Dissertation Research: Do the concomitant effects of pH and ammonium concentration on ammonia availability explain differential ammonia oxidation by bacteria and archaea?

论文研究：pH 值和铵浓度对氨利用率的共同影响是否可以解释细菌和古细菌对氨的氧化差异？

• 批准号: 1210607
• 负责人: John Barrett
• 金额: $ 1.5万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1210607&HistoricalAwards=false
• 关键词: Dissertation; Research; Do; concomitant; effects

Ammonia oxidation, a key step in the global nitrogen cycle, is only known to be performed by two groups of microorganisms, ammonia oxidizing bacteria and archaea. Although these groups both occur in large numbers in soil environments, they, like many microorganisms, may only be active under certain conditions. This study will investigate how environmental conditions interact to control the activity of ammonia oxidizing bacteria and archaea. Soil samples will be exposed to different environmental conditions and the activity of ammonia oxidizing bacteria and archaea will be measured using molecular based techniques. Experimental treatments will include variation in ammonium concentrations and soil pH, both of which have been shown to individually alter the activity of cultured representatives from these two groups. Use of naturally occurring populations of soil microorganisms will lend field relevance to these culture-based observations, and should lead to a better understanding of nitrification by investigating the ecology of the organisms that perform this important nutrient transformation in the nitrogen cycle.Broader impacts of this project will include an additional research opportunity for the doctoral student. In addition, undergraduate students will be involved in various aspects of this project, providing them with exposure to research and opportunities to develop their own independent research projects.

氨氧化是全球氮循环中的关键步骤，目前已知仅由两类微生物进行，即氨氧化细菌和古细菌。虽然这两种微生物都大量存在于土壤环境中，但它们和许多微生物一样，可能只在某些条件下才有活性。本研究将探讨环境条件如何相互作用，以控制氨氧化细菌和古细菌的活动。土壤样品将暴露于不同的环境条件下，氨氧化细菌和古细菌的活性将使用基于分子的技术进行测量。实验处理将包括铵浓度和土壤pH值的变化，这两者都已被证明可以单独改变这两组培养代表的活性。利用自然发生的土壤微生物种群将使这些基于培养的观察具有现场相关性，并通过调查在氮循环中进行这一重要营养转化的生物体的生态学，更好地了解硝化作用。此外，本科生将参与该项目的各个方面，为他们提供接触研究和发展自己的独立研究项目的机会。