Schoenmaker G S, Oltmann L F, Stouthamer A H
Biochim Biophys Acta. 1979 Apr 12;567(2):511-21. doi: 10.1016/0005-2744(79)90137-2.
The cytoplasmic membrane-bound hydrogenase of the facultative anaerobe, Proteus mirabilis, has been solubilized and purified to homogeneity. The purified enzyme exhibited a maximal specific activity of about 780 mumol H2 oxidized/min per mg protein (benzyl viologen reduction). The hydrogenase has a molecular weight of 205 000 and is composed of two subunits with a molecular weight of 63 000 and two of 33 000. The absorption spectrum of the enzyme was characteristic of non-heme iron proteins. The millimolar extinction coefficients at 400 and 280 nm are 106 and 390, respectively. The hydrogenase has about 24 iron atoms and 24 acid-labile sulfide atoms/molecule. Amino acid analyses revealed the presence of 39 half-cystine residues/molecule and a preponderance of acidic amino acids. The hydrogenase in its oxidized form exhibits an EPR signal of the HiPIP-type with g values at 2.025 and 2.018. Upon reduction with either dithionite or H2 the signal disappears; no other signals were detectable.
兼性厌氧菌奇异变形杆菌的细胞质膜结合氢化酶已被溶解并纯化至同质。纯化后的酶表现出约780 μmol H₂氧化/（分钟·毫克蛋白）（苄基紫精还原）的最大比活性。该氢化酶分子量为205000，由两个分子量为63000的亚基和两个分子量为33000的亚基组成。该酶的吸收光谱是非血红素铁蛋白的特征光谱。在400和280 nm处的毫摩尔消光系数分别为106和390。该氢化酶每个分子约有24个铁原子和24个酸不稳定硫化物原子。氨基酸分析显示每个分子存在39个半胱氨酸残基且酸性氨基酸占优势。氧化形式的氢化酶表现出HiPIP型的电子顺磁共振信号，g值为2.025和2.018。用连二亚硫酸盐或H₂还原后信号消失；未检测到其他信号。
