Prokaryotic expression of HPV 16L1 and optimization of expression conditions / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To construct the HPV16 L1 prokaryotic expression plasmid and to optimize its expression.</p><p><b>METHODS</b>A pair of primers was designed according to plasmid sequences of pGEX-KG and the HPV16L1 genes published by GeneBank. The DNA fragment of 1500 bp was amplified by PCR from the HPV recombinant plasmid with HPV16L1 gene, then cloned into pGEX-KG and transformed into the host E.coli strain JM109. The pGEX-KG-HPV16L1 plasmid was taken and transformed into BL21(DE3) for expression. Induced by IPTG at 37 degree, the expression product of HPV16L1 gene was identified by SDS-PAGE and Western blot.</p><p><b>RESULTS</b>HPV16L1 fusion protein was expressed successfully in the form of inclusion bodies. The molecular weight was 83 kD. Meanwhile, the optimum condition of HPV16L1 fusion protein expression was induced with 1.0 mmol*L(-1) IPTG for 4 h. The fusion protein reacted specifically with antibodies against HPV16L1.</p><p><b>CONCLUSION</b>The prokaryotic expression vector of HPV16L1 gene has been constructed and expressed in E.coli successfully.</p>

Construction, Expression and Evaluation of the System Reporting Streptococcus pneumoniae Virulent Gene by GFP in vivo / 微生物学通报

Streptococcus pneumoniae(S.pn) is an opportunity pathogenic bacteria,environmental factors play a key role in the pathogenicity of S.pn. It is important to study virulent gene in vivo. The S.pn suicide plasmid containing gfp reporter was constructed by fusing the genes pneumolysin and gfp,in which gfp is an excellent molecule probe in vivo. The plasmid was integrated to No.22 S.pn by homologous recombination. The recombinant S.pn was gained and evaluated in aspects of fluorescence excitation, biological character and physio-activity. The results showed it is efficient and available to report the expression of virulent genes in vivo and in vitro, which will provide a new easy method for evaluating and screening the virulent genes of S.pn in vivo.