Department of Physiology and Biophysics, Aarhus University, Ole Worms Allé 6, DK-8000 Aarhus, Denmark.
Biochem Biophys Res Commun. 2011 Mar 25;406(4):580-3. doi: 10.1016/j.bbrc.2011.02.094. Epub 2011 Feb 23.
The thermal stability of Na,K-ATPase from pig kidney is markedly greater than that of Na,K-ATPase from shark salt glands. The role of the lipid bilayer is studied by solubilisation of the membrane-bound enzyme in the nonionic detergent octaethyleneglycoldodecylmonoether (C(12)E(8)), addition of excess dioleylphosphatidylcholine (DOPC) or palmitoyloleylphosphatidylcholine (POPC) and reconstitution of membranes by removal of detergent. At 54°C the reconstituted enzymatically active pig enzyme retains a high thermal stability, and reconstituted shark enzyme retains a low thermal stability, even with a 9-fold excess of DOPC. This result suggests that the origin of the difference in thermal stability is not related to bulk lipid properties of the native membranes.
猪肾钠钾-ATP 酶的热稳定性明显高于鲨鱼盐腺钠钾-ATP 酶。通过非离子型去污剂辛基乙二醇十二醚（C12E8）溶解膜结合酶，添加过量二油酰基磷脂酰胆碱（DOPC）或棕榈酰油酰基磷脂酰胆碱（POPC），并通过去除去污剂重新构建膜来研究脂质双层的作用。在 54°C 下，重组的具有酶活性的猪酶保持高的热稳定性，而重组的鲨鱼酶即使有 9 倍过量的 DOPC 也保持低的热稳定性。这一结果表明，热稳定性差异的起源与天然膜的大量脂质性质无关。
