Structure of Magnetosomes from Magnetospirillum gryphiswaldense

Aim of this proposal is to study the structure of magnetosomes, which are chains of iron oxide (Fe3O4) nanoparticles that we are able to extract and purify from Magnetospirillum gryphiswaldense bacteria. Magnetosomes are of significant interest as tools for delivery drugs to a targeted area because of their small size, ferromagnetic properties and presence of membrane proteins embedded in the lipid bilayer that covers the surface of the iron oxide core. Structural information regarding core and layer dimensions as well as layer composition and number of magnetosome units per chain will be obtained with contrast variation SANS experiments that we plan to perform on samples obtained by bacteria that have been grown under a wide range of controlled conditions.

本提案旨在研究磁小体（magnetosomes）的结构——这类结构是可从格里菲斯瓦尔德磁螺菌（*Magnetospirillum gryphiswaldense*）中提取并纯化的氧化铁（Fe₃O₄）纳米颗粒链。磁小体因其尺寸微小、铁磁特性，以及覆盖于氧化铁核心表面的脂质双分子层中嵌有膜蛋白等优势，作为靶向药物递送工具受到广泛关注。我们计划对在多种受控条件下培养的细菌样本开展对比变异小角中子散射（SANS）实验，以获取磁小体核心与层的尺寸、层组成及每条链中磁小体单元数量等关键结构信息。