Abstract:
Single particle cryo electron microscopy (cryo-EM) is now the major method for the determination of integral membrane protein structure. For the success of a given project the type of membrane mimetic used for extraction from the native cell membrane, purification to homogeneity and finally cryo-grid vitrification is crucial. Although small molecule amphiphiles - detergents - are the most widely used membrane mimetic, specific tailoring of detergent structure for single particle cryo-EM is rare and the demand for effective detergents not satisfied. Here, we compare the popular detergent lauryl maltose-neopentyl glycol (LMNG) with the novel detergent neopentyl glycol-derived triglucoside-C11 (NDT-C11) in its behavior as free detergent and when bound to two types of multisubunit membrane protein complexes - cyanobacterial photosystem I (PSI) and mammalian F-ATP synthase. We conclude that NDT-C11 has high potential to become a very useful detergent for single particle cryo-EM of integral membrane proteins.
摘要:
单粒子低温电子显微镜(cryo-EM)现在是测定完整膜蛋白结构的主要方法。对于给定项目的成功,用于从天然细胞膜中提取的膜模拟物的类型,纯化到均质和最终的低温网格玻璃化是至关重要的。虽然小分子两亲物-洗涤剂-是最广泛使用的膜模拟物,单颗粒低温EM洗涤剂结构的具体定制很少,对有效洗涤剂的需求也得不到满足。这里,我们比较了流行的去污剂月桂基麦芽糖-新戊二醇(LMNG)和新型去污剂新戊二醇衍生的三葡糖苷-C11(NDT-C11)作为游离去污剂的行为,以及与两种类型的多亚基膜蛋白复合物结合时的行为-蓝细菌光系统I(PSI)和哺乳动物F-ATP合酶。我们得出的结论是,NDT-C11具有很高的潜力,可以成为完整膜蛋白的单颗粒低温EM的非常有用的去污剂。