Enhancing heterologous proteins production by MutSPichia pastoris via periodic methanol induction control

Abstract

AbstractThe methylotrophic Pichia pastoris is one of the most effective systems for producing many value‐added heterologous proteins. During protein expression by highly aerobic MutS P. pastoris induction system, traditional constant methanol control strategy leads to difficulty in enhancing the methanol oxidative reaction in methanol metabolism due to dissolved oxygen (DO) limitation and P. pastoris gradually loses the ability to synthesize proteins and metabolize methanol due to severe intracellular methanol accumulation. In this study, a novel periodic methanol control strategy was proposed to solve this loss of function problem. The strategy alternately shifted methanol induction environments in between “high methanol/low DO concentrations” and “high DO/low methanol concentrations” for 5–6 cycles and was applied for porcine interferon‐α (pIFN‐α) and human lysozyme (hLYZ) production. Compared with the traditional control, activities of both products increased over 100% and intracellular methanol content decreased to zero level which had positive environmental effect.