产HSA-CP融合蛋白毕赤酵母的发酵条件优化

Fermentation conditions of optimization of HSA-CP fusion protein expressed in Pichia pastoris

为提高重组毕赤酵母生产人血清白蛋白-C肽融合蛋白(HSA-CP)的产量和生产强度,在摇瓶条件下考察了甲醇诱导时间和浓度对目的蛋白产量的影响。结果表明,质量浓度10 g/L的甲醇诱导72 h最适于产物表达。通过对7L发酵罐中各因素的优化,得到最佳条件为:初始甘油质量浓度10 g/L,30℃培养,菌体生长期和诱导期的pH及溶氧分别控制在pH5.0、30%溶解O2或pH6.0、15%的溶解O2。10 g/L的甲醇诱导72 h,最终使干细胞质量浓度达到56.43 g/L,目的蛋白产量达368.45 mg/L。生产强度为3.920 mg/(L.h),目标蛋白的比生产速率为5.12 mg/(L.h)。

The key factors on high-level fusion protein HSA-CP production in recombinant Pichia pastoris were investigated in shake flask. It showed that with 10 g/L of methanol induced for 72 h, the yield of the target protein was high. By studying the yield of the target protein under different cultivation conditions in 7 L fermentor, the results were obtained as follows：firstly kept at pH 5.0 and 30% dissolved oxygen during the incubation period, then at pH 6. 0 and 15% dissolved oxygen during induction period, with initial glycerol concentration of 10 g/L at 30℃ for 72 h, dry cell mass. Finally, the maximum concentration of fusion protein reached 56.43 g/L and HSA-CP was 368.45 mg/L. The productivity reached 3.920 mg/（L·h）, the specific productivity of the target protein was 5. 12 mg/（L·h）.