Effects of Amino Acids and Overexpression of dapA Gene on the Production of ε-Poly-L-lysine by Streptomyces diastatochromogenes Strains
Effects of Amino Acids and Overexpression of dapA Gene on the Production of ε-Poly-L-lysine by Streptomyces diastatochromogenes Strains
复制标题
氨基酸和dapA基因过表达对产色链霉菌菌株α-聚-L-赖氨酸生产的影响
DOI：
10.1007/s00284-021-02510-z
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发表时间：
2021-05-15
影响因子：
2.6
通讯作者：
Jia, Shiru
中科院分区：
文献类型：
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作者：
Li, Wenchao;Lv, Junge;Jia, Shiru
本研究以能高效合成epsilon-Poly-L-lysine的Streptomyces diastatochromogenes 6#-7菌株为研究对象，考察了18种氨基酸和dapA基因过表达对该菌株epsilon-PL发酵效率的影响。结果表明，l -脯氨酸、l -赖氨酸、l -异亮氨酸和l -苏氨酸均能促进epsilon-PL的产生。此外，二氢二吡啶酸合成酶基因（dapA）的过表达有助于提高异色葡萄球菌的发酵性能。在500 mL摇瓶中，过表达菌株（S. diastatochromogenes 12#-2）的最大epsilon-PL产量比原菌株提高了17.5%。在5-L发酵罐中发酵，发酵时间延长48 h， epsilon-PL产率达到30.54 g/L，比原菌株提高19.8%。本研究结果为增加链霉菌epsilon-PL的产量提供了一条有希望的途径，从而为降低产品epsilon-PL的成本和提高生产epsilon-PL的发酵效率铺平了道路。
In this study, the strain Streptomyces diastatochromogenes 6#-7, which efficiently synthesizes epsilon-Poly-L-lysine, was studied and the effects of 18 amino acids and overexpression of dapA gene on the fermentation efficiency of epsilon-PL by S. diastatochromogenes were investigated. It was shown that L-proline, L-lysine, L-isoleucine, and L-threonine could promote the production of epsilon-PL. Moreover, the overexpression of the dihydrodipicolinate synthase gene (dapA) helped improve the fermentation performance of S. diastatochromogenes. The maximum epsilon-PL yield of the overexpressing strain (S. diastatochromogenes 12#-2) increased by 17.5% compared with the original strain in 500 mL shake flask. When the fermentation was conducted in a 5-L fermenter, the fermentation duration was extended by 48 h, and epsilon-PL yield reached 30.54 g/L, which was a 19.8% increase compared to the original strain. The results of this study offered a promising approach to augment the production of epsilon-PL from Streptomyces, thus paving the way to reduce the cost of product epsilon-PL and enhance the fermentation efficiency of epsilon-PL production.