细菌中L-甲硫氨酸生物合成和调控机制

L-methionine Biosynthesis and Regulatory Mechanisms in Bacteria

L-甲硫氨酸是一种必需氨基酸,在食品、饲料、化妆品和药品中具有广泛的应用。目前,L-甲硫氨酸是唯一无法用微生物发酵法工业化生产的必需氨基酸,近年来,利用代谢工程提升L-甲硫氨酸产量受到国内外研究人员的普遍重视。本文主要分析了细菌中L-甲硫氨酸的生物合成途径及调控机制,着重分析了从高丝氨酸生物合成甲硫氨酸的三个关键步骤(即酰化、硫化和甲基化),并进一步对L-甲硫氨酸的生物合成提出展望,以期为L-甲硫氨酸的工业化生产提供指导。

L-methionine is an essential amino acid with a wide range of applications in food,feed,cosmetics and pharmaceuticals.Currently,L-methionine is the only essential amino acid that cannot be industrially produced by microbial fermentation.In recent years,the use of metabolic engineering to enhance the yield of L-methionine has received widespread attention from researchers at home and abroad.In this paper,the biosynthetic pathway and regulatory mechanism of L-methionine in Corynebacterium glutamicum and Escherichia coli are analysed;three key steps(i.e.,acylation,sulfurylation,and methylation)in the biosynthesis of methionine from hyper-serine are highlighted,and a further outlook on the biosynthesis of L-methionine is proposed with a view to providing guidance for the industrial production of L-methionine.