Zhang W.-M.,Zhejiang Biotechnology Engineering Co. |
Hong J.,Zhejiang Biotechnology Engineering Co. |
Sun T.-W.,Zhejiang Biotechnology Engineering Co. |
Huang G.-T.,Zhejiang Biotechnology Engineering Co. |
And 3 more authors.
Chinese Journal of Biologicals | Year: 2012
Objective: To optimize the condition for expression of long chain Arg3 human insulin-like growth factor-1 (LR3IGF-1) in Pichia pastoris. Methods: The effects of methanol concentration (0.25%, 0.50%, 0.75%, 1.00%, 1.25% and 1.50%), temperature(25, 28 and 30°C), pH value(4.75, 5.00, 5.25, 5.50, 5.75 and 6.00) and additives (0.1% Arg, Gly, His, Tween-20 and Tween-80) on expression of LR3IGF-1 in P. pastoris were investigated, based on which the condition for expression of LR3IGF-1 was optimized. The expression of LR3IGF-1 in fermenter was induced under the optimized condition, and the expression level was determined and compared with that under original condition. Results: The expression levels of LR3IGF-1 after induction with 0.75% methanol and at 25°C were 76.5 and 98 mg/L respectively. The expression level of LR3IGF-1 was high after induction at pH 5.25 for 24 h, with low degradation. After addition of Tween-20, the expression level increased to 271 mg/L. The expression level of LR 3IGF-1 under optimized condition reached 497 mg/L, which increased by nearly 9 folds as compared with that before optimization of condition for expression, while the time for induction was shortened from 48 h to 24 h. Conclusion: The condition for expression of LR3IGF-1 in P. pastoris was optimized, which laid a foundation of large-scale production of LR 3IGF-1.