Construction of Recombinant Plasmid pQE32-HPV18L1 and Protein Expression

OBJECTIVE To develop recombina nt HPV18 vaccine by prokaryotic expression strategy. METHODS The L1 gene of HPV18 was amplifie d by PCR from pBR322-HPV18 and cloned into pUC19.The sequence of cloned HPV18 L 1 was confirmed by restriction analysis and DNA sequencing.A HPV18L1 prokaryoti c expression plasmid,pQE32-HPV18L1,was then constructed by subclone.pQE32HPV 18L1 transformed E.coli M15(with pREP4) was induced by IPTG. The expression of L1 protein was analyzed by SDS-PAGE and Western blot. RESULTS The amplified DNA fragment was in size of 1.7kb as expected.Restriction analysis showed that the amplified gene was inserted in pUC19 correctly.Sequence showed there was no mutation in both ends of the cloned L1.Restriction analysis showed that the recombinant pQE32-H PV18L1 was right.A Mr 63×10~3 protein could be seen in M15 in duced by IPTG with SDS-PAGE and was positive while reacting with HPV18 L1 antib ody by Western blot. CONCLUSIONS HPV18L1 is successfully clon ed and expressed in this study.