Expression and Quality Control of the Recombinant Human Serum Albumin and Interferon-Alpha2b Fusion Protein in Pichia pastoris

Abstract:

The engineering pichia pastorios GS115 is constructed which express recombinant human serum albumin and interferon-alpha2b fusion protein.The fermentation conditions are optimized in flask and 5 L fermentor.The surpernatant was purified by Blue Sepharose 6FF affinity chromatography,Phenyl Sepharose 6FF hydrophobic chromatography and Q Sepharose 6FF ion-exchange chromatography.The purified protein was detected by SDS-PAGE,molecular weight determination,nitrogen terminal sequence,endotoxin determination and anti-virus biological activity detection.The fermentation technology condition is stable and the harvest can reach 350 mg/L.The purity of purification protein is more than 95%.Molecular weight is 85 820.9 Da and amino acid sequence of nitrogen terminal is DAHKSEVAHRFKDLG.The result is correspond to the expected.The endotoxin is less than 5 EU/mg,which meet the standard requirement.The anti-virus activity of the protein is 1.6×106 IU/mg by bio-assay.It has excellent properties for industrial applications.