Abstract:Objective: To construct the expression vector of human α1-microglobulin (α1M) gene, express α1M protein in Escherichia coli (E.coli), purify recombinant α1M protein and to verify its bioactivity. Methods: The α1M gene sequence was amplified by PCR and α1M protein was expressed in E.coli B834. The recombinant protein was purified by nickel column chromatography, ion-exchange column chromatography and size exclusion chromatography and its bioactivity was verified by ABTS method. Results: The expression vector of the α1M was successfully constructed by PCR and α1M protein was expressed by E.coli B834 in a soluble supernatant way. The α1M protein with 95% purity was acquired successfully by purification. The result of the size exclusion chromatography indicated that α1M protein exhibited as both monomer and dimer in the solution. Additionally, the recombinant protein exerted anti-oxidant activity by ABTS method. Conclusion: α1M could be highly expressed in supernatant solution in E.coli B834 strain and it can be easily purified. The recombinant protein exhibits anti-oxidant activity, laying a solid basis for further structural and functional study of the human protein.
