›› 2008, Vol. 8 ›› Issue (1): 120-124.
• 生化工程专栏 • Previous Articles Next Articles
QIN Guo-hong,xiong-xiao-chao,ZHANG Ju-hua,XING Jian-min,LIU Hui-zhou
Online:
Published:
秦国宏,熊小超,张菊花,邢建民,刘会洲
Abstract: The synthesis of g-poly glutamic acid (g-PGA) by the strain Bacillus subtilis Natto NLSSe which can be used to synthesize nattokinase was investigated. g-PGA was synthesized in the medium without the addition of L-glutamic acid, showing that the strain was a L-glutamic acid-independent bacterium. The molecular weight of the g-PGA was about 2~3 million Dalton. The suitable carbon and nitrogen sources for the synthesis of nattokinase were sucrose and soya peptone respectively. The suitable carbon and nitrogen sources for the synthesis of g-PGA were citric acid and NH4Cl respectively. The results of orthogonal experiments showed that increasing the concentrations of soya peptone and citric acid could enhance the synthesis of nattokinase and g-PGA respectively, in the meantime the synthesis did not result in restraint formation between the two products. This merit was beneficial to the co-production. The yields of both products could achieve the levels of the single synthesis when the concentrations of soya peptone, NH4Cl and citric acid were 10, 9, 15 g/L respectively, the activity of nattokinase reached 121.2 U/mL, and the concentration of g-PGA reached 1.1 g/L.
Key words: g-PGA, nattokinase, L-glutamic acid-independent, Bacillus subtilis
摘要: 利用实验室保存的纳豆激酶生产菌Bacillus subtilis Natto NLSSe进行了g-聚谷氨酸合成研究,在不添加谷氨酸的培养基中合成了分子量在200~300 万Da的g-聚谷氨酸,表明该菌是谷氨酸非依赖型菌. 合成纳豆激酶的合适碳、氮源分别是蔗糖和大豆蛋白胨,合成g-聚谷氨酸的合适碳、氮源分别是柠檬酸和NH4C1. 通过正交实验研究了碳、氮源对纳豆激酶和g-聚谷氨酸联产的影响,结果表明,增加培养基中大豆蛋白胨及柠檬酸的浓度能分别促进纳豆激酶和g-聚谷氨酸的合成,而不抑制另一产物的合成,有利于纳豆激酶和g-聚谷氨酸的联产. 在大豆蛋白胨10 g/L, NH4C1 9 g/L,柠檬酸15 g/L时,纳豆激酶酶活为121.2 U/mL,g-聚谷氨酸产量为1.1 g/L,均达到了单独合成时的水平.
关键词: g-聚谷氨酸, 纳豆激酶, 非依赖型谷氨酸, 芽孢杆菌
QIN Guo-hong;xiong-xiao-chao;ZHANG Ju-hua;XING Jian-min;LIU Hui-zhou. Co-production of Nattokinase and g-Poly Glutamic Acid by Bacillus subtilis Natto NLSSe[J]. , 2008, 8(1): 120-124.
秦国宏;熊小超;张菊花;邢建民;刘会洲. 枯草芽孢杆菌联产纳豆激酶和g-聚谷氨酸[J]. , 2008, 8(1): 120-124.
0 / / Recommend
Add to citation manager EndNote|Ris|BibTeX
URL: https://www.jproeng.com/EN/
https://www.jproeng.com/EN/Y2008/V8/I1/120