Hensel M, Deckers-Hebestreit G, Altendorf K
Arbeitsgruppe Mikrobiologie, Fachbereich Biologie/Chemie, Universität Osnabrück, Federal Republic of Germany.
Eur J Biochem. 1991 Dec 18;202(3):1313-9. doi: 10.1111/j.1432-1033.1991.tb16505.x.
The F1 complex of the ATP synthase of Streptomyces lividans was isolated and purified. The procedure involved the solubilization of F1 from membranes with buffer of low ionic strength in the presence of EDTA, ion-exchange chromatography and gel filtration. The purified F1 complex from S. lividans (SLF1) consists of five subunits alpha, beta, gamma, delta and epsilon with molecular masses of 58,000, 50,000, 36,000, 28,000 and 13,000, respectively and exhibits immunological cross-reactivity with the F1 portion purified from Escherichia coli (ECF1). The enzymatic properties of SLF1 were determined by the use of microtiter-plate-based assay and compared with data obtained for ECF1. ATPase activity of SLF1 (specific activity: 20-30 U/mg) was only observed in the presence of high concentrations of Ca2+ (10mM). Stimulation of the ATPase activity by Mg2+ was not detectable; quite to the contrary, Mg2+ inhibited the Ca(2+)-stimulated activity of SLF1. SLF1 was re-bound to F1-stripped membranes of S. lividans, but not to F1-stripped membrane vesicles of E. coli. In contrast, ECF1 could be cross-reconstituted with F1-stripped membranes of S. lividans; however, a structural but not a functional reconstitution of the hybrid F1Fo complex was observed.
对淡紫链霉菌ATP合酶的F1复合物进行了分离和纯化。该过程包括在EDTA存在下，用低离子强度缓冲液从膜中溶解F1，进行离子交换色谱和凝胶过滤。从淡紫链霉菌纯化得到的F1复合物（SLF1）由α、β、γ、δ和ε五个亚基组成，分子量分别为58,000、50,000、36,000、28,000和13,000，并且与从大肠杆菌纯化得到的F1部分（ECF1）表现出免疫交叉反应性。通过基于微量滴定板的测定法确定了SLF1的酶学性质，并与ECF1的数据进行了比较。SLF1的ATP酶活性（比活性：20 - 30 U/mg）仅在高浓度Ca2+（10 mM）存在时才观察到。未检测到Mg2+对ATP酶活性的刺激作用；相反，Mg2+抑制了SLF1的Ca(2+)刺激活性。SLF1重新结合到淡紫链霉菌的F1去除型膜上，但不结合到大肠杆菌的F1去除型膜囊泡上。相比之下，ECF1可以与淡紫链霉菌的F1去除型膜进行交叉重组；然而，观察到的是杂合F1Fo复合物的结构重组而非功能重组。
