Fauque G, Peck H D, Moura J J, Huynh B H, Berlier Y, DerVartanian D V, Teixeira M, Przybyla A E, Lespinat P A, Moura I
Section Enzymologie et Biochimie Bactérienne, ARBS, CEN Cadarache, Saint-Paul-Lez-Durance, France.
FEMS Microbiol Rev. 1988 Dec;4(4):299-344. doi: 10.1111/j.1574-6968.1988.tb02748.x.
Three types of hydrogenases have been isolated from the sulfate-reducing bacteria of the genus Desulfovibrio. They differ in their subunit and metal compositions, physico-chemical characteristics, amino acid sequences, immunological reactivities, gene structures and their catalytic properties. Broadly, the hydrogenases can be considered as 'iron only' hydrogenases and nickel-containing hydrogenases. The iron-sulfur-containing hydrogenase ([Fe] hydrogenase) contains two ferredoxin-type (4Fe-4S) clusters and an atypical iron-sulfur center believed to be involved in the activation of H2. The [Fe] hydrogenase has the highest specific activity in the evolution and consumption of hydrogen and in the proton-deuterium exchange reaction and this enzyme is the most sensitive to CO and NO2-. It is not present in all species of Desulfovibrio. The nickel-(iron-sulfur)-containing hydrogenases [( NiFe] hydrogenases) possess two (4Fe-4S) centers and one (3Fe-xS) cluster in addition to nickel and have been found in all species of Desulfovibrio so far investigated. The redox active nickel is ligated by at least two cysteinyl thiolate residues and the [NiFe] hydrogenases are particularly resistant to inhibitors such as CO and NO2-. The genes encoding the large and small subunits of a periplasmic and a membrane-bound species of the [NiFe] hydrogenase have been cloned in Escherichia (E.) coli and sequenced. Their derived amino acid sequences exhibit a high degree of homology (70%); however, they show no obvious metal-binding sites or homology with the derived amino acid sequence of the [Fe] hydrogenase. The third class is represented by the nickel-(iron-sulfur)-selenium-containing hydrogenases [( NiFe-Se] hydrogenases) which contain nickel and selenium in equimolecular amounts plus (4Fe-4S) centers and are only found in some species of Desulfovibrio. The genes encoding the large and small subunits of the periplasmic hydrogenase from Desulfovibrio (D.) baculatus (DSM 1743) have been cloned in E. coli and sequenced. The derived amino acid sequence exhibits homology (40%) with the sequence of the [NiFe] hydrogenase and the carboxy-terminus of the gene for the large subunit contains a codon (TGA) for selenocysteine in a position homologous to a codon (TGC) for cysteine in the large subunit of the [NiFe] hydrogenase. EXAFS and EPR studies with the 77Se-enriched D. baculatus hydrogenase indicate that selenium is a ligand to nickel and suggest that the redox active nickel is ligated by at least two cysteinyl thiolate and one selenocysteine selenolate residues.(ABSTRACT TRUNCATED AT 400 WORDS)
已从脱硫弧菌属的硫酸盐还原细菌中分离出三种类型的氢化酶。它们在亚基和金属组成、物理化学特性、氨基酸序列、免疫反应性、基因结构及其催化特性方面存在差异。大致来说，氢化酶可分为“仅含铁”氢化酶和含镍氢化酶。含铁硫氢化酶（[Fe]氢化酶）含有两个铁氧化还原蛋白型（4Fe - 4S）簇和一个非典型的铁硫中心，据信该中心参与H₂的活化。[Fe]氢化酶在氢气的产生和消耗以及质子 - 氘交换反应中具有最高的比活性，并且这种酶对CO和NO₂⁻最为敏感。它并非存在于所有脱硫弧菌物种中。含镍 - （铁硫）氢化酶（[NiFe]氢化酶）除镍外还拥有两个（4Fe - 4S）中心和一个（3Fe - xS）簇，并且在迄今为止研究的所有脱硫弧菌物种中都已发现。氧化还原活性镍至少与两个半胱氨酸硫醇盐残基相连，并且[NiFe]氢化酶对诸如CO和NO₂⁻等抑制剂具有特别的抗性。编码[NiFe]氢化酶的周质和膜结合型大亚基和小亚基的基因已在大肠杆菌中克隆并测序。它们推导的氨基酸序列显示出高度同源性（70%）；然而，它们没有明显的金属结合位点，也与[Fe]氢化酶推导的氨基酸序列没有同源性。第三类以含镍 - （铁硫） - 硒氢化酶（[NiFe - Se]氢化酶）为代表，其含有等摩尔量的镍和硒以及（4Fe - 4S）中心，并且仅在一些脱硫弧菌物种中发现。编码来自杆状脱硫弧菌（DSM 1743）的周质氢化酶大亚基和小亚基的基因已在大肠杆菌中克隆并测序。推导的氨基酸序列与[NiFe]氢化酶的序列具有同源性（40%），并且大亚基基因的羧基末端在与[NiFe]氢化酶大亚基中半胱氨酸密码子（TGC）同源的位置含有一个硒代半胱氨酸密码子（TGA）。对富含⁷⁷Se的杆状脱硫弧菌氢化酶的扩展X射线吸收精细结构（EXAFS）和电子顺磁共振（EPR）研究表明，硒是镍的配体，并表明氧化还原活性镍至少与两个半胱氨酸硫醇盐和一个硒代半胱氨酸硒醇盐残基相连。（摘要截断于400字）
