The effect of bilayer thickness and n-alkanes on the activity of the (Ca2+ + Mg2+)-dependent ATPase of sarcoplasmic reticulum.
The effect of bilayer thickness and n-alkanes on the activity of the (Ca2+ + Mg2+)-dependent ATPase of sarcoplasmic reticulum.
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DOI：
10.1016/s0021-9258(19)69855-8
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发表时间：
1981-02
期刊：
影响因子：
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通讯作者：
A. Johannsson;C. Keightley;G. Smith;C. D. Richards;T. Hesketh;J. Metcalfe
中科院分区：
文献类型：
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作者：
A. Johannsson;C. Keightley;G. Smith;C. D. Richards;T. Hesketh;J. Metcalfe
由一系列磷脂酰胆碱（PC）支持的(Ca2++ Mg2+)- atp酶的活性与长度从n= 12到n= 23不等的不饱和（顺式9）脂肪酰基链（di (n: 1) PC）通过脂质滴定技术测定（Warren， GB, Toon， P. a ., Birdsall, n . J. M., Lee, a.g ., and Metcalfe， J. C.（1974）生物化学13,5501-5507）。37℃时，atp酶活性随着脂质链长度的增加而增加，从0.06 pmol min“mg”蛋白（n= 12）增加到16 pmol min (n= 20)，而与di (23: 1) PC复合物的atp酶活性则下降到12 pmol min （n= 20）。所有atp酶活性随PC链长度的变化通过脂质交换滴定是可逆的。含有两个di (n: 1) PCs混合物的双层支持atp酶活性，其大致对应于脂质混合物的平均链长。数据表明，决定这些复合物中atp酶活性的主要因素是脂质双分子层的厚度。二（n: 1） PC- atp酶复合物用癸烷处理，先前显示可以增加卵PC黑脂膜的双层厚度（Fettiplace， R., Andrews， D. M.和Haydon， D. A.）。
The activities of the (Ca2++ Mg2+)-ATPase from sar-coplasmic reticulum supported by a series of phosphatidylcholines (PC) with unsaturated (cis 9) fatty acyl chains (di (n: l) PC) varying in length from n= 12 to n= 23 were determined by the lipid titration technique (Warren, GB, Toon, P. A., Birdsall, N. J. M., Lee, A. G., and Metcalfe, J. C.(1974) Biochemistry 13, 5501-5507). The ATPase activity at 37 C increased with lipid chain length in the PC bilayer from 0.06 pmol min" mg" of protein (n= 12) to a maximum of 16 (n= 20) and decreased to 12 for complexes of the ATPase with di (23: l) PC. All ATPase activity changes with PC chain length were reversible by lipid exchange titrations. Bilayers containing mixtures of two di (n: l) PCs supported ATPase activities which corresponded approximately to the average chain length of the lipid mixture. The data indicate that the major factor determining ATPase activity in these complexes is the thickness of the lipid bilayer. The di (n: l) PC-ATPase complexes were treated with decane, previously shown to increase bilayer thickness in black lipid membranes of egg PC (Fettiplace, R., Andrews, D. M., and Haydon, D. A.