Rieder R, Cammack R, Hall D O
Eur J Biochem. 1984 Dec 17;145(3):637-43. doi: 10.1111/j.1432-1033.1984.tb08604.x.
A soluble hydrogenase has been isolated from Desulfovibrio desulfuricans (strain Norway 4) grown on Postgate's medium. The enzyme differs significantly from a membrane-bound hydrogenase previously purified from the same organism grown on Starkey's medium. The enzyme consisted of two subunits of 56 kDa and 29 kDa compared with masses of 60 kDa and 27 kDa for the membrane-bound enzyme. Analysis of preparations of the soluble enzyme by various methods gave values of 5-10 iron atoms, 6 labile sulphur atoms and 0.45-0.8 nickel atom per molecule. The enzyme was unusual in that it contained selenium, in quantities equivalent to nickel. The highly purified active enzyme produced no electron-spin-resonance (ESR) signals in the oxidized state. ESR signals due to a [3Fe-xS] cluster and nickel were observed only in some of the less active fractions of the enzyme, demonstrating that neither of these ESR-detectable components is a prerequisite for hydrogenase activity. Treatment of D. desulfuricans (Norway) cells with EDTA released a minor fraction with hydrogenase activity, which might indicate the presence of a periplasmic enzyme.
从在波斯特盖特培养基上生长的脱硫脱硫弧菌（挪威4菌株）中分离出了一种可溶性氢化酶。该酶与先前从在斯塔基培养基上生长的同一生物体中纯化出的膜结合氢化酶有显著差异。该酶由56 kDa和29 kDa的两个亚基组成，而膜结合酶的质量为60 kDa和27 kDa。通过各种方法对可溶性酶制剂进行分析，结果表明每个分子含有5 - 10个铁原子、6个不稳定硫原子和0.45 - 0.8个镍原子。该酶的不同寻常之处在于它含有相当于镍含量的硒。高度纯化的活性酶在氧化状态下不产生电子自旋共振（ESR）信号。仅在该酶的一些活性较低的组分中观察到了由于[3Fe - xS]簇和镍产生的ESR信号，这表明这些可通过ESR检测到的组分都不是氢化酶活性的先决条件。用EDTA处理脱硫脱硫弧菌（挪威）细胞会释放出一小部分具有氢化酶活性的组分，这可能表明存在一种周质酶。
