Preliminary studies on expression of human lysozyme gene in Pichia pastoris

In order to express human lysozyme(hLYZ) gene in Pichia pastoris,one pair of primers was designed according to the published sequences for hLYZ,and the hLYZ gene was amplified by PCR and cloned into the yeast secretory expression vector pPIC9K to construct the recombinant plasmid pPIC9K-LYZ.The recombinant plasmid was transformed to P.pastoris GS115 after digested by restriction enzyme Sac I,and positive clones were screened with G418 resistance for expression induced by 0.5% methanol.SDS-PAGE confirmed the correct molecular weight of recombinant expression protein.Antibacterial assay showed that hLYZ had obvious inhibitory activity against micrococcus.These results indicate that hLYZ gene has been expressed successfully in P.pastoris.