Marine Biotech Fellowship: The Development and Use of Molecular Genetic Techniques for the Study of Fe Reduction in a Marine Eubacterium

海洋生物技术奖学金：分子遗传技术的开发和应用，用于研究海洋真细菌中的铁还原

• 批准号: 9212460
• 负责人: Joel Kostka
• 金额: $ 8.4万
• 依托单位: University of Wisconsin-Milwaukee
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-01-01 至 1994-09-23
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9212460&HistoricalAwards=false
• 关键词: Marine; Biotech; Fellowship; Development; Use

Physiological data suggest that a thermodynamic hierarchy for the utilization of oxidants could be written for Shewanella putrefaciens alone from aerobic growth in the oxic zone to thiosulfate reduction at the interface between sulfide-free and sulfitic zones of suboxic/anoxic marine basins and porewaters. With its versatile carbon metabolism and facultative nature, S. putrefaciens and organisms like it may well out compete sulfate- reducing bacteria for the consumption of thiosulfate and other sulfur intermediates in marine anoxic basins and sedimentary porewaters. These organisms may play a substantial role in the control of sulfur speciation in the marine environment. By utilizing organic carbon and producing sulfide, these organisms would be intimately involved in the poise of the chemocline. This project will provide new, basic scientific data on the molecular genetics of a widespread and very versatile anaerobic- respiring organism. By isolating and sequencing genes that code for sulfur reductase, this project will be able to study the regulatory mechanisms of gene expression. Manipulation of the genes in vivo will lead to a better understanding of the relationships between the various sulfur reduction pathways in S. putrefaciens and possibly other marine eubacteria. Genetic manipulation could also aid in comparing the regulation of sulfur reductase activity to that of nitrate reductase or Fe reductase in S. putrefaciens. This work will lead to the collaborative development of a probe for nonsulfate-reducing bacteria which utilize sulfur intermediates in natural sediments. Such a probe along with data on the mechanism of sulfur intermediate reduction could be used to explore the potential contribution of nonsulfate-reducing bacteria such as S. putrefaciens to the geochemistry of S, Fe, and C in a variety of suboxic/anoxic marine environments where these sulfur species exist.

生理数据表明，仅腐烂希万氏菌利用氧化剂的热力学等级可以从有氧区的有氧生长到亚缺氧/缺氧海洋盆地和孔隙水的无硫化物和硫酸盐交界处的硫代硫酸盐还原。腐败链霉菌及其类似的生物具有多功能性的碳代谢和兼性，在海洋缺氧盆地和沉积孔隙水中消耗硫代硫酸盐和其他硫中间体方面，可能会远远超过硫酸盐还原细菌。这些生物可能在控制海洋环境中硫的形态方面发挥重要作用。通过利用有机碳和产生硫化物，这些生物将密切参与趋化层的平衡。该项目将提供关于一种广泛且非常多样的厌氧呼吸有机体的分子遗传学的新的、基本的科学数据。通过分离和测序硫还原酶编码基因，该项目将能够研究基因表达的调控机制。在体内操纵这些基因将有助于更好地理解腐败链霉菌和其他海洋真细菌之间各种硫还原途径之间的关系。基因操作也有助于比较腐败链霉菌硫还原酶活性与硝酸还原酶或铁还原酶活性的调节。这项工作将导致合作开发一种非硫酸盐还原细菌的探针，该细菌利用天然沉积物中的硫中间体。这种探针结合硫中间体还原机理的数据，可以用来探索腐烂链球菌等非硫酸盐还原细菌在存在S、铁和碳的各种亚缺氧/缺氧海洋环境中对这些硫的地球化学的潜在贡献。