Ⅰ.Study On The Virulence Gene Spv On The Multidrug Resistant Salmonella Typhi Plasmid PR_ST98Ⅱ.Construction Of The Recombinant Adenovirus Vector Of HBx Protein Of HBV

Part I Study on the Virulence Gene spv on the Multidrug resistant Salmonella typhi Plasmid pRsT98Objective: This research is to identify and molecular analyze of plasmid(pRsT98) encoding multi-resistance to anti-microbial agents in S. typhipresenting the Salmonella plasmid virulence gene (spv).Methods: To identify whether the spv gene was presented on the Salmonellatyphi plasmid pRST98 or not, we got purified plasmid pRST98 and thenamplified the spv genes by PCR (Polymerase Chains Reaction), bysearching the already known sequence from Genebank and then designingprimers . Then the fragments spvR and spvB were got, and were ligated toplasmid vector pGEM-T. After the recombinant plasmids were amplified bybeing transformed into host cells DH5 ,the spvR and spvB fragmentspresented on recombinant plasmids were sequenced and bioinformaticlyanalyzed.Results: The open reading frame (ORF) of spvR sized 894bp,and spvB was1776bp. The homologous between spvR of pRsT98 and that of Salmonellatyphimurium was 99%; the sequence of spvB was completely the same tothat of Salmonella typhimurium . There was LysR domain in spvR. protein,while spvB had sal-spvB/VIP2 domain.Conclusion: DNA sequencing results presented in this study supported amosaic-like structure for pRST98, It suggests that except for the ability toencode multidrug resistance, the Salmonella typhi plasmid pRsi98 has spvgenes, and might also encode bacterial virulence. It can help usunderstanding the molecular mechanisms of pathogenesis of Salmonellatyphi.