The effects of cultural conditions,which were fermentation period when methanol was as sole carbon source,methanol concentration,range of pH,on the expression of the chimeric protein of Plasmodium falciparum in genetically engineered methylotrophic Pichia pastoris were investigated by shake flask experiments in this paper.The results showed:(1)fermentation period with methanol inducement is about 96 hours;(2)the optimum methanol concentration as sole carbon source is 10g/L;(3)the range of pH is from 6.0 to 7.0. On the base of above experimental results the cell high-density fermentation had been done on the FMG-5L fermentor with multi-sensors.The results showed that the cell optical density (OD 600) can reached 550 and the ma-ximum expression level of target proteins was 780mg/L which was 4 times higher or more than the shake flask culture’s.
