利用生物技术生产甲硫氨酸的研究进展  

Progress and Prospects for Methionine Bioproduction

作　　者：王隆洋[1] 闵伟红[1] 

机构地区：[1]吉林农业大学食品科学与工程学院,小麦和玉米深加工国家工程实验室,吉林长春130118

出　　处：《食品科学》2016年第3期280-285,共6页Food Science

基　　金：吉林省自然科学基金项目(20130101139JC)

摘　　要：甲硫氨酸广泛应用于饲料、食品、医药等诸多领域,其市场需求量逐年增长。现行的化学合成甲硫氨酸产物为外消旋混合物,且对环境污染严重,与生物技术生产甲硫氨酸相比,不具备可持续性。生物技术生产甲硫氨酸可分为微生物发酵法和酶法。科研人员一直尝试阐明甲硫氨酸生物合成途径并进行高产菌株的选育,但由于其合成途径复杂,尚未获得适用于工业生产的菌株。对于现有菌株,深入研究甲硫氨酸生物合成途径、扩大甲硫氨酸向胞外的输出量、对发酵培养基组分及工艺条件进行优化都是有效提高甲硫氨酸产量的途径。酶法生产甲硫氨酸可分为异构体拆分和化合物酶解,其中利用微生物酶实现D型向L型的转化更有助于增加L-甲硫氨酸得率;最新的化合物酶解法结合了基因工程及酶的固定化技术,在实际生产中也具有巨大潜力。本文总结了国内外甲硫氨酸生产近况,重点论述了微生物发酵法、酶法及二者相结合生产甲硫氨酸的最新研究进展,并针对甲硫氨酸的发酵生产特点,提出变构抑制的解除、复合硫源的应用及关键酶的稳定性三方面的问题及建议。鼓励将酶法与发酵法相结合,并提倡通过酶解植物蛋白获得甲硫氨酸的研究,以实现低成本、低污染、高产量、高纯度的甲硫氨酸生产。Methionine is widely used in many fields such as feed, food, pharmaceutical and biotechnology, and has an increasing market demand. Compared with chemical synthesis, the biological production of methionine has many advantages especially in sustainable production and environmental protection. The biological methods used for methionine production include microbial fermentation and enzymatic treatment. Researchers have been trying to describe the biosynthetic pathway of methionine and breed high methionine-producing strains. However, no bacteria are now used in industrial production of met hionine because of the complex biosynthesis pathway of this amino acid and the affi nity with other intracellular reaction systems. In-depth study of methionine biosynthesis pathway, expansion of methionine exporting system and optimization of fermentation conditions are effective to increase the yield of methionine produced by the existing strains. The stateof-the-art technology of enzymatic hydrolysis for the production of methionine, combining genetic engineering with enzyme immobilization, has great application potential. This article summarizes the latest advances in the biotechnologies for methionine production in China and abroad with emphasis on microbial fermentation, enzymatic treatment and their combination. According to the characteristics of methionine production by microbial fermentation, existing problems and corresponding suggestions with respect to the removal of allosteric inhibition, the application of composite sulfur source and the stability of key enzymes are put forward. The combination of enzymatic treatment and microbial fermentation is recommended to be used for the production of methionine from preferably hydrolyzed plant proteins, achieving the advantages of low cost, low pollution, high yield and high purity.

关 键 词：甲硫氨酸 生物技术 微生物发酵 酶法生产 异构体拆分 化合物酶解 

分 类 号：Q517[生物学—生物化学]