A decade ago, four independent groups reported the unanticipated and still surprising result that the bending modulus κ of bilayers of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), unlike other standard lipids, does not increase with addition of cholesterol. This was shown from tube pulling (1, 2) shape analysis (SA) and electro-deformation (ED) of giant vesicles (3), and X-ray diffuse scattering (XDS) fluctuations in bilayer stacks (4). However, a recent PNAS paper (5) based on neutron spin echo (NSE) and NMR relaxation (NMRR) claims that the bending modulus of DOPC increases threefold for cholesterol mole fractions of 50%. Thus, it would appear that this is a controversial topic for understanding membrane mechanics.

中文翻译：

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一个不必要但有趣的争论[物理科学]

十年前，四个独立小组报告了出乎意料且仍然令人惊讶的结果，即 1,2- dioleoyl- sn -glycero-3-phosphocholine (DOPC)双层的弯曲模量 κ与其他标准脂质不同，不会随着添加胆固醇。这从巨型囊泡 ( 3 ) 的拉管 ( 1 , 2 ) 形状分析 (SA) 和电变形 (ED) 以及双层堆叠 ( 4 ) 中的X 射线漫散射 (XDS) 波动中显示出来。然而，最近的 PNAS 论文（5) 基于中子自旋回波 (NSE) 和 NMR 弛豫 (NMRR) 声称，对于 50% 的胆固醇摩尔分数，DOPC 的弯曲模量增加了三倍。因此，这似乎是理解膜力学的一个有争议的话题。