Hatchikian E C, Forget N, Bernadac A, Alazard D, Ollivier B
Unité de Bioénergétique et Ingéniérie des Protéines, CNRS, Marseille, France.
Res Microbiol. 1995 Feb;146(2):129-41. doi: 10.1016/0923-2508(96)80891-6.
Various sulphate-reducing bacteria differing in the number of genes encoding hydrogenase were shown to ferment lactate in coculture with Methanospirillum hungatei, in the absence of sulphate. The efficiency of interspecies H2 transfer carried out by these species of sulphate-reducing bacteria does not appear to correlate with the distribution of genes coding for hydrogenase. Desulfovibrio vulgaris Groningen, which possesses only the gene for [NiFe] hydrogenase, oxidizes hydrogen in the presence of sulphate and produces some hydrogen during fermentation of pyruvate without electron acceptor. The hydrogenase of D. vulgaris was purified and characterized. It exhibits a molecular mass of 87 kDa and is composed of two different subunits (60 and 28 kDa). D. vulgaris hydrogenase contains 10.6 iron atoms, 0.9 nickel atom and 12 acid-labile sulphur atoms/molecule, and the absorption spectrum of the enzyme is characteristic of an iron-sulphur protein. Maximal H2 uptake and H2 evolution activities were 332 and 230 units/mg protein, respectively. D. vulgaris cells contain exclusively the [NiFe] hydrogenase, whatever the growth conditions, as shown by biochemical and immunological studies. Immunocytolocalization in ultrathin frozen sections of cells grown on lactate and sulphate, on H2 and sulphate and on pyruvate showed that the [NiFe] hydrogenase was located in the periplasmic space. Labelling was enhanced in cells grown on H2 and sulphate and on pyruvate. The results enable us to conclude that D. vulgaris Groningen contains a single hydrogenase of the [NiFe] type, located in the periplasmic space like that described for D. gigas. This enzyme appears to be involved in both H2 uptake and H2 production, depending on the growth conditions.
已证明，在缺乏硫酸盐的情况下，多种编码氢化酶基因数量不同的硫酸盐还原菌与亨氏甲烷螺菌共培养时可发酵乳酸。这些硫酸盐还原菌进行种间氢气转移的效率似乎与编码氢化酶的基因分布无关。普通脱硫弧菌格罗宁根菌株仅拥有[NiFe]氢化酶基因，在有硫酸盐存在时氧化氢气，并在无电子受体的丙酮酸发酵过程中产生一些氢气。对普通脱硫弧菌的氢化酶进行了纯化和特性分析。它的分子量为87 kDa，由两个不同的亚基（60 kDa和28 kDa）组成。普通脱硫弧菌氢化酶每分子含有10.6个铁原子、0.9个镍原子和12个酸不稳定硫原子，该酶的吸收光谱具有铁硫蛋白的特征。最大氢气摄取和氢气释放活性分别为332和230单位/毫克蛋白。生化和免疫学研究表明，无论生长条件如何，普通脱硫弧菌细胞仅含有[NiFe]氢化酶。对在乳酸和硫酸盐、氢气和硫酸盐以及丙酮酸上生长的细胞超薄冷冻切片进行免疫细胞定位显示，[NiFe]氢化酶位于周质空间。在氢气和硫酸盐以及丙酮酸上生长的细胞中标记增强。这些结果使我们能够得出结论，普通脱硫弧菌格罗宁根菌株含有一种单一的[NiFe]型氢化酶，位于周质空间，如同对巨大脱硫弧菌所描述的那样。根据生长条件，这种酶似乎既参与氢气摄取又参与氢气产生。
