以乳糖为诱导剂的高密度发酵

High Density Fermentation Using Lactose as Inducer

以重组刺桐胰蛋白酶抑制剂 (r ETIa)为目的产物 ,用摇瓶比较了以异丙基 -β- D-半乳糖苷和乳糖诱导表达的差异 ,并在 15 L发酵罐中 ,以乳糖为诱导剂进行高密度发酵 ,摸索了诱导后碳、氮补加工艺对产物表达的影响 ,成功地使菌体密度达到 6 1(A6 0 0 ) ,表达量达到菌体总蛋白的 33% ,为乳糖替代

Recombinant Erythrina variegata trypsin inhibitor (rETIa) was used as a reporter protein in the development of a high-density fe rmentation process in which lactose was substituted for IPTG as inducer of T7 pr omoter. It was found that lactose was as efficient as IPTG in shaker flasks and fermentors. Through proper post-induction nutrient feeding strategy, a high cel l density of 61 ( A 600 ) and high expression level of protein rETIa (33% of the total cell protein) were achieved.