ABSTRACT
In this work,the Pichia pastoris expression system was applied to express the T.reesei EGⅣ.The eg4 gene was isolated from rice hull induced T.reesei culture through RT-PCR,and was ligated with the Pichia expression vector pPICZ?A,resulting in the recombinant plasmid pPICZ?A-eg4.The recombinant plasmid pPICZ?A-eg4 was then linearized and transformed into P.pastoris GS115,and the eg4 gene was in frame integrated into the Pichia genome through homologous recombination,resulting the recombinant strain P.pastoris-EGⅣ1.With methanol induction,the recombinant strain P.pastoris-EGⅣ1 expressed and secreated EGⅣ into the culture supernatant with CMC activity of 2.11U/mL.The SDS-PAGE analysis showed that the apparent molecular weight of expressed protein was about 50kD,slightly less than that produced by T.reesei.