Abstract: Recombinant conotoxins could be simply synthesized by genetic engineering, and fermentation conditions affect its expression yield. To obtain high expression, the fermentation conditions for engineered E. coli were optimized by using single factor test methods, such as fermentation time, IPTG concentration, initial pH and fermentation temperature. Expression of total protein in the supernatant was measured using a Protein Assay Kit, which was separated in Tricine-SDS-PAGE and the amount of recombinant conotoxins was analyzed by scanning grayscale analysis. The results showed that the optimum fermentation conditions were as follows: fermentation time was 4 h, IPTG concentration was 0.4 mmol/L, initial pH was 6.0, and the fermentation temperature was 26℃, the expression yield was 18 mg/L after optimization. The results laied a solid foundation for large-scale production of conotoxin MrVIB.

Key words: conotoxin, Escherichia coli, fermentation condition, optimization

摘要： 基因工程法能够简便易行的合成重组芋螺毒素，发酵条件会影响其表达产量。为获得高效表达，采用单因素试验法优化基因工程大肠杆菌的发酵条件如发酵时间、IPTG浓度、初始pH和发酵温度等。利用蛋白定量试剂盒测定表达上清总蛋白量，并用Tricine-SDS-PAGE电泳分离后灰度扫描分析重组芋螺毒素的含量。实验结果获得最佳发酵条件：发酵时间为4 h，IPTG浓度为0.4 mmol/L，培养基初始pH为6.0，发酵温度为26℃，优化后表达量为19.4 mg/L，研究结果为大规模生产芋螺毒素MrVIB奠定了坚实的基础。

关键词: 芋螺毒素, 大肠杆菌, 发酵条件, 优化