Metabolism of diazotrophic nitrogen fixing bacteria, insights from synthetic biology and metabolomics

固氮固氮细菌的代谢，合成生物学和代谢组学的见解

• 批准号: 1957804
• 金额: --
• 依托单位: Imperial College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1957804
• 关键词: Metabolism; diazotrophic; nitrogen; fixing; bacteria

One of the major limiting nutrients in crop growth is nitrogen. To tackle this, inorganic fertilisers are used to increase crop yield, however this comes at a high environmental cost. Biological nitrogen fixation, carried out by specialist bacteria, sees environmental dinitrogen converted into ammonia which is biologically available and presents an alternative, more environmentally friendly approach. This lab based project is focussed on understanding the metabolism of free living plant associative bacteria, particularly during the fixation process, by employing a range of synthetic biological techniques in conjunction with metabolomic approaches. Samples will be collected from a range of bacterial species and mutants and analysed using targeted and untargeted metabolomic methods, including Ultra High Performance Liquid Chromatography (UPLC-MS) and Nuclear Magnetic Resonance (NMR) spectroscopy. These complementary techniques allow for a better understanding of native fixation, and the effects it has on global metabolism. These findings will provide insights on how we might maximise the output of ammonia, and other secondary metabolites, to support increased crop growth and decrease inorganic fertiliser dependency. In addition, we aim to utilise our increased understanding of this process to inform future synthetic biological undertakings, for example generating new mutants or chimeric bacteria. Work will also be carried out investigating nutrient/chemical exchanges between bacteria and plant roots so that we can begin to see how this could work in real world contexts. Preliminary work has found that plants are able to utilise bacterially fixed nitrogen, with isotopically labelled nitrogen being found in their tissue.

氮是制约作物生长的主要养分之一。为了解决这个问题，人们使用无机肥料来提高作物产量，然而这需要付出高昂的环境代价。生物固氮是由专门的细菌进行的，它将环境中的二氮转化为生物上可用的氨，这是一种更环保的替代方法。这个实验室项目的重点是了解自由活的植物伴生细菌的代谢，特别是在固定过程中，通过采用一系列合成生物学技术与代谢组学方法相结合。将从一系列细菌物种和突变体中收集样本，并使用靶向和非靶向代谢组学方法进行分析，包括超高高效液相色谱（UPLC-MS）和核磁共振（NMR）光谱。这些互补的技术可以更好地理解自然固定及其对全球代谢的影响。这些发现将为我们如何最大限度地提高氨和其他次生代谢物的产量提供见解，以支持作物生长和减少对无机肥料的依赖。此外，我们的目标是利用我们对这一过程的进一步了解，为未来的合成生物学事业提供信息，例如产生新的突变体或嵌合细菌。我们还将研究细菌和植物根部之间的营养/化学交换，这样我们就可以开始看到这在现实世界中是如何起作用的。初步研究发现，植物能够利用细菌固定的氮，在它们的组织中发现了同位素标记的氮。