Novel electron transfer pathways in Ralstonia eutropha

富养罗尔斯顿菌中的新型电子传递途径

• 批准号: 445867394
• 负责人: Professor Dr.-Ing. Dirk Holtmann
• 金额: --
• 依托单位: Arbeitsgruppe Physikalische Chemie/ Biophysikalische Chemie
• 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/445867394?language=en
• 关键词: Novel; electron; transfer; pathways; Ralstonia

The well-characterized Gram-negative bacterium Ralstonia eutropha is capable in utilizing a wide array of heterotrophic carbon sources, but it is renowned for its ability to fix CO2 under chemolithoautotrophic conditions. Due to its flexible metabolism and the increasing availability of tools for its genetic engineering, it receives rapidly growing interest for biotechnological application. In fact, metabolically engineered R. eutropha strains have already been shown to produce various chemicals and biopolymers under autotrophic conditions. Nevertheless, upscaling of H2/O2-based autotrophic cultivation is risky due to potential formation of explosive gas mixtures (oxyhydrogen, “Knallgas”), which results in rigorous safety requirements. Furthermore, the CO2 fixation efficiency is lower in the presence of O2, due to an oxygenase side reaction of the CO2-fixing enzyme RuBisCO. These issues can be circumvented by the use of alternative electron acceptors substituting O2. In this proposal, a bioelectrochemical system (BES) will be investigated with regard to its use as an extracellular electron acceptor. Furthermore, reversibility of the novel electron transfer systems will be explored for their potential to be exploited in cathode-driven electrosynthesis approaches. In this the project, the expertise of the Lenz/Frielingsdorf group (microbiology, molecular biology and biochemistry of R. eutropha) and the Holtmann group (biochemical and electrochemical engineering, electrobiotechnological production processes with R. eutropha) will be combined to connect the cellular redox metabolism of R. eutropha with suitable electrodes to establish a novel, safe, versatile, and highly efficient production platform.

特征明确的革兰氏阴性细菌富养罗尔斯通氏菌能够利用多种异养碳源，但它以其在化能自养条件下固定二氧化碳的能力而闻名。由于其灵活的新陈代谢和基因工程工具的不断增加，它受到生物技术应用的兴趣迅速增长。事实上，代谢工程改造的富养罗伯茨菌菌株已被证明可以在自养条件下产生各种化学物质和生物聚合物。然而，由于可能形成爆炸性气体混合物（氢氧气，“Knallgas”），基于 H2/O2 的自养培养规模的扩大是有风险的，这导致了严格的安全要求。此外，由于 CO2 固定酶 RuBisCO 的加氧酶副反应，在 O2 存在的情况下，CO2 固定效率较低。通过使用替代 O2 的替代电子受体可以避免这些问题。在该提案中，将研究生物电化学系统（BES）作为细胞外电子受体的用途。此外，还将探索新型电子转移系统的可逆性，以了解其在阴极驱动电合成方法中的潜力。在该项目中，Lenz/Frielingsdorf小组（富养罗尔斯通氏菌的微生物学、分子生物学和生物化学）和Holtmann小组（生化和电化学工程、富养罗尔斯通氏菌的电生物技术生产工艺）的专业知识将结合起来，将富养罗尔斯通氏菌的细胞氧化还原代谢与合适的电极连接起来，以建立一种新颖的、 安全、多功能、高效的生产平台。