Screening for High-yield Strain of Xylanase Produced by Engineered Pichia pastoris and Optimization of the Methanol Induced Conditions
[Objective] The aim of the study was to screen high-yield strain of xylanase by engineered Pichia pastoris and to optimize the methanol induced condition. [Method] Different concentrations of G418 on YPD plates were used to screen high-copy transformant, and then different concentrations of methanol were added into the medium at different time intervals to find the point of highest enzyme production. [ Result] A high-yield strain No. 16 was obtained which could bear 10.0 mg/ml of G418. When it was induced by 0.5% methanol at 30℃, the xylanase activity could reach the highest point of 826. 2 IU/ml. And its specific activity reached 5 229. 1 IU/mg. The enzyme production was high and stable when the methanol induced time interval was 12 h and the methanol concentration was 0. 8%. [ Conclusion] This strain was a methanol-dependent and high-yield one.
国家科技期刊平台
NSTL
万方数据
维普
