Ayadi-Zouari Dorra, Kammoun Radhouane, Jemli Sonia, Chouayekh Hichem, Bejar Samir
Laboratory of Microorganisms and Biomolecules, Centre of Biotechnology of Sfax, Université de Sfax, BP 1177 Sfax, Tunisia.
Indian J Exp Biol. 2012 Jan;50(1):72-9.
The cyclodextrin glycosyltransferase (CGTase) of Paenibacillus pabuli US132 was fused to the secretive lipase signal peptide of B. subtilis. This leads to an efficient secretion of the recombinant enzyme into the culture medium of E. coli as an active and soluble form contrasting with the native construction leading to a periplasmic production. In order to enhance the yield of CGTase production, an experimental design methodology was applied for the optimization of the culture composition. Hence, the media components were submitted to preliminary screening using a Plakett-Burman design. The concentrations of the major operating ones were then optimized to enhance the secretion of CGTase using response surface methodology. The findings revealed that concentrations of 0.5% potato starch, 3% yeast extract, 3% tryptone, 1.5% casein hydrolysate, 0.5% NaCl, 0.2% KH2PO4, and 0.02% MgSO4 were the optimal conditions for CGTase production. The experimental value (9.43 U/mL) obtained for CGTase activity was very close to the predicted value (9.27 U/mL).
将巴氏芽孢杆菌US132的环糊精糖基转移酶（CGTase）与枯草芽孢杆菌的分泌性脂肪酶信号肽融合。这导致重组酶以活性和可溶形式有效分泌到大肠杆菌的培养基中，这与导致周质产生的天然构建体形成对比。为了提高CGTase的产量，应用了一种实验设计方法来优化培养成分。因此，使用Plakett-Burman设计对培养基成分进行了初步筛选。然后使用响应面方法优化主要操作成分的浓度，以提高CGTase的分泌。研究结果表明，0.5%马铃薯淀粉、3%酵母提取物、3%胰蛋白胨、1.5%酪蛋白水解物、0.5%氯化钠、0.2%磷酸二氢钾和0.02%硫酸镁的浓度是CGTase生产的最佳条件。CGTase活性的实验值（9.43 U/mL）非常接近预测值（9.27 U/mL）。
