Collaborative Research: Unravelling mechanisms of Fe oxidation using syntheic biology and biochemistry

合作研究：利用合成生物学和生物化学揭示铁氧化机制

• 批准号: 1817651
• 负责人: Clara Chan
• 金额: $ 50万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1817651&HistoricalAwards=false
• 关键词: Collaborative; Research; Unravelling; mechanisms; Fe

Iron-oxidizing bacteria (FeOB) take advantage of Earth's abundant iron for growth. They form iron oxides or rust that sequester toxic metals and nutrients. By understanding how these microbes use iron in the environment and developing tools to domesticate them, it would be possible to harness this power for bioremediation of water, wastewater, and sediment. This research would develop the ability to monitor iron oxidation in natural and engineered systems, and furthermore optimize the process using in situ or engineered organisms. This project will educate a diverse population in microbiology, biochemistry, and synthetic biology, to develop scientific creative skills and help prepare them to use microbiology to address environmental and biotechnical challenges. Outreach activities include a "Making microbes work for us!" workshop for girls in middle school, who are first-generation college-bound students, and a range of public lectures, town halls, videos, and podcasts. The overarching message is that microbes are useful, integral parts of ecosystems, which can be harnessed to meet environmental and societal needs. This project focuses on two putative iron (Fe) oxidase systems, outer membrane cytochrome-porins Cyc2 and MtoAB, from neutrophilic FeOB. The objective is to validate the Fe oxidation activity and determine differences in function, providing information required for applying these Fe oxidases in synthetic systems. Thus, the project aims are to demonstrate and characterize Fe(II) oxidation by purified Cyc2 and MtoAB; express Fe oxidases Cyc2 and MtoAB in an engineered Shewanella oneidensis chassis strain to compare and optimize function in an environmentally-relevant strain; and develop genetic tools in neutrophilic autotrophic FeOB using synthetic biology. The Fe oxidase Cyc2 and MtoAB sequences will be taken from a common freshwater FeOB, Sideroxydans lithotrophicus ES-1, heterologously expressed, and characterized for redox potential and activity under a range of environmentally-relevant conditions. In addition, a novel chassis organism, Shewanella oneidensis, will be engineered to express Cyc2 and MtoAB, then assayed for Fe oxidation activity under various conditions. In parallel, the project will also develop tools and methods to domesticate FeOB. Development of these genetic systems will enable this and other research groups to query and verify otherwise recalcitrant pathways. This work will substantiate Fe oxidase function of Cyc2 and MtoAB, and provide insight into the biochemical mechanisms and the optimal conditions of function.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

铁氧化细菌（FeOB）利用地球丰富的铁来生长。它们形成铁氧化物或铁锈，隔离有毒金属和营养物质。通过了解这些微生物如何利用环境中的铁并开发驯化它们的工具，就有可能利用这种能力对水、废水和沉积物进行生物修复。这项研究将开发监测自然和工程系统中铁氧化的能力，并进一步优化使用原位或工程生物体的过程。该项目将对不同人群进行微生物学、生物化学和合成生物学方面的教育，培养科学创新技能，并帮助他们做好利用微生物学应对环境和生物技术挑战的准备。外展活动包括“让微生物为我们工作！”为初中女生（第一代即将上大学的学生）举办的讲习班，以及一系列公共讲座、市政厅、视频和播客。最重要的信息是，微生物是生态系统中有用的、不可或缺的一部分，可以利用微生物来满足环境和社会需求。该项目重点研究来自中性粒细胞 FeOB 的两种假定的铁 (Fe) 氧化酶系统：外膜细胞色素孔蛋白 Cyc2 和 MtoAB。目的是验证铁氧化活性并确定功能差异，提供在合成系统中应用这些铁氧化酶所需的信息。因此，该项目的目标是演示和表征纯化的 Cyc2 和 MtoAB 的 Fe(II) 氧化作用；在工程化的 Shewanella oneidensis 底盘菌株中表达 Fe 氧化酶 Cyc2 和 MtoAB，以比较和优化环境相关菌株的功能；并利用合成生物学开发中性粒细胞自养 FeOB 的遗传工具。 Fe 氧化酶 Cyc2 和 MtoAB 序列取自常见的淡水 FeOB（Sideroxydans lithotropicus ES-1），异源表达，并在一系列环境相关条件下表征氧化还原电位和活性。此外，一种新型底盘生物 Shewanella oneidensis 将被设计来表达 Cyc2 和 MtoAB，然后在各种条件下测定 Fe 氧化活性。与此同时，该项目还将开发驯化 FeOB 的工具和方法。这些遗传系统的开发将使该研究小组和其他研究小组能够查询和验证其他顽固的途径。这项工作将证实 Cyc2 和 MtoAB 的 Fe 氧化酶功能，并提供对生化机制和最佳功能条件的深入了解。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查进行评估，被认为值得支持标准。

项目成果

Iron Oxidation by a Fused Cytochrome-Porin Common to Diverse Iron-Oxidizing Bacteria

多种铁氧化细菌常见的融合细胞色素孔蛋白对铁的氧化

• DOI: 10.1128/mbio.01074-21
• 发表时间: 2021-01
• 期刊: mBio
• 影响因子: 6.4
• 作者: Keffer, Jessica L.;McAllister, Sean M.;Garber, Arkadiy I.;Hallahan, Beverly J.;Sutherland, Molly C.;Rozovsky, Sharon;Chan, Clara S.
• 通讯作者: Chan, Clara S.

Biological Oxidation of Fe(II)-Bearing Smectite by Microaerophilic Iron Oxidizer Sideroxydans lithotrophicus Using Dual Mto and Cyc2 Iron Oxidation Pathways

• DOI: 10.1021/acs.est.2c05142
• 发表时间: 2022-12-06
• 期刊: Environmental Science & Technology
• 影响因子: 11.4
• 作者: Zhou, Nanqing;Kupper, Robert J.;Catalano, Jeffrey G.;Thompson, Aaron;Chan, Clara S.
• 通讯作者: Chan, Clara S.

Gallionellaceae pangenomic analysis reveals insight into phylogeny, metabolic flexibility, and iron oxidation mechanisms

Gallionellaceae 全基因组分析揭示了系统发育、代谢灵活性和铁氧化机制的见解

• DOI: 10.1128/msystems.00038-23
• 发表时间: 2023-12-21
• 期刊: mSystems
• 影响因子: 6.4
• 作者: Hoover, Rene L.;Keffer, Jessica L.;Polson, Shawn W.;Chan, Clara S.
• 通讯作者: Chan, Clara S.