Quantitifaction of the metabolic proteins that drive biogeochmical cycles in marine systems

驱动海洋系统生物地球化学循环的代谢蛋白的定量

基本信息

批准号：
NE/F019254/1
负责人：
Thomas Bibby
金额：
$ 29.16万
依托单位：
University of Southampton
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2009
资助国家：
英国
起止时间：
2009 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FF019254%2F1
关键词：
Quantitifaction metabolic proteins drive biogeochmical

项目摘要

In marine ecosystems, enzymes in microorganisms catalyse the chemical transformations of elemental cycles and stimulate energy flow though the ecosystem. It is both the abundance and efficiency of these enzymes that determine the rates of biochemical cycles in marine systems. These cycles shape our current and future global environments, and the ability to understanding and accurately model these cycles is therefore an important task for environmental scientists and a goal of the NERC mission statement. The daunting complexity of these marine microbial assemblages is only beginning to be understood. The size of the challenge is highlighted by programs such as the ambitious Global Ocean Sequencing Project (GOS) (http://www.jcvi.org/research/gos/), which, although only one-third complete, already represents the largest metagenomic dataset ever put into the public domain. Of more than 7.7 million sequences of DNA, 85% of the assembled sequence data is unique. This highlights that the marine microbial community remains unrepresented in laboratory culture collections and uncharacterized both genetically and biochemically. When we consider this complexity together with the fact that microorganisms are invisible to the naked eye, the challenge of accurately characterising the biochemical processes that have such a huge impact on our environment is particularly apparent. This project aims to develop techniques to complement these rate-based measurements and directly quantify the concentrations of key metabolic proteins irrespective of taxonomic origin in marine samples. The concentrations of these proteins limit the capacity of the biogeochemical process being studied and knowledge of changes in enzyme concentrations can further our understanding of the function of marine microbial communities. The techniques to be developed rely on the fact that the enzymes involved in biogeochemical cycles evolved very early in the Earth's history and, owing to their unique chemistry, have remained relatively unchanged over the evolution of life on Earth. Therefore, all microorganisms that are involved in biogeochemical cycles contain the same conserved enzymes, at the level of protein sequence, irrespective of taxonomy. As a result, established techniques for the quantification of specific proteins can yield valuable information on the abundance of the total amount of key metabolic enzymes in a sample isolated from complex marine systems. This approach benefits from the fact that micororganisms devote a large proportion of available energy and raw materials to the synthesis of these proteins, such that the enzyme complexes are often the major protein products within the cell and thereby represent abundant targets for quantification. This project aims to implement these technologies on the forthcoming Atlantic Medorial Transect (AMT) cruise planned for 2009, which will provide a platform from which samples can be collected on a north/south transect of the Atlantic and will provide the necessary ancillary data, including biological-rate measurements and microbial community structure. These techniques have the capacity to characterise and monitor the capacities of marine micororganisms to acclimate to anthropogenic rapid change in CO2, UV and nutrient cycling, and to map the distributions of these enzymes on a global scale.

在海洋生态系统中，微生物中的酶催化元素循环的化学转化并刺激生态系统的能量流动。这些酶的丰度和效率决定了海洋系统中生化循环的速率。这些循环塑造了我们当前和未来的全球环境，因此理解和准确建模这些循环的能力是环境科学家的一项重要任务，也是 NERC 使命宣言的目标。人们才刚刚开始了解这些海洋微生物组合的惊人复杂性。雄心勃勃的全球海洋测序项目 (GOS) (http://www.jcvi.org/research/gos/) 等计划凸显了挑战的规模，该项目虽然只完成了三分之一，但已经代表了最大的宏基因组数据集曾经进入公共领域。在超过 770 万条 DNA 序列中，85% 的组装序列数据是唯一的。这凸显出海洋微生物群落在实验室培养物保藏中仍然没有代表性，并且在遗传和生化方面都没有特征。当我们考虑到这种复杂性以及微生物肉眼看不见的事实时，准确描述对我们的环境产生巨大影响的生化过程的挑战就显得尤为明显。该项目旨在开发技术来补充这些基于速率的测量，并直接量化关键代谢蛋白的浓度，而不管海洋样本中的分类学起源。这些蛋白质的浓度限制了所研究的生物地球化学过程的能力，了解酶浓度的变化可以进一步我们对海洋微生物群落功能的理解。所开发的技术依赖于这样一个事实，即参与生物地球化学循环的酶在地球历史的早期就已经进化，并且由于其独特的化学性质，在地球生命的进化过程中保持相对不变。因此，无论分类学如何，参与生物地球化学循环的所有微生物在蛋白质序列水平上都含有相同的保守酶。因此，用于特定蛋白质定量的既定技术可以产生有关从复杂海洋系统分离的样品中关键代谢酶总量丰度的有价值的信息。这种方法受益于微生物将大部分可用能量和原材料用于合成这些蛋白质的事实，因此酶复合物通常是细胞内的主要蛋白质产物，从而代表了丰富的定量目标。该项目旨在在计划于 2009 年即将进行的大西洋中横断面 (AMT) 巡航中实施这些技术，该巡航将提供一个平台，可以在大西洋北/南横断面上采集样本，并提供必要的辅助数据，包括生物速率测量和微生物群落结构。这些技术能够表征和监测海洋微生物适应人为二氧化碳、紫外线和养分循环快速变化的能力，并绘制这些酶在全球范围内的分布图。