Methanol oxidase from Hansenula polymorpha shows activity in peroxisome-deficient Pichia pastoris

Pichia pastoris can upgrade the methanol into various of high-valued biochemical products. This biosynthetic method was achieved mostly based on inherent methanol metabolism pathway of yeast. The alcohol oxidase (AOX) from Pichia pastoris plays a crucial role in methanol metabolism pathway. However, when the cells are exposed to excess methanol, the disruption of the peroxisome and inhibition of AOX enzyme activity happens. In our study，the strain Δ pex3 derived from P. pastoris GS115 was constructed as initial genetic engineering strain to simulate the damage of the peroxisome which was often happened under high concentrations of methanol. No AOX activity was detected in Δ pex3 with peroxisome defected. Subsequently, the methanol oxidase (MOX) from Hansenula polymorpha was employed to make up for activity loss of AOX. Introduction of MOX in the peroxisome-deficient strain Δ pex3 , thus new recombinant strain was obtained which named as Δ pex3 -MOX. Δ pex3 -MOX showed certain activity of alcohol oxidase, and the harvest biomass was higher compared to Δ pex3 . The ability of utilizing and toleration higher methanol was partially improved when methanol oxidase (MOX) from H. polymorpha was introduced compared to cells with peroxisome defected. • The activity of alcohol oxidase from P. pastoris could not be detected when cell peroxisome defected. • Methanol oxidase from H. polymorpha could be expressed and detected in P. pastoris with peroxisome defected. • Recombinant strain P. pastoris Δpex3-MOX could tolerate higher concentration of methanol.