INTRINSIC CURVATURE HYPOTHESIS FOR BIOMEMBRANE LIPID-COMPOSITION - A ROLE FOR NONBILAYER LIPIDS
INTRINSIC CURVATURE HYPOTHESIS FOR BIOMEMBRANE LIPID-COMPOSITION - A ROLE FOR NONBILAYER LIPIDS
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DOI：
10.1073/pnas.82.11.3665
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发表时间：
1985-01-01
影响因子：
11.1
通讯作者：
GRUNER, SM
中科院分区：
文献类型：
--
作者：
GRUNER, SM
双层和非双层脂质的混合物，发生在生物膜的一个理由。关于L α的理论本文综述了HII相变理论及其实验验证。相行为显然主要是某些脂质单分子层卷曲的趋势与由此产生的烃类堆积应变之间竞争的结果。卷曲的趋势由固有曲率半径Ro定量给出，其使脂质单层的弯曲能最小化。当双层（大Ro）和非双层（小Ro）脂质适当混合时，所得层的Ro值处于双层稳定性的临界边缘。在这种情况下，双层可以通过蛋白质介导的疏水分子如多萜醇的引入而不稳定。描述了长萜醇对这样的脂质混合物的影响的X-射线衍射调查。这导致了假设，即生物膜同源统计地调整其内在曲率落入一个最佳范围。实验策略测试的假设进行了概述。
A rationale is presented for the mix of bilayer and nonbilayer lipids, which occurs in biomembranes. A theory for the L.alpha.-HII phase transition and experimental tests of the theory are reviewed. The phase behavior apparently is largely the result of a competition between the tendency for certain lipid monolayers to curl and the hydrocarbon packing strains that result. The tendency to curl is quantitatively given by the intrinsic radius of curvature, Ro, which minimizes the bending energy of a lipid monolayer. When bilayer (large Ro) and nonbilayer (small Ro) lipids are properly mixed, the resulting layer has value of Ro that is at the critical edge of bilayer stability. In this case, bilayers may be destabilized by the protein-mediated introduction of hydrophobic molecules, such as dolichol. An X-ray diffraction investigation of the effect of dolichol on such a lipid mixture is described. This leads to the hypthesis that biomembranes homeostatistically adjust their intrinsic curvatures to fall into an optimum range. Experimental strategies for testing the hypothesis are outlined.