Institute of Biochemical Engineering, Vienna University of Technology, Gumpendorfer strasse 1A/166-4, Vienna 1060, Austria.
Appl Microbiol Biotechnol. 2014 Apr;98(7):2937-45. doi: 10.1007/s00253-013-5445-1. Epub 2013 Dec 14.
Controlling the recombinant protein production rate in Escherichia coli is of utmost importance to ensure product quality and quantity. Up to now, only the genetic construct, introduced into E. coli, and the specific growth rate of the culture were used to influence and stir the productivity. However, bioprocess technological means to control or even tune the productivity of E. coli are scarce. Here, we present a novel method for the process-technological control over the recombinant protein expression rate in E. coli. A mixed-feed fed-batch bioprocess based on the araBAD promoter expression system using both D-glucose and L-arabinose as assimilable C-sources was designed. Using the model product green fluorescent protein, we show that the specific product formation rate can be efficiently tuned even on the cellular level only via the uptake rate of L-arabinose. This novel approach introduces an additional degree of freedom for the design of recombinant bioprocesses with E. coli. We anticipate that the presented method will result in significant quality and robustness improvement as well as cost and process time reduction for recombinant bacterial bioprocesses in the future.
控制大肠杆菌中重组蛋白的生产速率对于确保产品的质量和数量至关重要。到目前为止，仅通过引入大肠杆菌的遗传构建体和培养物的特定生长速率来影响和调节生产力。然而，用于控制甚至调整大肠杆菌生产力的生物技术手段却很少。在这里，我们提出了一种新颖的方法，用于对大肠杆菌中重组蛋白表达率进行工艺技术控制。设计了一种基于 araBAD 启动子表达系统的混合进料分批补料生物过程，该系统同时使用 D-葡萄糖和 L-阿拉伯糖作为可同化的 C 源。使用模型产物绿色荧光蛋白，我们表明，仅通过 L-阿拉伯糖的摄取速率，就可以有效地调节特定的产物形成速率，甚至在细胞水平上也是如此。这种新方法为使用大肠杆菌设计重组生物技术过程引入了一个额外的自由度。我们预计，该方法将在未来显著提高重组细菌生物技术过程的质量和稳健性，并降低成本和缩短工艺时间。
