Abstract: An investigation was conducted to identify electron transport carriers that participated the oxidation of H₂ in bacteroids of Rhizobium arachis.H₂-reduced mi-nus O₂-oxidized absorption difference spectra in bacteroids showed peaks at 424,500,520,550,560,585 and 595 nm,indicating the involvement of c-,b-,a and o-types of cytochromes,The absorption peaks at 520,550,560 nm were diminished a lot in the pres-ence of CN^- This showed that some of c- and b-type cytochromes were CN^- sensitive and therefore might play a role as terminal oxidases in H₂ metabolism. H₂-uptake was in-hibited by antimycin A,HONO,CN^-,N₃^- and DBMIB,not by rotenose,Our resultsindicate that ubiquinone and some types of cytochromes are involved in the oxyhydro-gen reaction which is a complex,branched transport system.

Key words: Peanut nodules, Bacteroid, H₂-oxidizing system

摘要： 花生根瘤菌类菌体含有吸H₂酶,以O₂或亚甲蓝为电子受体均表现吸H₂活性。类菌体还原减氧化的吸收差示光谱在424、500、520、550、560、585及595 nm处呈现吸收峰,表明细胞色素c、b、和o参与H₂的氧化过程。CN-明显影响520、550、560 nm处的吸收峰,意味着有些细胞色素c和b对CN^-敏感,在H₂代谢中充当末端氧化酶的作用。抗霉素A、HONO、CN^-、N₃^-和DBMIB均强烈抑制吸H₂活性,但鱼藤酮不抑制吸H₂活性。说明细胞色素b、c、a和泛配参与H₂氧化的电子传递,而NADH脱氢酶不参与。花生根瘤菌类菌体的H₂氧化系统是个复杂具分支的电子传递体系。

关键词: 花生根瘤, 类菌体, H₂氧化体系