Methanol-Independent Protein Expression by AOX1 Promoter with trans-Acting Elements Engineering and Glucose-Glycerol-Shift Induction in Pichia pastoris.

ABSTRACT: The alcohol oxidase 1 promoter (P_AOX1) of Pichia pastoris is commonly used for high level expression of recombinant proteins. While the safety risk of methanol and tough process control for methanol induction usually cause problems especially in large-scale fermentation. By testing the functions of trans-acting elements of P_AOX1 and combinatorially engineering of them, we successfully constructed a methanol-free P_AOX1 start-up strain, in which, three transcription repressors were identified and deleted and, one transcription activator were overexpressed. The strain expressed 77% GFP levels in glycerol compared to the wide-type in methanol. Then, insulin precursor (IP) was expressed, taking which as a model, we developed a novel glucose-glycerol-shift induce

SUBMITTER: Wang J 

PROVIDER: S-EPMC5288789 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature