Collaborative Research: Microbial hydrogen oxidation at high pressure: Role of hydrogenases and interspecies hydrogen transfer

合作研究：高压微生物氢氧化：氢化酶和种间氢转移的作用

• 批准号: 1951673
• 负责人: Dionysios Foustoukos
• 金额: $ 22.86万
• 依托单位: Carnegie Institution of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1951673&HistoricalAwards=false
• 关键词: Collaborative; Research; Microbial; hydrogen; oxidation; Collaborative; Research; Microbial; hydrogen; oxidation

A large fraction of Earth’s microbial biosphere lives in the deep ocean and below the oceanic crust, under conditions of high hydrostatic pressures. However, very little is known about the contribution of these high-pressure adapted microbial communities to the Earth’s microbiome, their role in biogeochemical cycles, and their relevance for the evolution of early life on Earth. This project will investigate the adaptation mechanisms of high-pressure and high-temperature bacteria that use hydrogen as an energy source to different pressures and hydrogen concentration regimes. An innovative instrument for bacterial cultures at high pressure and temperature will be used to simulate the deep-sea physical (temperature, pressure) and chemical (hydrogen concentration) conditions. This experimental approach provides a unique opportunity to study microbial activity and functions by adjusting pressure conditions dynamically. Gene expression under different pressures and temperatures will also be monitored. Finally, since hydrogen oxidation is considered an ancient metabolic pathway, understanding hydrogen catabolism in these organisms may help to reconstruct the evolutionary history of early metabolism. The researchers will develop lessons and activities to translate the science for middle and high school aged learners. Lectures and lab demonstrations/tours will be delivered at George Mason University and Rutgers University to undergraduate/graduate students as part of graduate-level seminar series.Culture-based studies of the physiological and metabolic adaptations of high-pressure adapted bacteria are critical to advance understanding of microbial activity and bioenergetic adaptation strategies in deep-sea ecosystems. The main objective of this study is to explore the physiology and gene expression in high-pressure and high-temperature adapted bacteria (thermopiezophiles) that have been isolated from deep-sea hydrothermal vents. One of these bacteria, Nautilia strain PV-1, thrives at elevated pressure and at a temperature of 55°C, and can live off hydrogen gas and carbon dioxide. Experiments aimed at measuring gene and protein expression will be integrated with measurements of stable hydrogen isotope compositions to understand the combined effects of pressure and hydrogen concentration of the growth of thermopiezophiles. More specifically, this project will investigate the expression of the different hydrogenases of strain PV-1 in response to pressures up to 400 atmospheres, and to limiting and non-limiting concentration of hydrogen. Further, this project will investigate how elevated pressures affect the membrane structure of strain PV-1, which is important to maintain cellular integrity and to facilitate membrane trafficking. Finally, this project will investigate the transfer of hydrogen gas from a hydrogen-producing bacterium, Marinitoga piezophila, and the hydrogen consuming Nautilia strain PV-1.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.

在高静水压力的条件下，地球微生物生物圈的很大一部分生活在深海和海洋地壳下方。但是，对于这些高压适应的微生物群落对地球微生物组的贡献，它们在生物地球化学周期中的作用以及它们对地球早期生命进化的相关性，知之甚少。该项目将研究使用氢作为不同压力和氢浓度方案的能源的高压和高温细菌的适应机制。在高压和温度下细菌培养的创新仪器将用于模拟深海物理（温度，压力）和化学（氢浓度）条件。这种实验方法为研究微生物活性和功能提供了独特的机会，通过动态调节压力条件。在不同压力和温度下的基因表达也将受到监测。最后，由于氢氧化被认为是一种古老的代谢，因此了解这些生物体中的氢分解代谢可能有助于重建早期代谢的进化史。研究人员将开发课程和活动，以翻译中学和高中学习者的科学。演讲和实验室演示/旅行将在乔治·梅森大学和罗格斯大学提供本科/研究生，作为研究生级别的半身系列系列的一部分。基于培养的研究对高压适应细菌的生理和代谢适应性的研究至关重要，这对于促进对微生物活动和生物学适应策略的了解至关重要。这项研究的主要目的是探索在高压和高温适应细菌（热翼型）中的生理和基因表达，这些细菌已从深海热液通风孔中分离出来。这些细菌之一是Nautilia菌株PV-1，在升高的压力和55°C的温度下生长，可以在氢气和二氧化碳中生活。旨在测量基因和蛋白质表达的实验将与稳定氢同位素组成的测量集成，以了解热倍磷脂生长的压力和氢浓度的综合作用。更具体地说，该项目将研究菌株PV-1的不同氢化酶的表达，以响应高达400个大气的压力，并限制和非限制氢。此外，该项目将研究升高压力如何影响PV-1菌株的膜结构，这对于维持细胞完整性和促进膜运输很重要。最后，该项目将调查从产生氢的细菌，Marinitoga Piezophila和消耗Nautilia菌株PV-1的氢气转移的。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛影响的评估来审查的审查标准，通过评估来获得珍贵的支持。