ABSTRACT
Objective:To construct pGEX-3X/hTSHa Escherichia coli(E.coli)expression system and prepare purified recombinant GST-recombinant human thyroid stimulating hormone(rhTSH)α protein.Methods:The complete coding sequence of hTSHα was obtained by RT-PCR with total RNA extracted from fresh chorial tissue as the template,and thereafter cloned into expression vector pGEX-3X by EcoRl and BamHI digestion.The recombinant plasmid was transformed into E.coli Mach1-T1 and then induced expression by WrG.The GST-rhTSHα fusion protein was identified by SDS-PAGE and its antigenicity was verified by a modified competitive ELISA.Results:A specific protein band of 36 ku,in accordance with predicted molecular weight,could be visualized in SDS-PAGE.As the result of ELISA,the recombinant GST-hTSHα protein can inhibit the intact TSH molecular binding with anti-TSHα antibody in a dose dependent manner.Conclusion:The cDNA of hTSHα was cloned and the recombinant expression vector pGEX-3X/hTSHα was constructed successfully.The recombinant GST-rhTSHα protein could be highly expressed in E.coli Machl-T1 and was approved of possessing antigenicity.
ABSTRACT
Objective:To construct suitable vectors for the secretory expression of hirudin in Pichia pastoris.Methods:The α-facor-hirudin gene was amplified from pPIC9-hirudin by PCR and sub-cloned into PA0815.The multi-copy recombinant plasmid pA0815-(α-Hirudin)n was constructed.The recombinant was transformed into P.pastoris strain GS115 for induction expression and then the activity of secreted products was identified.Results:A new multi-copy vector pA0815-(αHirudin)n was successfully constructed and was capable of secreting recombinant hirudin efficiently,which was confirmed respectively by PCR and SDS-PAGE.The products possessed the activity of thrombin inhibitor.Conclusion:This result offers efficient P.pastoris stains for mass production of biological active hirudin.
