ESCAPE 2.0: Establishing a scalable bioprocess reactor platform for cathodic obligate anaerobic electrobiosynthesis

微生物电合成（MES）允许利用电力，即电子，作为微生物生产化学品的反应物。由于具有自养生物过程的潜力，特别是阴极MES的严格厌氧微生物（也称为电自养微生物）在过去十年中引起了极大的研究兴趣。到目前为止，研究的重点仍然是微生物催化剂和可能的生物生产途径和产品的研究。然而，MES没有建立共同的生物过程基础设施，并且使用了各种各样的反应器，无法进行比较。在大多数实验室规模的系统中，生理应激源，例如来自阳极的氧气释放，会导致有害影响，从而降低MES性能。因此，迫切需要一个功能性和可扩展的生物过程基础设施，为MES的工业实施铺平道路。因此，ESCAPE 2.0项目（为阴极专性厌氧电生物合成建立一个可扩展的生物工艺反应器平台-项目2.0阶段）的目标是利用在第一个资助阶段获得的关于电自养梭菌ljungdahi生理应激的知识，开发一个多功能和可扩展的电生物反应器，用于高性能MES。为了进行这项研究，合作伙伴香港大学和UFZ建立在他们在微生物电化学和技术方面的共同卓越基础上。因此，ESCAPE 2.0分为两个联合工作包和每个合作伙伴的三个单独工作包。主干形成了反应器特异性和反应特异性性能参数和指标的连续镜像，建立了电生物反应器平台，为电自养生物MES提供了广阔的工艺窗口。ljungdahlii作为一种典型的氧气和有前途的厌氧生物生产平台，将作为电自养生物的例子。研究人员将对该催化剂进行深入的生理应力表征，随后将开发特定的生物传感器，并通过合理设计的分子和工艺工程扩大永达丽拟虫的产品范围。组件（如电极反应）以及结构（如chicanes或气体回收）的电生物反应器将设计和工程结合建模和实验为基础的方法。电生物反应器将使用电自养模型进行基准测试，包括全碳和电子平衡。最后，ESCAPE 2.0将导致1-L甚至高达3-L规模的电生物反应器，允许在不同的操作模式（例如批处理或流模式）下操作和深度生理表征严格厌氧MES。最终的电生物反应器也将与其他电养生物一起进行测试，并将提供给SPP财团的其他合作伙伴。

Microbial electrosynthesis (MES) allows utilizing electric power, hence electrons, as reactants for the microbial production of chemicals. With their potential for autotrophic bioprocesses, especially strict anaerobic microorganisms for cathodic MES (also known as electroautotrophs) have attracted significant research interest in the last decade. To date, the focus still is on the investigation of the microbial catalyst and possible bioproduction routes and products. However, for MES no common bioprocess infrastructure is established and a wide variety of reactors that allow no comparison is used. In most lab scale systems, physiological stressors, e.g. from oxygen evolving at the anode, lead to detrimental effects and hence a lower MES performance. Therefore, a functional and scalable bioprocess infrastructure is urgently needed for paving the way of MES to industrial implementation. Consequently, the goal of the project ESCAPE 2.0 (Establishing a scalable bioprocess reactor platform for cathodic obligate anaerobic electrobiosynthesis – project phase 2.0) is to work with the knowledge gained during the first funding phase on the physiological stress of the electroautotroph Clostridium ljungdahlii and develop a versatile and scalable electrobioreactor for high performance MES. For conducting this research, partners HKI and UFZ build on their shared excellent foundation on microbial electrochemistry and technology. Thereby, ESCAPE 2.0 is divided into two joint work packages and three individual work packages for each partner. The backbone forms the continuous mirroring of reactor-specific and reaction-specific performance parameters and indicators to allow establishing an electrobioreactor platform that provides a wide process window for MES by electroautotrophs. C. ljungdahlii – as a model acetogen and a promising anaerobic bioproduction platform – will serve as a example electroautotroph. A deep physiological stress characterization of the catalyst will be performed followed by the development of specific biosensors, as well as an expansion in C. ljungdahlii product profile via rational-designed molecular and process engineering. Components (e.g. electrode reactions) as well as architecture (e.g. chicanes or gas-recycling) of electrobioreactors will be designed and engineered in a combined modelling- and experimental-based approach. The electrobioreactors will be benchmarked using the model electroautotroph including full carbon and electron balances. Finally, ESCAPE 2.0 will lead to electrobioreactors at 1-L or even up to 3-L scale that allow the operation and deep physiological characterization of strictly anaerobic MES at different modes of operation (e.g. batch or flow-mode). The final electrobioreactors will also be tested with other electrotrophs and will be made available for other partners from the SPP consortium.