Controlled formation of magnetite crystal by partial oxidation of ferrous hydroxide in the presence of recombinant magnetotactic bacterial protein Mms6
Controlled formation of magnetite crystal by partial oxidation of ferrous hydroxide in the presence of recombinant magnetotactic bacterial protein Mms6
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DOI：
10.1016/j.biomaterials.2007.07.051
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发表时间：
2007-12-01
期刊：
影响因子：
14
通讯作者：
Matsunaga, Tadashi
中科院分区：
文献类型：
--
作者：
Amemiya, Yosuke;Arakaki, Atsushi;Matsunaga, Tadashi
Mms 6是一种小的酸性蛋白质，与磁性细菌AMB-1中的细菌磁铁矿紧密相关。这种蛋白质以前已经显示出铁结合活性，使其能够通过亚铁和三价铁离子的共沉淀产生均匀的磁性晶体。在这里，磁铁矿晶体形成的部分氧化亚铁的氢氧化物在存在和不存在的MMS 6。使用高分辨率透射电子显微镜，根据它们的尺寸和形态，系统地表征合成的晶体。通过这种方法，Mms 6介导的磁铁矿合成产生了具有立方八面体形态的均匀尺寸和窄尺寸分布的晶体，类似于在M.磁性AMB-1在不存在Mms 6的情况下形成的晶体是八面体的，更大，具有增加的尺寸分布。合成颗粒中Mms 6的蛋白质定量分析表明该蛋白质与晶体紧密结合。此外，对铁离子的高亲和力和高度带电的静电性质表明，蛋白质作为核形成的模板和/或通过识别晶面作为生长调节剂。在这项研究中介绍的方法提出了一种替代路线，用于控制磁铁矿晶体的大小和形状，而不使用有机溶剂和高温。(C)2007爱思唯尔有限公司保留所有权利。
Mms6 is a small acidic protein that is tightly associated with bacterial magnetite in Magnetospirillum magneticum AMB-1. This protein has previously shown iron binding activity, allowing it to generate uniform magnetic crystals by co-precipitation of ferrous and ferric ions. Here, magnetite crystals were formed by the partial oxidation of ferrous hydroxide in the presence and absence of Mms6. The crystals synthesised were systematically characterised according to their sizes and morphologies using high-resolution transmission electron microscopy. Mms6-mediated synthesis of magnetite by this methods produced crystals of a uniform size and narrow size distribution with a cubo-octahedral morphology, similar to bacterial magnetite observed in M. magneticum AMB-1. The crystals formed in the absence of Mms6 were octahedral, larger with an increased size distribution. Protein quantification analysis of Mms6 in the synthesised particles indicated tight association of this protein onto the crystal. Furthermore, high affinities to iron ions and a highly charged electrostatic quality suggest that the protein acts as a template for the nucleus formation and/or acts as a growth regulator by recognising crystal faces. The method introduced in this study presents an alternative route for controlling the size and shape of magnetite crystals without the use of organic solvent and high temperatures. (C) 2007 Elsevier Ltd. All rights reserved.