Zhuang Yingping

High-expression of recombinant human concensus interferon-α by Pichia pastoris

The present work focused on the high expression of recombinant human consensus interferon-α (cIFN) by Pichia pastoris. The cycle of glycerol feeding, the strategy of methanol feeding and the optimum pH for protein induction were studied. The optimized strategies were a 4-h glycerol-feeding period, induction pH being kept at 5.0 and methanol concentration being kept under 5 g/L. The maximum dry cell weight, cIFN production and bioactivity obtained were 168, 1.24 g/L and 5.4 × 107 U/mL, respectively.

High cell density and high expression of recombinant human ApoA-lMilano in Escherichia coli by twice temperature-shifted induction

The effect of temperature on the formation of recombinant protein, apolipoprotein A-IMilano was investigated in the present study. The temperature of the initial growth phase was set at 30°C, while temperature variation in induction phase was arranged in three modes. High cell-density culture of Escherichia coli and high expression of recombinant human by twice temperature-shifted induction were carried out. Experimental results showed that ApoA-IMilano reached 4.8 g/L with the final cell density of OD600, 150. It was found that twice temperature-shifted induction could successfully avoid the effect of acetic acid on cell density and the expression of the product. The present study provides a basic procedure for the production of recombinant ApoA-IMilano.