应用纤维素结合域标签构建谷氨酸棒状杆菌表达系统

Cost-effective production of protein by using cellulose-binding domain fusion tag in Corynebacterium glutamicum

摘要:

为优化谷氨酸棒状杆菌表达系统的纯化工艺，合成里氏木霉的CBD基因，将其与谷氨酸棒状杆菌分泌表达载体pXMJ19-sp连接，构建以CBD为纯化标签的重组载体pXMJ19-sp-CBD。在该载体中插入GFP基因并转化至谷氨酸棒状杆菌，可获得分泌表达融合蛋白GFP-CBD的重组菌。该菌经IPTG诱导后的发酵液在紫外灯下显示强烈的绿色荧光，重组蛋白的分泌表达量达200 mg/L。利用CBD标签对纤维素柱的可逆性吸附，可直接对谷氨酸棒状杆菌分泌到培养基中的重组蛋白进行纯化，从而简化工艺和降低成本，为工业化大生产奠定基础。

Abstract:

The CBD gene from Trichoderma reesei was cloned into the Corynebacterium glutamicum secretion expression vector pXMJ19-sp, in which green fluorescent protein was inserted to obtain pXMJ19-sp-GFP-CBD. After induced by 0.5 mmol/L IPTG, GFP-CBD was expressed in Corynebacterium glutamicum at high level of 200 mg/L. The GFP-CBD could be purified to high purity with cellulose column. The results indicated CBD can be successfully used in Corynebacterium glutamicum expression system and thus offer an extremely simple, effective and scalable way for production of recombinant proteins.