Expression and purification of IFN-α gene from bovine

The bovine IFN-α gene was synthesized using optimized codons based on computer analysis and cloned into pWL expression vector for expression in E.coli. SDS-PAGE analysis showed that the expressed protein had a molecular weight of 17 ku and accounted for 33 % of the total cellular protein. The expression product existed mainly in the form of inclusion body and could be purified by gradient ion exchange chromatography following denaturation/renaturation using the CM Sepharose Fast Flow renaturation system. The renatured BoIFN-α protein showed strong antiviral activity of 4.0 ×105 u/mg on MDBK/VSV test system.