Cloning of Laccase Gene from Coriolus Versicolor and Optimization of Culture Conditions for Lcc1 Expression in Pichia Pastoris
A laccase cDNA lcc1 (GenBank accession number HM137002), without native signal peptide, was cloned by RT-PCR from total RNA of Coriolus versicolor. Recombination expression vector pPICZαA-lcc1 was constructed and transformed into Pichia pastoris KM71H after lineared. Recombination laccase was expressed at a higher level. Single factors of fermentation conditions of Pichia pastoris KM71H for laccase production were optimized. The results showed optimal culture conditions were as follows: medium initial pH 7.5, Cu2+ concentration 0.5mmol/L, methanol additive amount 1.0% and shaker rotate speed 210r/min. Furthermore, induction at low temperature was more suitable for lcc1 secretion. And addition of appropriate amount peptone and tyrosine in culture medium could enhanced lcc1 yields and reduce its degradation.