二元胺是聚酰胺、聚氨酯和聚脲等高分子材料合成的核心单体，生产需求巨大。在碳中和大背景下，合成生物基二元胺是实现低碳生产和可持续发展的有效途径，借助合成生物学、代谢工程、蛋白质工程等策略能够设计和开发高效的二元胺生物合成关键酶和途径。本工作简述了1,4-丁二胺、1,5-戊二胺、1,6-己二胺的天然或人工合成路径，围绕微生物从头合成发酵和全细胞催化两种合成策略综述了二元胺的合成进展，丁二胺的生物合成主要包括鸟氨酸脱羧与赖氨酸脱羧路径，目前主要以发酵法生产丁二胺，但丁二胺的产率较低，不能达到工业生产的需求；戊二胺的生物合成路径为赖氨酸脱羧，主要采用发酵法和全细胞催化法，其中全细胞催化合成戊二胺更为高效，技术趋于成熟，已被广泛应用于规模化生产；己二胺目前主要是通过构建人工途径进行生物合成。另外，针对二元胺生物合成过程遇到的副产物多、菌株活性差、产率低、分离纯化困难等问题与挑战，提出了结合代谢工程和蛋白质工程优化关键酶催化、探索二元胺积累造成细胞损伤的影响机制、增强酶催化专一性和活性以提高生产强度、优化发酵体系、简化后续分离纯化步骤等提高生物合成二元胺的方法，同时指明了未来生物基二元胺工作的重要方向并展望了生物基二元胺的发展前景。

In the context of carbon neutrality, bio-diamine synthesis is an effective way to achieve the low-carbon production and sustainable development. Using synthetic biology, metabolic engineering, protein engineering strategies, we are able to design and construct efficient key enzymes and pathways for the biosynthesis of diamines. In this work, the progress of diamine synthesis is reviewed around two synthetic strategies: microbial de novo fermentation and whole-cell catalysis. The main diamines include 1,4-butanediamine, 1,5-pentanediamine, and 1,6-hexamethylenediamine. The biosynthesis of butanediamine mainly includes ornithine decarboxylation and lysine decarboxylation pathways, and butanediamine is mainly produced by fermentation. However, the current yield of butanediamine is low and cannot meet the requirments of industrial production. The biosynthesis of pentanediamine depends on the decarbosylation of L-lysine, mainly by de novo fermentation and whole-cell catalysis. The whole-cell catalysis for pentanediamine is more efficient, which has been widely used in large-scale production with the maturity of the technology. Hexamethylenediamine is currently synthesized by constructing artificial pathways. In addition, to address the challenges encountered in the biosynthesis of diamines, such as many by-products, poor strain activity, low yield, difficult separation, and purification, we proposed methods to improve the biosynthesis of diamines by combining metabolic engineering and protein engineering to optimize key enzyme catalysis, exploring the mechanism of cell damage caused by diamine accumulation, enhancing the specificity and activity of enzyme catalysis to improve production intensity, and optimizing the fermentation system to simplify the subsequent separation and purification steps. Finally, we foresee the future direction and development prospect of diamine biosynthesis.