Respiration-linked Metal Reduction in Bacteria

细菌中与呼吸相关的金属还原

• 批准号: 9017525
• 负责人: Charles Myers
• 金额: $ 20万
• 依托单位: South Dakota State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-09-15 至 1994-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9017525&HistoricalAwards=false
• 关键词: Respiration; linked; Metal; Reduction; Bacteria

Microbes that can couple their anaerobic growth to the reduction of manganese(IV) and iron(III) have only recently been isolated and make it possible to investigate the physiology and biochemistry of the microbial processes responsible for the use of manganese(IV) and iron(III) as terminal electron acceptor for anaerobic respiration. These microbes may act as important biogeochemical agents for the cycling of these metals in aquatic and soil environments. The more immediate objectives of this project include the study of one such microbe, Shewanella (formerly Alteromonas) putrefaciens strain MR-1, including: (1) determination of the growth energetics when growth is coupled to the reduction of manganese or iron, and comparison of these energetics to those involving the use of other electron acceptors(O2, nitrate, and fumarate); (2) determination and preliminary characterization of the electron transport components involved in the respiratory reduction of these metals; and (3) purification and characterization the terminal reductases responsible for the reduction of these metals. Several aspects of this work form the foundation for its scientific rationale. First, the ability of certain bacteria to couple their growth to the dissolution of manganese and iron oxides represents a novel form of bacterial metabolism; this project uncovers aspects of bacterial physiology and biochemistry heretofore unknown. Gaining insight into these mechanisms broadens the current state of knowledge concerning anaerobic (i.e. oxygen-free) respiration, knowledge which is currently limited to studies of only a few bacteria. Such versatility makes this bacterium a valuable model for studying the components and regulation of oxygen-free respiration. Thirdly, as this bacterium could make a significant contribution to the cycling of manganese and iron in aquatic sediments and flooded soils, knowledge of its mechanisms of metal reduction enhances our understanding of the roles of metal-reducing bacteria in the environment. Overall, the studies lead to new ways of thinking about oxygen-free respiration, as well as the environmental cycling of certain metals.

微生物可以将其厌氧生长与还原反应结合起来， 锰（IV）和铁（III）的化合物最近才被分离出来 使研究生理学成为可能， 生物化学的微生物过程负责使用 锰（IV）和铁（III）作为末端电子受体， 无氧呼吸 这些微生物可能扮演着重要的角色 这些金属在水生物中循环的生物地球化学因子 土壤环境。 更直接的目标是 一个项目包括对其中一种微生物希瓦氏菌的研究 （以前称为Alteromonas）putrefaciens菌株MR-1，包括：（1） 当生长耦合到 锰或铁的还原及其比较 涉及使用其他电子的能量学 受体（O2、硝酸盐和富马酸盐）;（2）测定和 电子传递组分的初步表征 参与这些金属的呼吸还原;以及（3） 末端还原酶的纯化和性质 负责这些金属的还原。 这项工作的几个方面构成了其基础 科学理性。 首先，某些细菌的能力， 将它们的生长与锰和铁的溶解结合起来 氧化物代表了细菌代谢的一种新形式;这 该项目揭示了细菌生理学和生物化学的各个方面 迄今未知。 深入了解这些机制 拓宽了目前关于厌氧的知识 (i.e.无氧）呼吸，目前 仅限于对少数细菌的研究。 如此多才多艺 使得这种细菌成为研究 和无氧呼吸的调节。 第三，作为 细菌可以对循环做出重大贡献。 水生沉积物和淹水土壤中的锰和铁， 了解其金属还原机制， 了解金属还原菌在 环境 总的来说，这些研究带来了新的思维方式 关于无氧呼吸，以及环境 某些金属的循环。