Structure and Dynamics of the Central Lipid Pool and Proteins of the Bacterial Holo-Translocon.
Structure and Dynamics of the Central Lipid Pool and Proteins of the Bacterial Holo-Translocon.
复制标题
细菌全息子中心脂质池和蛋白质的结构和动力学。
DOI：
10.1016/j.bpj.2019.04.002
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发表时间：
2019
影响因子：
3.4
通讯作者：
Martin R
中科院分区：
文献类型：
--
作者：
Martin R
细菌Sec易位子SecYEG与辅助蛋白YidC和SecDF-YajC亚复合物结合形成细菌全易位子（HTL）。HTL是一种动态和灵活的蛋白质转运机器，能够协调跨膜的蛋白质分泌和新生膜蛋白的有效侧向插入。据推测，一个中央脂质核心促进膜蛋白进入双层的控制通道，确保其天然状态的有效形成。通过对溶解在“匹配”氘代洗涤剂中的蛋白质进行小角度中子散射，我们已经能够询问“裸”HTL复合物，周围洗涤剂胶束的散射贡献不可见。这种方法允许确认HTL内的脂质核心，其容纳8至29个脂质。粗粒度的分子动力学模拟的HTL也表现出一个动态的，中央池的脂质。在YidC和SecY侧门之间的这个富含脂质的区域的开口可以为新合成的、正确定向的膜蛋白螺旋或甚至小束螺旋从HTL出现提供出口通道。
The bacterial Sec translocon, SecYEG, associates with accessory proteins YidC and the SecDF-YajC subcomplex to form the bacterial holo-translocon (HTL). The HTL is a dynamic and flexible protein transport machine capable of coordinating protein secretion across the membrane and efficient lateral insertion of nascent membrane proteins. It has been hypothesized that a central lipid core facilitates the controlled passage of membrane proteins into the bilayer, ensuring the efficient formation of their native state. By performing small-angle neutron scattering on protein solubilized in "match-out" deuterated detergent, we have been able to interrogate a "naked" HTL complex, with the scattering contribution of the surrounding detergent micelle rendered invisible. Such an approach has allowed the confirmation of a lipid core within the HTL, which accommodates between 8 and 29 lipids. Coarse-grained molecular dynamics simulations of the HTL also demonstrate a dynamic, central pool of lipids. An opening at this lipid-rich region between YidC and the SecY lateral gate may provide an exit gateway for newly synthesized, correctly oriented, membrane protein helices, or even small bundles of helices, to emerge from the HTL.