β-麦芽糖苷以及NAD-琼脂糖亲和、DEAE-纤维素、羟基磷灰石和Superose 6柱色谱法，从嗜热栖热菌HB-8膜中分离出了两种类型的NADH-醌还原酶。其中一种（NADH脱氢酶1）是由10种不同多肽组成的复合物，另一种（NADH脱氢酶2）在十二烷基硫酸钠-聚丙烯酰胺凝胶电泳上呈现单一条带（Mr 53,000）。分离出的NADH脱氢酶1的NADH-泛醌-1还原酶活性比十二烷基β-麦芽糖苷提取物的活性高约14倍，且对鱼藤酮部分敏感。分离出的NADH脱氢酶2的NADH-泛醌-1还原酶活性比十二烷基β-麦芽糖苷提取物的活性高约30倍，且对鱼藤酮不敏感。纯化的NADH脱氢酶1含有非共价结合的FMN、非血红素铁和酸不稳定硫化物。FMN与非血红素铁与酸不稳定硫化物的比例为1:11 - 12:7 - 9。铁和不稳定硫化物的高含量表明存在几个铁硫簇。纯化的NADH脱氢酶2含有非共价结合的FAD，且不含非血红素铁或酸不稳定硫化物。两种NADH脱氢酶的活性在大于或等于80摄氏度的温度下稳定。本文讨论了两种不同类型的NADH脱氢酶作为各种需氧细菌膜的共同特征的存在情况。
