Abstract:Growth kinetics and induction strategy of a genetically engineered yeast Pichia Pastoris which boring human insulin gene were studied in this paper. The results indicated thatthe relationship of specific growth rate(μ) and residual concentration of glycerol is accorded with Monod Equation in phase of cell growth in which μmax=0.204h-1, and Ks=24.3g/L. The maximum cell yield of glycerol Y*X/S=0.497 g/g, and growth maintaining coefficient m=0.007(g/g·h), latter evidenced that the strain has potential of high density cultivation. It was discovered that the heterologous protein concentration could be increased efficiently by batch-fed yeast extract, peptone and trace elements in the phase of induction. The results that heterologous protein concentration reached 256mg/L in 10L fermentor fermentation, which is 4 times more than flask fermentation level, may guide industrial production.
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