Construction Multiple Gene Copies of β-glucosidase in Picchia pastoris and High-level Expression Using FM21 Medium
To further improve the expression level of β-glucosidase that the gene (bgl1) was cloned from Aspergillus niger in Pichia pastoris and cut down the cost of production, the integrating more copy number of the bgl1 gene, and optimizing the conditions of the fermentation using FM21 medium were studied in this work. The results showed the higher resistant to Zeocin transformant was obtained with 2.7 times high level expression than that of the parent recombinant strain by electro-transformation of pPICZαA-bgl1 into the recombinant Pichia pastoris that had better expressed β-glucosidase. The optimal fermentation conditions of production for β-glucosidase in shake flask cultivition using FM21 medium was obtained: initial pH6.0, methanol concentration 1.0％ added into the culture every 24h, His 0.1％ and PTM1 0.4％. In addition, Tween80 was found to increase the yield of the recombinant protein with the suitable concentration 0.2％. The β-glucosidase activity was up to 114.1IU/ml on the optimal conditions after 216h induction. The results showed we have achieved high-level expression of β-glucosidase in Pichia pastoris.
β-glucosidase copy number of the bgl1 gene FM21 medium fermentation conditions Pichia pastoris
Lin-guo ZHAO Li-juan LI Fei LI Tan-che ZHOU Li-yan HE
College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
国际会议
南京
英文
152-157
2010-10-22（万方平台首次上网日期，不代表论文的发表时间）