• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.1022-1029
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• 2018

Tuberculosis (TB) remains a serious health issue around the word. Adenovirus (Ad)-based vaccine and modified vaccinia virus Ankara (MVA)-based vaccine have emerged as two of the most promising immunization candidates over the past few years. However, the performance of the homologous and heterologous prime-boost immunization regimens of these two viral vector-based vaccines remains unclear. In the present study, we constructed recombinant Ad and MVA expressing an Ag85B-TB10.4 fusion protein (AdH4 and MVAH4) and evaluated the impact of their different immunization regimens on the humoral and cellular immune responses. We found that the viral vector-based vaccines could generate significantly higher levels of antigen-specific antibodies, $IFN-{\gamma}$-producing splenocytes, $CD69^+CD8^+$ T cells, and $IFN-{\gamma}$ secretion when compared with bacillus Calmette-$Gu{\acute{e}}rin$ (BCG) in a mouse model. AdH4-containing immunization regimens (AdH4-AdH4, AdH4-MVAH4, and MVAH4-AdH4) induced significantly stronger antibody responses, much more $IFN-{\gamma}$-producing splenocytes and $CD69^+CD8^+$ T cells, and higher levels of $IFN-{\gamma}$ secretion when compared with the MVAH4-MVAH4 immunization regimen. The number of $IFN-{\gamma}$-producing splenocytes sensitive to $CD8^+$ T-cell restricted peptides of Ag85B (9-1p and 9-2p) and Th1-related cytokines ($IFN-{\gamma}$ and $TNF-{\alpha}$) in the AdH4-MVAH4 heterologous prime-boost regimen immunization group was significantly higher than that in the other viral vector-based vaccine- and BCG-immunized groups, respectively. These results indicate that an immunization regimen involving AdH4 may have a higher capacity to induce humoral and cellular immune responses against TB in mice than that by regimens containing BCG or MVAH4 alone, and the AdH4-MVAH4 prime-boost regimen may generate an ideal protective effect.

• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1339-1348
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• 2015

Until now, considerable effort has been made to engineer novel nitrogen-fixing organisms through the transfer of nif genes from various diazotrophs to non-nitrogen fixers; however, regulatory coupling of the heterologous nif genes with the regulatory system of the new host is still not well understood. In this work, a 49 kb nitrogen fixation island from P. stutzeri A1501 was transferred into E. coli using a novel and efficient transformation strategy, and a series of recombinant nitrogen-fixing E. coli strains were obtained. We found that the nitrogenase activity of the recombinant E. coli strain EN-01, similar to the parent strain P. stutzeri A1501, was dependent on external ammonia concentration, oxygen tension, and temperature. We further found that there existed a regulatory coupling between the E. coli general nitrogen regulatory system and the heterologous P. stutzeri nif island in the recombinant E. coli strain. We also provided evidence that the E. coli general nitrogen regulator GlnG protein was involved in the activation of the nif-specific regulator NifA via a direct interaction with the NifA promoter. To the best of our knowledge, this work plays a groundbreaking role in increasing understanding of the regulatory coupling of the heterologous nitrogen fixation system with the regulatory system of the recipient host. Furthermore, it will shed light on the structure and functional integrity of the nif island and will be useful for the construction of novel and more robust nitrogen-fixing organisms through biosynthetic engineering.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.580-580
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• 2003

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.617-617
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• 2003

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.228.1-228
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• 2005

• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.122-124
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• 2003

Cyclodextrin glucanotransferase (CGTase) and endoxylanase genes of Bacillus sp. were subcloned down-stream of yeast ADH1 promoter and expressed in S. cerevisiae. Most of the CGTase and endoxylanase expressed were detected in the extracellular medium with activity of 0.6 and 7-8 unit/ml, respectively. The recombinant enzymes were secreted as N-linked-glycosylated forms, resulting an enhanced thermal stability. CGTase predominantly produced $\alpha-cyclodextrin$ from starch and endoxylanase produced xylobiose and xylotriose from xylan.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.684-685
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• 2005

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.688-689
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• 2005

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.40-40
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• 2003

Recombinant plasmids harboring heterologous genes coding enhanced green fluorescent protein (EGFP) and erythropoietin (EPO) were transfected and expressed in Drosophila melanogaster S2 cells. Stably transformed cell populations expressing EGFP or monkey EPO were isolated after 4 weeks of selection with hygromycin B. (omitted)

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.12a
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• pp.69-69
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• 2004