毕氏酵母KM71和GS115发酵工艺的比较

Comparsion of Pichia Pastoris KM71 and GS115 in the Process of Expressing Recombinant Proteins

目的 探讨毕氏酵母菌KM71和GS1 1 5表达人可溶性FLt3配体、CD40L、IL - 1 3、IL -1 1及TNFα等外源蛋白的发酵工艺。方法 挑取KM71或GS1 1 5单个菌落在BMGY培养基中初步培养 ,在其A60 0 值达 2～ 6时 ,转入发酵罐中行高密度发酵。结果 KM71诱导表达时 ,对甲醇的需求较低 ,故添加甲醇速度应较慢 ,并应提高菌的接种浓度 ;而GS1 1 5菌株生长速度较快 ,代谢甲醇的能力较强 ,表达量相对较高。结论 KM71和GS1 1 5可用于不同性质外源蛋白的表达 ,表达量较高 ,是一种理想的表达系统。

Objective To investigate the difference between KM71 and GS115 as an expression system for recombinant proteins.Methods A single clone of KM71 or GS115 was added to BMGY, a medium of pichia pastoris . After the A 600 reached 2～6, the BMGY was transfered into a fermentator. A high density incubation was used for fermentation.Results The methanol concentration in the culture was the key to a successful induction of the synthesis of the desired protein, and was maintained at 1% throughout the phase. Less methanol was used during the induction of KM71. Thus, the rate of methanol addition must be slow. In order to get a high level of recombinant protein, the concentration of KM71 to the fermentation must be enhanced. Conversely, GS115 could use the methanol at a relatively high rate, the level of methanol added to GS115 might be a little high.Conclusion KM71 and GS115 may be a reasonable expression system to be used for expressing recombinant protein.