Exclusive labeling of the extracytoplasmic surface of sodium ion and potassium ion activated adenosinetriphosphatase and a determination of the distribution of surface area across the bilayer.
Exclusive labeling of the extracytoplasmic surface of sodium ion and potassium ion activated adenosinetriphosphatase and a determination of the distribution of surface area across the bilayer.
复制标题
独家标记钠离子和钾离子激活的三磷酸腺苷酶的胞质外表面，并确定双层的表面积分布。
DOI：
10.1021/bi00266a040
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发表时间：
1982
期刊：
影响因子：
2.9
通讯作者：
O'Connell,MA
中科院分区：
文献类型：
--
作者：
O'Connell,MA
Mary A. O’Connell 摘要：使用重氮化/>[35S]磺胺酸和密封囊泡的不渗透性蛋白质修饰试剂测定了脂双层两侧之间钠离子和钾离子激活的腺苷三磷酸酶 [(Na++ K+)-ATPase] 的 a 亚基的亲水表面积的相对分布。使用两种类型的囊泡：用磷脂酰胆碱重构的(Na++K+)-ATP酶和自发密封的粗膜囊泡。通过测量酶潜伏期和密度梯度浮选，表明两者都被小分子密封。在重建囊泡的情况下，对任何以内向外方向存在的a亚基进行选择性蛋白水解消化，仅允许测量a亚基的细胞质外部分的标记程度，因为具有相反方向的亚基不受蛋白水解处理的影响。另一方面，自发地
Mary A. O’Connell abstract: The relative distribution of the hydrophilic surface area of the a subunit of sodium ion and potassium ion activated adenosinetriphosphatase [(Na++ K+)-ATPase] between the two sides of the lipid bilayer was determined with the im-permeant protein modifying reagent diazotized/>[35S] sulfanilic acid and sealed vesicles. Two types of vesicles,(Na++ K+)-ATPase reconstituted with phosphatidylcholine and spontaneously sealed, crude membrane vesicles, were used. Both were shown to be sealed to small molecules by mea-surements of enzymatic latency and by flotation on density gradients. In the case of the reconstituted vesicles, selective proteolytic digestion of any a subunit present with an inside-out orientation allowed theextent of labeling of only the extra-cytoplasmic portion of the a subunit to be measured since a subunits with the opposite orientation were unaffected by the proteolytic treatment. On the other hand, the spontaneously