Vibrio natriegens as novel workhorse for industrial biotechnology

工业发酵过程的生产率基本上受到微生物系统的生物量特定底物消耗率(QS)的限制。由于QS依赖于生长速度(伽马)，我们确定钠弧菌是未来生物技术过程中潜在的新型工作马。钠弧菌是地球上生长速度最快的非致病细菌。对该菌的初步研究证实，该菌在BHIN复合培养基上生长迅速，倍增时间为9.4分钟，并表明该菌能代谢多种工业相关底物。此外，钠弧菌在极低的葡萄糖浓度下均能好氧和厌氧生长，葡萄糖QS值分别为3.90±0.08gg-1h-1(好氧)和7.81±0.71gg-1h-1(厌氧)，均显著高于现有的微生物体系。此外，在厌氧条件下，静息细胞保持代谢活性(QS=1.02±0.05gg-1h-1)，发酵产物为乙酸盐、乳酸、琥珀酸、甲酸、丙氨酸和乙醇，体积产率(QP)在1.7g-4.3g L-1h-1之间。分泌产物的累积QP为17.7±0.1g L-1h-1。本项目的总体目标是建立钠弧菌作为工业生物技术的一个新的生产平台，并强调该菌未来工作的潜力。为了实现这一目标，需要建立相关工艺条件下的转录和代谢图谱，作为进一步应用转录组和代谢组分析进行代谢工程研究的基础。已有的分子生物学工具箱将首次应用于构建可用于好氧和厌氧生产L-缬氨酸和琥珀酸的钠弧菌。对于开发的菌株，将建立和优化在其性能数据方面优于现有文献描述的工艺的发酵工艺。

The productivity of industrial fermentation processes is essentially limited by the biomass-specific substrate consumption rate (qS) of the microbial system. Since the qS is dependent on the growth rate (gamma), we identified Vibrio natriegens as a potential novel workinghorse for future biotechnological processes. V. natriegens is the non-pathogenic bacterium with the highest growth rates on our planet. Preliminary work with this organism confirmed the rapid growth on BHIN complex medium with doubling times of 9.4 minutes and showed that V. natriegens can metabolize a variety of industrially relevant substrates. In addition, V. natriegens is growing both aerobically and anaerobically and shows in minimal medium with glucose exceptional high qS values of 3.90 ± 0.08 g g-1 h-1 (aerobic) and 7.81 ± 0.71 g g-1 h-1 (anaerobic), which are significantly higher than those of established microbial systems. In addition, resting cells under anaerobic conditions remained metabolically active (qS = 1.02 ± 0.05 g g-1 h-1), and the fermentation products acetate, lactate, succinate, formate, alanine and ethanol were formed with volumetric productivities (QP) ranging between 1.7 and 4.3 g L-1 h-1. The cumulative QP of the secreted products was 17.7 ± 0.1 g L-1 h-1.The overall aim of this project is to establish V. natriegens as a novel production platform for Industrial Biotechnology and to emphasize the potential of this organism for future work. In order to achieve this goal, a transcriptional and metabolic map under relevant process conditions is to be created as a basis for further Metabolic Engineering studies applying transcriptome and metabolome analyzes. The already available molecular biology toolbox will be applied to construct V. natriegens strains for the aerobic and anaerobic production of L-valine and succinate for the first time. For the developed strains, fermentation processes are to be established and optimized which are superior in their performance data to existing literature-described processes.