Tzeng S F, Wolfe R S, Bryant M P
J Bacteriol. 1975 Jan;121(1):184-91. doi: 10.1128/jb.121.1.184-191.1975.
Methanobacterium ruminantium was shown to possess a nicotinamide adenine dinucleotide phosphate (NADP)-linked factor 420 (F420)-dependent hydrogenase system. This system was also shown to be present in Methanobacterium strain MOH. The hydrogenase system of M. ruminantium also links directly to F420, flavin adenine dinucleotide (FAD), flavin mononucleotide (FMN), methyl viologen, and Fe-3 plus. It has a pH optimum of about 8 and an apparent Km for F420 of about 5 x 10-6 M at pH 8 when NADP is the electron acceptor. The F420-NADP oxidoreductase activity is inactive toward nicotinamide adenine dinucleotide (nad) and no NADPH:NAD or FADH2(FMNH2):NAD transhydrogenase system was detected. Neither crude ferredoxin nor boiled crude extract of Clostridium pasteuranum could replace F420 in the NADP-linked hydrogenase reaction of M. ruminantium. Also, neitther F420 nor a curde "ferredoxin" fraction from M. ruminantium extracts could substitute for ferredoxin in the pyruvate-ferredoxin oxidoreductase reaction of C. pasteurianum.
已证明反刍甲烷杆菌拥有一种与烟酰胺腺嘌呤二核苷酸磷酸（NADP）相连的4黄素腺嘌呤二核苷酸（F420）依赖性氢化酶系统。该系统也存在于甲烷杆菌MOH菌株中。反刍甲烷杆菌的氢化酶系统还直接与F420、黄素腺嘌呤二核苷酸（FAD）、黄素单核苷酸（FMN）、甲基紫精和Fe3+相连。当NADP作为电子受体时，其最适pH约为8，在pH 8时F420的表观Km约为5×10-6M。F420-NADP氧化还原酶活性对烟酰胺腺嘌呤二核苷酸（NAD）无活性，未检测到NADPH:NAD或FADH2（FMNH2）:NAD转氢酶系统。粗制铁氧化还原蛋白或巴氏芽孢梭菌的煮沸粗提取物均不能在反刍甲烷杆菌的NADP连接的氢化酶反应中替代F420。此外，反刍甲烷杆菌提取物中的F420或粗制“铁氧化还原蛋白”组分均不能在巴氏芽孢梭菌的丙酮酸-铁氧化还原蛋白氧化还原酶反应中替代铁氧化还原蛋白。
