L-Cysteine and L-methionine, as the only two sulfur-containing amino acids among the canonical 20 amino acids, possess distinct characteristics and find wide-ranging industrial applications. The use of different organisms for fermentative production of L-cysteine and L-methionine is gaining increasing attention, with being extensively studied as the preferred strain. This preference is due to its ability to grow rapidly in cost-effective media, its robustness for industrial processes, the well-characterized metabolism, and the availability of molecular tools for genetic engineering. This review focuses on the genetic and molecular mechanisms involved in the production of these sulfur-containing amino acids in . Additionally, we systematically summarize the metabolic engineering strategies employed to enhance their production, including the identification of new targets, modulation of metabolic fluxes, modification of transport systems, dynamic regulation strategies, and optimization of fermentation conditions. The strategies and design principles discussed in this review hold the potential to facilitate the development of strain and process engineering for direct fermentation of sulfur-containing amino acids.

中文翻译：

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使用代谢工程大肠杆菌微生物生产含硫氨基酸

L-半胱氨酸和L-蛋氨酸作为20种经典氨基酸中仅有的两种含硫氨基酸，具有独特的特性，具有广泛的工业应用。使用不同的生物体发酵生产 L-半胱氨酸和 L-甲硫氨酸正受到越来越多的关注，并作为首选菌株进行了广泛的研究。这种偏好是由于其在具有成本效益的培养基中快速生长的能力、其对工业过程的鲁棒性、良好表征的代谢以及基因工程分子工具的可用性。本综述重点关注在中产生这些含硫氨基酸的遗传和分子机制。此外，我们系统地总结了用于提高其产量的代谢工程策略，包括新靶标的识别、代谢通量的调节、运输系统的修改、动态调节策略和发酵条件的优化。本综述中讨论的策略和设计原则有可能促进含硫氨基酸直接发酵的菌株和工艺工程的发展。