Cloning,expression and identification of Plasmodium vivax aldolase

Objective:To clonePlasmodium vivaxaldolase(PvALD) gene,express and identify the recombinant PvALD protein in vitro.Methods:PCR was performed to amplify PvALD gene from blood sample of P.vivax infected patient.pET32c-PvALD recombinant plasmid was constructed and transformed intoE.colihost BL21(DE3+),IPTG was used to induce the recombinant protein PvALD fused with His tag.Induction time,IPTG concentration and media types were optimized for expression of PvALD in E.coli.Then recombinant protein was purified by His-NTA affinity chromatography and identified by SDS-PAGE and Western blot.Results:The PvALD PCR product was about 1.1 kb,meeting the expectation of predicted fragment size.The recombinant pET32c-PvALD plasmid was verified by sequencing that the insertion was 100% homology with GenBank reference sequence.Optimized condition for recombinant PvALD was at 1 mmol/L IPTG concentration,6 h and in LB medium.SDS-PAGE result showed that recombinant PvALD was about 60 kD.Western blot result showed that recombinant PvALD could be recognized by serum from vivax-malaria patient,but not by serum from falciparum-malaria patient.Conclusions:The PvALD gene is successfully cloned,and recombinant PvALD protein is expressed,which offers basis for diagnosis rapidly.