Utilization of a tetracycline-inducible system for high-level expression of recombinant proteins in Francisella tularensis LVSShow others and affiliations
2021 (English)In: Plasmid, ISSN 0147-619X, E-ISSN 1095-9890, Vol. 115, article id 102564Article in journal (Refereed) Published
Abstract [en]
Francisella tularensis is a Gram-negative intracellular pathogen causing tularemia. A number of its potential virulence factors have been identified, but their biology and functions are not precisely known. Understanding the biological and immunological functions of these proteins requires adequate genetic tools for homologous and heterologous expression of cloned genes, maintaining both original structure and post-translational modifications. Here, we report the construction of a new multipurpose shuttle plasmid – pEVbr – which can be used for high-level expression in F. tularensis. The pEVbr plasmid has been constructed by modifying the TetR-regulated expression vector pEDL17 (LoVullo, 2012) that includes (i) a strong F. tularensis bfr promoter, and (ii) two tet operator sequences cloned into the promoter. The cloned green fluorescent protein (GFP), used as a reporter, demonstrated almost undetectable basal expression level under uninduced conditions and a highly dynamic dose-dependent response to the inducer. The utility of the system was further confirmed by cloning the gapA and FTT_1676 genes into the pEVbr vector and quantifying proteins expression in F. tularensis LVS, as well as by studying post-translational modification of the cloned genes. This study demonstrates that high levels of recombinant native-like Francisella proteins can be produced in Francisella cells. Hence, this system may be beneficial for the analysis of protein function and the development of new treatments and vaccines.
Place, publisher, year, edition, pages
Elsevier, 2021. Vol. 115, article id 102564
Keywords [en]
ATc inducible, Expression plasmid, Francisella tularensis, Regulated bfr promoter
National Category
Biochemistry Molecular Biology Microbiology in the medical area
Identifiers
URN: urn:nbn:se:umu:diva-181586DOI: 10.1016/j.plasmid.2021.102564ISI: 000649111200005Scopus ID: 2-s2.0-85101554649OAI: oai:DiVA.org:umu-181586DiVA, id: diva2:1538575
2021-03-192021-03-192025-02-20Bibliographically approved