Laboratory of Deep-Sea Microbial Cell Biology, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya 572000, China.
International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, CNRS-Marseille F-13402 France/ CAS-Sanya 572000, China.
Biomolecules. 2020 Mar 16;10(3):460. doi: 10.3390/biom10030460.
Marine environments are generally characterized by low bulk concentrations of nutrients that are susceptible to steady or intermittent motion driven by currents and local turbulence. Marine bacteria have therefore developed strategies, such as very fast-swimming and the exploitation of multiple directional sensing-response systems in order to efficiently migrate towards favorable places in nutrient gradients. The magnetotactic bacteria (MTB) even utilize Earth's magnetic field to facilitate downward swimming into the oxic-anoxic interface, which is the most favorable place for their persistence and proliferation, in chemically stratified sediments or water columns. To ensure the desired flagella-propelled motility, marine MTBs have evolved an exquisite flagellar apparatus, and an extremely high number (tens of thousands) of flagella can be found on a single entity, displaying a complex polar, axial, bounce, and photosensitive magnetotactic behavior. In this review, we describe gene clusters, the flagellar apparatus architecture, and the swimming behavior of marine unicellular and multicellular magnetotactic bacteria. The physiological significance and mechanisms that govern these motions are discussed.
海洋环境通常具有较低的营养物总量浓度，这些营养物容易受到由海流和局部紊流驱动的稳定或间歇运动的影响。因此，海洋细菌已经开发出了一些策略，例如快速游动和利用多个方向感应-响应系统，以便能够有效地朝着营养物梯度中的有利位置迁移。趋磁细菌 (MTB) 甚至利用地球磁场来促进向下游游到化学分层沉积物或水柱中的好氧-缺氧界面，这是它们持续和增殖的最有利位置。为了确保所需的鞭毛驱动的运动性，海洋 MTB 已经进化出了一种精密的鞭毛装置，并且在单个实体上可以发现数量极多（数万）的鞭毛，表现出复杂的极性、轴向、反弹和感光磁运动行为。在这篇综述中，我们描述了海洋单细胞和多细胞趋磁细菌的基因簇、鞭毛装置结构和游动行为。讨论了这些运动的生理意义和控制机制。
