Lipid environment of gastric potassium ion-stimulated adenosine triphosphatase.
Lipid environment of gastric potassium ion-stimulated adenosine triphosphatase.
复制标题
胃钾离子刺激的三磷酸腺苷酶的脂质环境。
作者：
P. Sen;T. Ray
在37 ℃下用15%（v/v）乙醇处理60 s可完全灭活与纯化的胃微粒体组分相关的K+刺激的ATP酶，但在25 ℃下则不能。在25 ℃和37 ℃下将微粒体组分依次暴露于15%乙醇中，分别释放2.5%和2.9%的总膜磷脂。在Mg 2+，K+和ATP的存在下，通过超声处理与磷脂酰胆碱，这是必不可少的重建的酶活性的恢复。我们的数据表明，在37 ℃下由15%乙醇提取的磷脂主要来自酶的直接脂质环境，并且ATP与金属离子一起帮助部分脱脂的酶保留适当的构型用于随后的重构。
The K+-stimulated ATPase associated with the purified gastric microsomal fraction can be completely inactivated by treatment with 15% (v/v) ethanol for 60s at 37 degrees C, but not at 25 degrees C. Sequential exposure of the microsomal fraction to 15% ethanol at 25 degrees C and 37 degrees C caused release of 2.5% and 2.9% of the total membrane phospholipids respectively. Restoration of the enzyme activity was achieved by sonication with phosphatidylcholine in the presence of Mg2+, K+ and ATP, which were essential for the reconstitution. Our data suggest that the phospholipids extracted by 15% ethanol at 37 degrees C are derived primarily from the immediate lipid environment of the enzyme, and ATP, together with the metal ions, helps the partially delipidated enzyme to retain the appropriate configuration for the subsequent reconstitution.