Expression and purification of nine nucleocapsid proteins from coronaviruses / 基础医学与临床

ABSTRACT

Objective To define laboratory technology for expression and purification of nucleocapsid proteins of human coronaviruses SARS-CoV,HCoV-229E,HCoV-OC43,HCoV-NL63 and HCoV-HKU1,animal coronaviruses bovine coronavirus,murine hepatitis virus,feline infectious peritonitis virus,and infectious bronchitis virus.MethodsThe pET-30a-based recombinant plasmids containing full length nucleocapsid(N) protein of coronaviruses were transformed into E.coil BL21(DE3) competent cells and were induced to express N proteins by IPTG.The expression products were purified by ion exchange chromatography and Ni2+ affinity chromatography,and were verified by SDS-PAGE and Western blot.Results Nine coronavirus nucleocapsid proteins with correct Mr were solubly expressed and highly purified with purity over 90%.Conclusion Successfully expressed nine recombinant nucleocapsid proteins with high purity in E.Coli,which provides materials to study the function of these coronavirus N proteins.