Greigite or magnetite: Environmental and genetic determinants controlling biomineralization in magnetotactic bacteria

镁铁矿或磁铁矿：控制趋磁细菌生物矿化的环境和遗传决定因素

• 批准号: 258774416
• 负责人: Dr. Damien Faivre
• 金额: --
• 依托单位: Laboratoire de Chimie Bactérienne
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/258774416?language=en
• 关键词: Greigite; magnetite; Environmental; genetic; determinants

There is a variety of materials formed by organisms, which often have superior properties than similar man-made materials, even if they are made with a limited amount of elements and under physiological conditions. Magnetosome chains in magnetotactic bacteria represent a biological paradigm of such a biological material, where magnetic nanocrystals with controlled properties are synthesized in organelles called magnetosomes and arranged into linear chains. These chains serve the cells to align along the Earth's magnetic field lines. The magnetosomes are made of a magnetite [Fe(II)Fe(III)2O4] or greigite [Fe(II)Fe(III)2S4] crystal embedded in a lipidic vesicle. Until recently, only magnetite-building strains were available in pure culture. Thus, the molecular and physico-chemical knowledge of the biomineralization mechanism steadily advanced in the recent years for those strains, but dramatically lags behind for greigite-mineralizing bacteria. With the isolation of a new type of cells, BW-1, we now have a model organism in our hands, which is able to form both magnetite and greigite. In this project, we thus propose an integrated and multidisciplinary approach to understand greigite biomineralization in magnetotactic bacteria. We will in particular study the environmental condition favoring the production of magnetite or greigite as well as the chemical reaction pathway leading to the formation of each magnetite and greigite in this BW-1 strain. In addition, we will determine what are the biological determinants involved in the biomineralization process with a particular focus on redox proteins such as the recently discovered magnetochrome. Finally, we will use this biological determinant in in vitro mineralization experiments to test their effect in biomimetic experiments. Our results will be of immediate relevance for the fundamental understanding of biomineralization in vivo. In addition, we anticipate our outcomes to be the starting point towards a more quantitative description of the role biological additives can have on the control of magnetic nanoparticles in the beaker.

生物体形成的材料多种多样，即使是在有限的元素含量和生理条件下形成的，也往往具有比同类人造材料优越的上级性能。趋磁细菌中的磁小体链代表了这种生物材料的生物范例，其中具有受控特性的磁性纳米晶体在称为磁小体的细胞器中合成并排列成线性链。这些链条使细胞沿着地球磁场线排列。磁小体是由磁铁矿[Fe（II）Fe（III）2 O 4]或硼硅矿[Fe（II）Fe（III）2S 4]晶体嵌入在一个囊泡中制成。直到最近，只有磁铁矿建设菌株可在纯培养。因此，近年来，这些菌株的生物矿化机制的分子和物理化学知识稳步推进，但显着落后于灰岩矿化细菌。随着一种新型细胞BW-1的分离，我们现在有了一种能够形成磁铁矿和硫铁矿的模式生物。因此，在这个项目中，我们提出了一个综合的和多学科的方法来了解在趋磁细菌的硼镁石生物矿化。我们将特别研究有利于产生磁铁矿或硼硅矿的环境条件，以及导致BW-1菌株中每种磁铁矿和硼硅矿形成的化学反应途径。此外，我们将确定生物矿化过程中涉及的生物决定因素，特别关注氧化还原蛋白，如最近发现的磁色素。最后，我们将此生物决定子应用于体外矿化实验，以测试其在仿生实验中的效果。我们的研究结果将是直接相关的基本了解生物矿化在体内。此外，我们预计我们的结果是一个更定量的描述生物添加剂的作用，可以在烧杯中的磁性纳米粒子的控制的起点。

项目成果

Controlled Biomineralization of Magnetite in Bacteria

• DOI: 10.1002/9783527691395.ch5
• 发表时间: 2016-04
• 作者: Elodie C. T. Descamps;J. Abbe;D. Pignol;C. Lefevre

Genomic study of a novel magnetotactic Alphaproteobacteria uncovers the multiple ancestry of magnetotaxis

• DOI: 10.1111/1462-2920.14364
• 发表时间: 2018-10
• 期刊: Environmental Microbiology
• 影响因子: 5.1
• 作者: C. Monteil;G. Perrière;N. Menguy;N. Ginet;Béatrice Alonso;Nicolas Waisbord;S. Cruveiller;D. Pignol

Accumulation and Dissolution of Magnetite Crystals in a Magnetically Responsive Ciliate

• DOI: 10.1128/aem.02865-17
• 发表时间: 2018-04-01
• 期刊: APPLIED AND ENVIRONMENTAL MICROBIOLOGY
• 影响因子: 4.4
• 作者: Monteil, Caroline L.;Menguy, Nicolas;Lefevre, Christopher T.
• 通讯作者: Lefevre, Christopher T.