CLONING AND EXPRESSION OF AspPecA PECTINASE GENE FROM Aspergillus niger M13 IN Pichia pastoris X33

Tóm tắt

This study aims to investigate the expression gene encoding pectinase (AspPecA) from Aspergillus niger M13 in Pichia pastoris X33 and the application of recombinant pectinase in fruit juice processing. A. niger M13 strain isolated from Da Xanh pomelo (Citrus maxima) peel was revived by culturing in Potato Dextrose Broth (PDB) at 35 ℃ for 18-20 h. The AspPecA gene was cloned into vector pPICZαA and expressed in P. pastoris X33 under the control of the AOX1 promoter. Purified rAspPecA had a molecular weight of approximately 42 kDa, as evidenced by SDS-PAGE. P. pastoris X33 transformants expressing recombinant pectinase were selected on an agar plate, and their ability to produce the pectinase was evaluated in flask cultures. Recombinant pectinase rAspPecA can clarify apple juice. Compared with controls, rAspPecA at a concentration of 2,400 U/L reduced apple juice turbidity by 29%. The results obtained in this work provide a basis for the development of applications of recombinant pectinase in various biotechnological fields.