Department of Biochemical Engineering, Institute for Synthetic Biosystem, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, P. R. China.
Biotechnol J. 2020 Sep;15(9):e1900494. doi: 10.1002/biot.201900494. Epub 2020 May 29.
Microbes play an important role in biotransformation and biosynthesis of biofuels, natural products, and polymers. Therefore, microbial manufacturing has been widely used in medicine, industry, and agriculture. However, common strategies including enzyme engineering, pathway optimization, and host engineering are generally inadequate to obtain an efficient microbial production system. Transporter engineering provides an alternative strategy to promote the transmembrane transfer of substrates, intermediates, and final products in microbial cells and thus enhances production by alleviating feedback inhibition and cytotoxicity caused by final products. According to the current studies in transport engineering, native transporters usually have low expression and poor transportation ability, resulting in inefficient transport processes and microbial production. In this review, current approaches for transporter mining, characterization, and verification are comprehensively summarized. Practical approaches to enhance the transport system in engineered cells, such as balancing transporter overexpression and cell growth, and evolution of native transporters are discussed. Furthermore, the applications of transporter engineering in microbial manufacturing, including enhancement of substrate utilization, concentration of metabolic flux to the target pathway, and acceleration of efflux and recovery of products, demonstrate its outstanding advantages and promising prospects.
微生物在生物燃料、天然产物和聚合物的生物转化和生物合成中发挥着重要作用。因此，微生物制造已广泛应用于医学、工业和农业。然而，常用的策略，包括酶工程、途径优化和宿主工程，通常不足以获得高效的微生物生产系统。转运蛋白工程提供了一种替代策略，可以促进微生物细胞中底物、中间产物和最终产物的跨膜转移，从而通过缓解最终产物引起的反馈抑制和细胞毒性来提高产量。根据转运蛋白工程的当前研究，天然转运蛋白的表达通常较低，运输能力较差，导致转运过程效率低下和微生物生产效率低下。在这篇综述中，全面总结了转运蛋白挖掘、表征和验证的当前方法。讨论了增强工程细胞中转运系统的实用方法，例如平衡转运蛋白的过表达和细胞生长，以及天然转运蛋白的进化。此外，转运蛋白工程在微生物制造中的应用，包括增强底物利用、将代谢通量集中到目标途径、加速产物外排和回收，展示了其突出的优势和广阔的前景。
