Muntyan M S, Mesyanzhinova I V, Milgrom Y M, Skulachev V P
A.N. Belozersky Laboratory of Molecular Biology and Bioorganic Chemistry, Moscow State University, U.S.S.R.
Biochim Biophys Acta. 1990 Apr 26;1016(3):371-7. doi: 10.1016/0005-2728(90)90171-y.
An ATPase from anaerobic Lactobacillus casei has been isolated and 100-times purified. The 400 kDa enzyme molecule was found to have a hexagonal structure 10 nm in diameter composed of at least six protein masses. SDS-electrophoresis reveals four or, under certain conditions, five types of subunit, of apparent molecular masses 57 (alpha), 55 (beta), 40 (gamma), 22 (delta) and 14 (epsilon) kDa with stoichiometry of 3 alpha, 3 beta, gamma, delta, epsilon. The following features resembling F1-ATPases from other sources were found to be inherent in the solubilized L. casei ATPase. (i) Detachment from the membrane desensitizes ATPase to low DCCD concentrations and sensitizes it to water-soluble carbodiimide. (ii) Soluble ATPase is inhibited by Nbf chloride and azide, is resistant to SH-modifiers and is activated by sulfite and octyl glucoside, the activating effect being much stronger than in the case of the membrane-bound ATPase. Substrate specificity of the enzyme is also similar to that of other factors F1. Divalent cations strongly activate the soluble enzyme when added at a concentration equal to that of ATP. An excess of Mn2+, Mg2+ or Co2+ inhibits ATPase activity of F1, whereas that of Ca2+ induces its further activation. No other F1-like ATPases are found in L. casei. It is concluded that this anaerobic bacterium possesses a typical F1-ATPase similar to those in mitochondria, chloroplasts, aerobic and photosynthetic eubacteria.
已从厌氧干酪乳杆菌中分离出一种ATP酶，并进行了100倍的纯化。发现该400 kDa的酶分子具有直径为10 nm的六边形结构，由至少六个蛋白质块组成。SDS电泳显示有四种，在某些条件下为五种亚基类型，其表观分子量分别为57（α）、55（β）、40（γ）、22（δ）和14（ε）kDa，化学计量比为3α、3β、γ、δ、ε。在溶解的干酪乳杆菌ATP酶中发现了以下类似于其他来源的F1-ATP酶的特征。（i）从膜上分离会使ATP酶对低浓度的DCCD不敏感，并使其对水溶性碳二亚胺敏感。（ii）可溶性ATP酶受Nbf氯化物和叠氮化物抑制，对SH修饰剂有抗性，并被亚硫酸盐和辛基葡糖苷激活，其激活作用比膜结合ATP酶的情况要强得多。该酶的底物特异性也与其他F1因子相似。当以与ATP相同的浓度添加二价阳离子时，会强烈激活可溶性酶。过量的Mn2+、Mg2+或Co2+会抑制F1的ATP酶活性，而Ca2+则会诱导其进一步激活。在干酪乳杆菌中未发现其他类似F1的ATP酶。结论是，这种厌氧细菌拥有一种典型的F1-ATP酶，类似于线粒体、叶绿体、需氧和光合真细菌中的F1-ATP酶。
