中国生物工程杂志

Objective To develop an effectually secrete expression in Pichia pastoris and purification system of recombinant human Arginase(Arg), and to test the activity of recombinant Arg. Methods Human arginase gene in the correct reading frame inserted into Pichia expression vector (pPIC9) after signal peptide, recombinant Pichia expression plasmid pPIC-Arg was transformed it into the host strain GS115. Results An recombinant expression plasmid pPIC-Arg was generated successfully, and was identified by DNA sequencing; The recombinant protein was expressed in GS115 with high level, the recombinant arginase gene was expressed highly and secrete effectually in Pichia pastoris, and the expressed product had the normal bioactivity. The target protein can be released into the media, the expression of protein in the supernatants accounted for more than 80%. AfterUltrafiltration and gel filtration, the purity of recombinant Arg reached 95%, and the specific activity is about 310 IU/mg. Conclusions A set of protocols for high efficient the Pichia expression and purification has been established, which is simple, efficient and applicable.