Chen Jingqi, Gai Yuanming, Fu Gang, Zhou Wenjuan, Zhang Dawei, Wen Jianping
Department of Biological Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, People's Republic of China.
Biotechnol Lett. 2015 Apr;37(4):899-906. doi: 10.1007/s10529-014-1755-3. Epub 2014 Dec 17.
α-Amylase was used as a heterologous model protein to investigate the effects of promoters, signal peptides and over-expression of an extra-cytoplasmic molecular chaperone, PrsA lipoprotein, on enhancing the secretion of α-amylase in Bacillus subtilis. Four promoters and six signal peptides were compared, successively, and the highest yield of α-amylase was achieved under the promotion mediated by PAprE, a strong constitutive promoter, and secretion by SPnprE, a signal peptide from B. subtilis. Moreover, under conditions of overexpressed PrsA lipoprotein, the secretion production and activity of α-amylase increased to 2.5-fold. The performance of the recombinant B. subtilis 1A751PL31 was evaluated with a fed-batch fermentation in a 7.5 l fermentor. Optimization of regulatory elements and over-expression of PrsA lipoprotein had a significant effect on enhancing the production of α-amylase in B. subtilis.
α-淀粉酶被用作异源模型蛋白，以研究启动子、信号肽以及胞外分子伴侣PrsA脂蛋白的过表达对增强枯草芽孢杆菌中α-淀粉酶分泌的影响。依次比较了四种启动子和六种信号肽，在强组成型启动子PAprE介导的促进作用下，以及来自枯草芽孢杆菌的信号肽SPnprE的分泌作用下，α-淀粉酶的产量达到最高。此外，在PrsA脂蛋白过表达的条件下，α-淀粉酶的分泌产量和活性提高到了2.5倍。在7.5升发酵罐中通过补料分批发酵对重组枯草芽孢杆菌1A751PL31的性能进行了评估。调控元件的优化和PrsA脂蛋白的过表达对提高枯草芽孢杆菌中α-淀粉酶的产量有显著影响。
