Expression,purification and activity assay of recombinant mouse protein kinase CK2? subunit from escherichia coli / 中国药理学通报

ABSTRACT

AIM To study the expression, purification and activity assay of recombinant mouse protein kinase CK2? subunit from Escherichia coli. METHEDS The recombinant plasmid containing mouse protein kinase CK2? subunit cDNA constructed successfully was transformed into Escherichia coli BL21 (DE3) and specifically induced by IPTG. The recombinant mouse CK2? subunit was sequentially purified by DE 52, P11 phosphocellulose and Heparin Sepharose chromatography. The purified recombinant protein was analysed by SDS PAGE. RESULTS One protein with molecular mass of 42 ku was overexpressed by inducing ITPG. The recombinant protein was composed of approximately 30 6% of the total bacterial proteins. From 278 mg soluble proteins, the yield of the CK2? protein was 4 7 mg. SDS PAGE analysis of the purified recombinant protein showed only one band in agreement with native mouse CK2? subunit. The recombinant mouse CK2? and ? subunits were mixed at the same molar ratio. The produced CK2 holoenzyme displayed full activity. The characteristics and functions of reconstituted CK2 holoenzyme were consistent with those of the given native CK2. CONCLUSION The recombinant protein is mouse protein kinase CK2? subunit.