Expression of a single chain Fv antibody against clenbuterol in Pichia pastoris

A Pichia pastoris strain expressing recombinant anti-clenbutero (CBL) single chain Fv (scFv) was constructed.The recombinant plasmid,pPICZαA-CBL,was linearized by endonuclease BstX I and transformed into Pichia pastoris GS115 by electroporation.The multicopy transformants were obtained by Zeocin hyper-resistance screening and were induced to express by methanol.The induced culture supernatant was collected and detected by SDS-PAGE,western bloting and indirect competitive ELISA.The results showed that CBL scFv gene was inserted into the chromosome of GS115 successfully.The CBL scFv expressed from the pPICZαA-CBL recombinants showed 41kDa and anti-His-tag mAb recognized-activity by SDS-PAGE and Western blotting respectively,and could competitively combine with CBL,the IC50 was 5.1ng/mL.The yield of the CBL scFv was 0.095g/L.It suggested that a Pichia pastoris strain expressing CBL scFv had been constructed successfully.Further large scale production of CBL scFv could be continued on the basis of our study.