The ability of magnetotactic bacteria (MTB) to orient in magnetic fields is based on the synthesis of magnetosomes, which are unique prokaryotic organelles comprising membrane-enveloped, nano-sized crystals of a magnetic iron mineral that are aligned in well-ordered intracellular chains. Magnetosome crystals have species-specific morphologies, sizes, and arrangements. The magnetosome membrane, which originates from the cytoplasmic membrane by invagination, represents a distinct subcellular compartment and has a unique biochemical composition. The roughly 20 magnetosome-specific proteins have functions in vesicle formation, magnetosomal iron transport, and the control of crystallization and intracellular arrangement of magnetite particles. The assembly of magnetosome chains is under genetic control and involves the action of an acidic protein that links magnetosomes to a novel cytoskeletal structure, presumably formed by a specific actin-like protein. A total of 28 conserved genes present in various magnetic bacteria were identified to be specifically associated with the magnetotactic phenotype, most of which are located in the genomic magnetosome island. The unique properties of magnetosomes attracted broad interdisciplinary interest, and MTB have recently emerged as a model to study prokaryotic organelle formation and evolution.

中文翻译：

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趋磁细菌中磁小体形成的遗传学和细胞生物学。

趋磁细菌（MTB）在磁场中定向的能力是基于磁小体的合成，磁小体是独特的原核细胞器，其包含膜包裹的磁性铁矿物质的纳米尺寸晶体，排列在排列整齐的细胞内链中。磁小体晶体具有特定于物种的形态，大小和排列。磁小体膜通过内在起源于细胞质膜，代表一个独特的亚细胞区室，并具有独特的生化成分。大约20种磁小体特异性蛋白在囊泡形成，磁小体铁运输以及控制磁铁矿颗粒的结晶和细胞内排列方面具有功能。磁小体链的组装处于遗传控制之下，并且涉及一种酸性蛋白的作用，该酸性蛋白将磁小体链接到新的细胞骨架结构，该结构可能由特定的肌动蛋白样蛋白形成。鉴定出存在于各种磁性细菌中的总共28个保守基因与趋磁表型特异性相关，其中大多数位于基因组磁小体岛中。磁小体的独特性质吸引了广泛的跨学科兴趣，并且MTB最近已成为研究原核细胞器形成和进化的模型。其中大多数位于基因组磁小体岛。磁小体的独特性质吸引了广泛的跨学科兴趣，并且MTB最近已成为研究原核细胞器形成和进化的模型。其中大多数位于基因组磁小体岛。磁小体的独特性质吸引了广泛的跨学科兴趣，并且MTB最近已成为研究原核细胞器形成和进化的模型。