Lipid Biology Laboratory, RIKEN, 2-1, Wako, Saitama, Japan; NanoLSI, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa, Japan.
Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia.
J Biol Chem. 2023 Aug;299(8):104940. doi: 10.1016/j.jbc.2023.104940. Epub 2023 Jun 19.
Ostreolysin A6 (OlyA6) is an oyster mushroom-derived membrane-binding protein that, upon recruitment of its partner protein, pleurotolysin B, forms a cytolytic membrane pore complex. OlyA6 itself is not cytolytic but has been reported to exhibit pro-apoptotic activities in cell culture. Here we report the formation dynamics and the structure of OlyA6 assembly on a lipid membrane containing an OlyA6 high-affinity receptor, ceramide phosphoethanolamine, and cholesterol. High-speed atomic force microscopy revealed the reorganization of OlyA6 dimers from initial random surface coverage to 2D protein crystals composed of hexameric OlyA6 repeat units. Crystal growth took place predominantly in the longitudinal direction by the association of OlyA6 dimers, forming a hexameric unit cell. Molecular-level examination of the OlyA6 crystal elucidated the arrangement of dimers within the unit cell and the structure of the dimer that recruits pleurotolysin B for pore formation.
牡蛎菇衍生的膜结合蛋白 Ostreolysin A6（OlyA6），在与其伴侣蛋白 pleurotolysin B 募集后，形成溶细胞膜孔复合物。OlyA6 本身没有溶细胞活性，但据报道在细胞培养中具有促凋亡活性。在这里，我们报告了含有 OlyA6 高亲和力受体神经酰胺磷酸乙醇胺和胆固醇的脂质膜上 OlyA6 组装的形成动力学和结构。高速原子力显微镜揭示了 OlyA6 二聚体从初始随机表面覆盖到由六聚体 OlyA6 重复单元组成的 2D 蛋白晶体的重组。通过 OlyA6 二聚体的缔合，主要在纵向方向上发生晶体生长，形成六聚体单元晶胞。对 OlyA6 晶体的分子水平检查阐明了单元晶胞内二聚体的排列以及募集 pleurotolysin B 形成孔的二聚体的结构。
