RESUMEN
Objective To construct a prokaryotic expression vector pET-22b+with Middle East respiratory syndrome ( MERS) coronavirus nuclocapsid protein( NP) gene and to express and purify N protein.Methods N gene amplified by PCR was inserted into the prokaryotic expression vector pET-22b+.Recombinant plasmid was confirmed using DNA elec-trophoresis and sequencing.NP was expressed in E.coli BL21(DE3) by IPTG induced and purified by cation exchange chromatography using the AKTA purification system.Results The NP gene sequence was proved to be correct by sequen-cing and the protein was expressed in both soluble and insoluble forms in E.coli BL21 ( DE3 ) after IPTG induction.The purity and concentration of recombinant protein was improved obviously by cation exchange chromatography and enrich-ment.Conclusion Recombiant NP of high purity and concentration is purified and will facilitate NP functional research.