摘要
综述了近年趋磁细菌纳米磁小体生物合成的分子机制及应用进展。磁小体的合成涉及磁小体膜的形成、铁的吸收和转运、磁小体晶体的矿化、成熟以及磁小体的链状排列等。其中Mam J和Mam K互作并丝状排列,固定磁小体使其链状排列及磁小体膜由细胞质膜内陷而形成是两个令人注目的成就。我们也提出了关于磁小体的生理意义及合成机制的假说:细胞在低氧浓度下由于氧胁迫大量吸收铁,Fe3+/Fe2+电子对可起到类似O2/H2O的作用,产生能量并作为电子受体;Fe3+得到电子还原成的Fe2+可引起Fenton反应,此反应产生的活性氧可影响到生物体的正常生理代谢,细胞为降低Fe2+浓度,将其与Fe3+一同转化为Fe3O4颗粒;磁小体的生理功能之一是降低胞内的活性氧。
We reviewed the progress of magnetosomes biosynthesis mechanism and its application.Magnetosomes formation is involved in magnetosomes＇ membrane formation,iron absorption and transport,magnetic crystals biomineralization and magentosomes＇ chain-like assembly,etc.In the past decade,two remarkable achievements have been realized,one is that magnetosome vesicles are invaginations from plasma membranes,and the other is that MamK as magnetosomes filament interacts with MamJ resulting in maintanance of magnetosomes queue to chain in cells.We suggested that the Fe3＋/Fe2＋ couple act as O2/H2O capture electronic to generate energy and form Fe3O4 to eliminate reactive oxygen species（ROS） produced by Fenton reaction under low oxygen and high iron stress conditions.One of roles of the magnetosomes is to reduce the intracellular ROS.
出处
《生物技术进展》
2012年第1期16-22,F0003,共8页
Current Biotechnology
基金
中央高校基本科研业务费专项资金(KYCX2011024)
国家自然科学基金项目(31170089)资助
关键词
趋磁细菌
磁小体
生物矿化
自由基
magnetotactic bacteria
magnetosomes
biomineralization
reactive oxygen species
