大肠杆菌合成生物基塑料单体5-氨基戊酸的代谢工程

Production of 5-aminovaleric acid,a bio-based plastic monomer by metabolic engineering of Escherichia coli

5-氨基戊酸可作为新型塑料尼龙5和尼龙5,6的前体。尼龙5和尼龙5,6是重要的工程塑料,应用于机械、化工、仪表、汽车等工业。目前几种5-氨基戊酸的生物合成法普遍产率较低且合成过程复杂,成本高,无法实现大规模工业生产。本研究中,笔者构建了一种基于单酶L-赖氨酸α-氧化酶RaiP表达的工程菌株,采用发酵和全细胞催化两种方式,实现了5-氨基戊酸的高效生产。在添加体积分数4%乙醇的条件下,工程菌株CJ02可生产5-氨基戊酸1.26 g/L。在加入体积分数4%的乙醇和10 mmol/L H2O2的反应器中,5-氨基戊酸的质量浓度可达到29.12 g/L。本研究对5氨基戊酸的生物合成工艺开发具有指导作用,有利于实现生物基塑料生产的工业化。

5-Aminopentanoic acid can be used as a precursor of the new plastic Nylon 5 and Nylon 5,6.Nylon 5 and nylon 5,6 are important engineering plastic,and can be used in machinery,chemical,instrumentation,automotive and other industries.At present,yield of several biosynthesis of 5-aminovaleric acid is generally low and production is complicated with high cost.Therefore,large-scale production can not be achieved.In this study,an engineered strain with single enzyme L-lysineα-oxidase(RaiP)expression was constructed,and the efficient production of 5-aminovaleric acid was achieved by fermentation and whole cell catalysis.The engineered strain CJ02 produced 1.26 g/L of 5-aminopentanoic acid under the conditions of adding 4%ethanol.In a reactor with the addition of 4%ethanol and 10 mmol/L H2O2,the final titer of 5-aminovaleric acid finally reached 29.12 g/L.The results have a guiding role in the process development of 5-aminovaleric acid biosynthesis,which is conducive to the industrialization of bio-based plastics production.