High-level expression and characterization of pectin methylesterase PmeT from Talaromyces leycettanus JCM12802 in Pichia pastoris

Abstract:

[Objective] We highly expressed the high temperature resistant pectin methylesterase from Talaromyces leycettanus JCM12802 in Pichia pastoris and studied its enzymatic properties. Pectin methylesterase with high catalytic efficiency at high temperature was expected to be widely used in the production of low-methoxyl pectin, for an optimal production process and conversion rate with reduced production cost.[Methods] We cloned the cDNA of pectin methylesterase gene (PmeT) from the total RNA of T. leycettanus JCM12802 as template by RT-PCR, which was inserted into the expression vector pPIC9K and transformed into P. pastoris GS115. We cultivated the high activated positive transformant for high-density fermentation.[Results] The recombinant pectin methylesterase (r-PmeT) expression level reached 428 U/mL. We have identified the enzymatic properties of r-PmeT. The optimum reaction temperature of r-PmeT was 75℃, and its thermostability was below 85℃. The optimum pH was 4.0, and it was stable between pH 2.0 and 7.0.[Conclusion] The recombinant Pichia pastoris could express high level pectin methylesterase from T. leycettanus JCM12802, which shows excellent application potential in its future industrial.