Analysis of the PilQ secretin from Neisseria meningitidis by transmission electron microscopy reveals a dodecameric quaternary structure
Analysis of the PilQ secretin from Neisseria meningitidis by transmission electron microscopy reveals a dodecameric quaternary structure
复制标题
DOI：
10.1128/jb.183.13.3825-3832.2001
复制
发表时间：
2001-07-01
影响因子：
3.2
通讯作者：
Tonjum, T
中科院分区：
文献类型：
--
作者：
Collins, RF;Davidsen, L;Tonjum, T
PilQ 是外膜蛋白促胰液素家族的成员，专门参与脑膜炎奈瑟菌、淋病奈瑟菌和铜绿假单胞菌中 TV 型丸的分泌。使用负染色通过透射电子显微镜分析了脑膜炎奈瑟菌 PilQ 的四级结构。对 650 个单独颗粒的总数据集进行了单颗粒平均，产生了由 296 个颗粒生成的投影图，估计分辨率为 2.6 nm。Oligomeric PilQ 采用甜甜圈状结构，外环直径为 16.5 nm，中心空腔直径为 6.5 nm。自旋转酸功率谱分析证明存在12重旋转对称性，表明PilQ被组织为由12个相同亚基组成的环。IV型脑膜炎球菌菌毛纤维模型，基于淋病奈瑟菌菌毛蛋白亚基的X射线晶体结构，整齐地安装在空腔中，展示了PilQ如何充当生长菌毛纤维的通道。
PilQ is a member of the secretin family of outer membrane proteins and is specifically involved in secretion of type TV pill in Neisseria meningitidis, Neisseria gonorrhoeae, and Pseudomonas aeruginosa, The quaternary structure of PilQ from N. meningitidis was analyzed by transmission electron microscopy by using a negative stain. Single particle averaging was carried out with a total data set of 650 individual particles, which produced a projection map generated from 296 particles at an estimated resolution of 2.6 nm, Oligomeric PilQ adopts a donut-like structure with an external ring that is 16.5 nm in diameter surrounding a central cavity that is 6.5 nm in diameter. Self-rotation acid power spectrum analysis demonstrated the presence of 12-fold rotational symmetry, showing that PilQ is organized as a ring of 12 identical subunits, A model of the type IV meningococcal pilus fiber, based on the X-ray crystal structure of the N. gonorrhoeae pilin subunit, fitted neatly into the cavity, demonstrating how PilQ could serve as a channel for the growing pilus fiber.