Le Deaut J Y, Roussel G, Delaunoy J P, Ledig M, Mandel P
Biochimie. 1978;60(11-12):1243-52. doi: 10.1016/s0300-9084(79)80441-1.
We described previously the existence of a soluble ATPase activity in rat liver mitochondria [1]. The purification and catalytic properties have been described [2]. In a continuation of these experiments, we have studied the immunologic and structural properties of one molecular form of this enzyme : ATPase I. We have prepared the antiserum anti-ATPase I and demonstrated the purity of our enzyme preparation by immunodiffusion and immunoelectrophoresis. An immunohistochemical method also confirmed the localization of ATPase I in the soluble fraction of mitochondria. The molecular weight of ATPase I was measured by G 100 Sephadex gel filtration and was found to be 18,400; electrophoresis on polyacrylamide gels gave a value of 18,600. The pHi of ATPase I was found to be 7,2. Amino acid analysis showed high amounts of aspartic acid, glutamic acid, serine and glycine. The molecular weight calculated from the total amino acid residues was found to be 17,000. Alanine is the NH2 terminal amino acid. The peptide maps obtained after degrading ATPase I with cyanogen bromide or trypsin are in accordance with the methionine, lysine and arginine residues we found in the ATPase I molecule. ATPase I does not appear to be a glycoprotein.
我们先前曾描述过大鼠肝线粒体中存在一种可溶性ATP酶活性[1]。其纯化及催化特性已有报道[2]。在这些实验的后续研究中，我们对这种酶的一种分子形式——ATP酶I的免疫学和结构特性进行了研究。我们制备了抗ATP酶I抗血清，并通过免疫扩散和免疫电泳证明了我们酶制剂的纯度。免疫组织化学方法也证实了ATP酶I在线粒体可溶部分中的定位。通过G 100葡聚糖凝胶过滤法测得ATP酶I的分子量为18,400；在聚丙烯酰胺凝胶上进行电泳得到的值为18,600。发现ATP酶I的pH值为7.2。氨基酸分析显示含有大量的天冬氨酸、谷氨酸、丝氨酸和甘氨酸。根据总氨基酸残基计算出的分子量为17,000。丙氨酸是NH2末端氨基酸。用溴化氰或胰蛋白酶降解ATP酶I后得到的肽图与我们在ATP酶I分子中发现的甲硫氨酸、赖氨酸和精氨酸残基相符。ATP酶I似乎不是一种糖蛋白。
