Systems metabolic engineering of Hydrogenophaga pseudoflava for aerobic biosynthesis of fatty acids using CO2 and electron carriers in a novel bioelectrochemical system

在新型生物电化学系统中使用 CO2 和电子载体进行脂肪酸有氧生物合成的 Hydrogenophaga pseudoflava 系统代谢工程

• 批准号: 445541534
• 负责人: Professor Dr. Bastian Blombach
• 金额: --
• 依托单位: Institut für Bioprozess- und Biosystemtechnik V-1
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/445541534?language=en
• 关键词: Systems; metabolic; engineering; Hydrogenophaga; pseudoflava

Electrobiotechnology is a promising technology at the interface of electrochemistry and biotechnology to use CO2 and electricity for the microbial biosynthesis of chemicals and fuels in bioelectrochemical systems (BES). An appealing approach in this regard is the conversion of CO2 to CO and the formation of syngas (H2, CO, CO2) electrochemically; the latter is then biologically converted into chemicals or liquid fuels. Although the decoupled bioconversion of syngas has made impressive progresses recently, this technology still has several inherent obstacles such as limited mass transfer of gases into culture medium, low uptake or inefficient transfer of electrons or electron carriers to the microbial host, and safety issues regarding toxicity and explosiveness of the substrates. Furthermore, acetogens as the mostly used microbial hosts for syngas bioconversion have a limited spectrum of products since the production of more complex molecules is outside the metabolic capacity. In this project, the great potential of Hydrogenophaga pseudoflava in the aerobic utilization of syngas and the capacity of engineered H. pseudoflava for the production of fatty acids will be explored in a novel direct electromicrobial production system with in situ and on demand production of H2 and O2 (from water) and CO (from CO2). To develop a systemic and quantitative understanding of the electron transfer and its impact on redox and energy metabolism of this carboxydotrophic bacterium, we will apply metabolomics, flux analysis and quantify kinetic parameters of the wild type and engineered mutants defective in electron transfer, energy and redox metabolism under given gas compositions provided by an optimized BES. The BES will address current limitations of bio-electrochemical systems and gas fermentations as already mentioned above. The gained knowledge will be utilized to set up a first metabolic and electron transfer model of the autotrophic metabolism of H. pseudoflava, especially regarding uptake of the different electron carriers, energy and redox balances. Furthermore, we will engineer H. pseudoflava for the production of fatty acids which represent an ATP and NADPH intensive product class and therefore its overproduction will challenge the metabolism of H. pseudoflava especially under autotrophic conditions. A quantitative analysis of the developed strains will be used to evaluate and refine the metabolic and electron transfer model. This project will open up new possibilities to engineer efficient electromicrobial production strains and to develop improved electro-fermentation.

电生物技术是电化学与生物技术相结合的一种很有前途的技术，它利用二氧化碳和电能在生物电化学系统中进行化学物质和燃料的微生物生物合成。在这方面，一个吸引人的方法是将CO2转化为CO并形成合成气（H2， CO, CO2）电化学；后者然后被生物转化为化学品或液体燃料。虽然合成气的解耦生物转化近年来取得了令人瞩目的进展，但该技术仍然存在一些固有的障碍，如气体向培养基中的传质有限，电子或电子载体向微生物宿主的吸收低或转移效率低，以及底物的毒性和爆炸性等安全问题。此外，作为合成气生物转化最常用的微生物宿主，醋酸菌的产物谱有限，因为更复杂分子的产生超出了代谢能力。在这个项目中，将在一个新的直接电微生物生产系统中探索假黄食氢菌在合成气好氧利用方面的巨大潜力，以及工程假黄食氢菌生产脂肪酸的能力，该系统可以就地和按需生产H2和O2（从水）和CO（从CO2）。为了对这种羧营养细菌的电子转移及其对氧化还原和能量代谢的影响有一个系统和定量的了解，我们将应用代谢组学、通量分析和量化在电子转移、能量和氧化还原代谢方面有缺陷的野生型和工程突变体在优化的BES提供的给定气体组成下的动力学参数。如上所述，BES将解决目前生物电化学系统和气体发酵的局限性。利用所获得的知识建立假黄豆自养代谢的第一个代谢和电子传递模型，特别是关于不同电子载体的吸收、能量和氧化还原平衡。此外，我们将设计假黄毒杆菌生产脂肪酸，代表ATP和NADPH密集型产品类别，因此其过量生产将挑战假黄毒杆菌的代谢，特别是在自养条件下。开发菌株的定量分析将用于评估和完善代谢和电子转移模型。该项目将为设计高效的电微生物生产菌株和开发改进的电发酵开辟新的可能性。