Over the past few decades, Escherichia coli (E. coli) remains the most favorable host among the microbial cell factories for the production of soluble recombinant proteins. Recombinant protein production (RPP) via E. coli is optimized at the level of gene expression (expression level) and the process condition of fermentation (process level). Presently, the reported studies do not give a clear view on the selection of methods employed in the optimization of RPP. Here, we have reviewed various optimization methods and their preferences with respect to the factors at expression and process levels to achieve the optimal levels of soluble RPP. With a greater understanding of these optimization methods, we proposed a stepwise methodology linking the factors from both levels for optimizing the production of soluble recombinant protein in E. coli. The proposed methodology is further explained through five sets of examples demonstrating the optimization of RPP at both expression and process levels.Key Points• Stepwise methodology of optimizing recombinant protein production is proposed.• In silico tools can facilitate the optimization of gene- and protein-based factors.• Optimization of gene- and protein-based factors aids host-vector selection.• Statistical optimization is preferred for achieving optimal levels of process factors.

中文翻译：

---

利用计算和实验方法逐步优化大肠杆菌中重组蛋白的生产。

在过去的几十年中，大肠杆菌（E. coli）仍然是微生物细胞工厂中生产可溶性重组蛋白的最有利宿主。通过大肠杆菌的重组蛋白生产（RPP）在基因表达水平（表达水平）和发酵过程条件（过程水平）上得到优化。目前，已报道的研究并未对选择RPP的最佳方法给出清晰的认识。在这里，我们已经综述了各种优化方法及其在表达水平和加工水平方面的偏好，以实现可溶性RPP的最佳水平。在对这些优化方法有更深入的了解之后，我们提出了一种逐步方法，将两个层面的因素联系起来，以优化大肠杆菌中可溶性重组蛋白的产量。