趋磁细菌中的磁接收器

Magnetite magnetoreception in magnetotactic bacteria

趋磁细菌是一种水生的能够运动的微生物,通常存在于含氧—缺氧的具有垂直化学梯度的沉积物和水柱等过渡区域中.在这种分层环境中,地磁场磁力线作为垂直通道,趋磁细菌在通道中沿着磁力线方向排列,上下运动寻找最佳生存位置.这种现象背后的机制则是趋磁细菌体内磁小体磁接收器的存在.趋磁细菌体内具有磁性的链状排列的磁小体,磁小体链与外磁场相互作用,使趋磁细菌可以沿着磁力线游动,具有极性趋磁性,而这种趋磁性与趋磁细菌趋氧性密切相关,帮助它处于最佳氧化还原生存环境中.本文就主要对趋磁细菌体内的磁小体、磁小体链的物理特征以及磁小体磁接收器的工作模型做简要描述,希望能为相关研究提供借鉴.

Magnetotactic bacteria is microorganism which can move and exist in the sediment and water column with vertical chemical gradient from oxygen to hypoxia.In these layered environments,magnetic lines of geomagnetic field can be as vertical channel,magnetotactic bacteria can arrange along the magnetic line and swim to searching the best living position.The magnetosome magnetoreception in magnetotactic bacteria is the foundation of all these phenomenon.In magnetotactic bacteria,there exist magnetic magnetosomes arranging in line which interact with external magnetic field and make magnetotactic bacteria swim along the magnetic lines and have polar magnetotaxis.However,the polar magnetotaxis is closely related to the oxygenotaxis of magnetotactic bacteria which help magnetotactic bacteria seek the best position to satisfy their nutritional requirement.In this paper,the physical characteristics of magnetosome and magnetosome chain in magnetotactic bacteria and the working model of magnetosome magnetoreception are briefly descripted for providing reference for relevant research.