المؤلفون: Forrellad, Marina Andrea, Blanco, Federico Carlos, Marrero Diaz de Villegas, Rubén, Vázquez, Cristina Lourdes, Yaneff, Agustín, García, Elizabeth Andrea, Gutierrez, Maximiliano Gabriel, Durán, Rosario, Villarino, Andrea, Bigi, Fabiana

المصدر: Frontiers in Microbiology ; volume 11 ; ISSN 1664-302X

مصطلحات موضوعية: Microbiology (medical), Microbiology

الإتاحة: https://doi.org/10.3389/fmicb.2020.570794Test

المؤلفون: Forrellad, Marina Andrea, Bianco, María Verónica, Blanco, Federico Carlos, Nuñez, Javier, Klepp, Laura Inés, Vazquez, Cristina Lourdes, Santangelo, María de la Paz, Rocha, Rosana Valeria, Soria, Marcelo, Golby, Paul, Gutierrez, Maximiliano Gabriel, Bigi, Fabiana

المصدر: BMC Microbiology ; volume 13, issue 1 ; ISSN 1471-2180

مصطلحات موضوعية: Microbiology (medical), Microbiology

الوصف: Background Tuberculosis is one of the leading causes of mortality throughout the world. Mycobacterium tuberculosis , the agent of human tuberculosis, has developed strategies involving proteins and other compounds called virulence factors to subvert human host defences and damage and invade the human host. Among these virulence-related proteins are the Mce proteins, which are encoded in the mce1 , mce2 , mce3 and mce4 operons of M. tuberculosis . The expression of the mce2 operon is negatively regulated by the Mce2R transcriptional repressor. Here we evaluated the role of Mce2R during the infection of M. tuberculosis in mice and macrophages and defined the genes whose expression is in vitro regulated by this transcriptional repressor. Results We used a specialized transduction method for generating a mce2R mutant of M. tuberculosis H37Rv. Although we found equivalent replication of the MtΔmce2R mutant and the wild type strains in mouse lungs, overexpression of Mce2R in the complemented strain (MtΔmce2RComp) significantly impaired its replication. During in vitro infection of macrophages, we observed a significantly increased association of the late endosomal marker LAMP-2 to MtΔmce2RComp-containing phagosomes as compared to MtΔmce2R and the wild type strains. Whole transcriptional analysis showed that Mce2R regulates mainly the expression of the mce2 operon, in the in vitro conditions studied. Conclusions The findings of the current study indicate that Mce2R weakly represses the in vivo expression of the mce2 operon in the studied conditions and argue for a role of the proteins encoded in Mce2R regulon in the arrest of phagosome maturation induced by M. tuberculosis .

الإتاحة: https://doi.org/10.1186/1471-2180-13-200Test

المؤلفون: Villafañe, Luciana, Forrellad, Marina Andrea, López, María Gabriela, Garbaccio, Sergio, Garro, Carlos, Rocha, Rosana Valeria, Eirin, María Emilia, Singh, Mahavir, Taboga, Oscar A., Bigi, Fabiana

المصدر: Microbial Physiology ; volume 29, issue 1-6, page 83-90 ; ISSN 2673-1665 2673-1673

مصطلحات موضوعية: Cell Biology, Applied Microbiology and Biotechnology, Physiology, Biochemistry, Microbiology, Biotechnology

الوصف: Bovine tuberculosis (bTB) is a disease produced by Mycobacterium bovis that affects livestock, wild animals, and humans. The classical diagnostic method to detect bTB is measuring the response induced with the intradermal injection of purified protein derivative of M. bovis (PPDb). Another ancillary bTB test detects IFN-γ produced in whole blood upon stimulation with PPDb, protein/peptide cocktails, or individual antigens. Among the most used M. bovis antigens in IFN-γ assays are the secreted proteins ESAT-6 and CFP-10, which together with antigen Rv3615c improve the sensitivity of the test in comparison to PPDb. Protein reagents for immune stimulation are generally obtained from Escherichia coli , because this bacterium produces a high level of recombinant proteins. However, E. coli recombinant antigens are in general contaminated with lipopolysaccharides and other components that produce non-specific IFN-γ secretion in in vitro assays. In this work, we produced the relevant ESAT-6, CFP-10, and Rv3615c M. bovis antigens as fusions to the polyhedrin protein from the baculovirus AcMNPV. We obtained chimeric proteins effectively incorporated to the occlusion bodies and easily purified the recombinant polyhedra with no reactive contaminants. In an IFN-γ assay, these fusion proteins showed equivalent sensibility but better specificity than the same M. bovis proteins produced in E. coli .

الإتاحة: https://doi.org/10.1159/000506687Test
https://www.karger.com/Article/Pdf/506687Test

المؤلفون: Forrellad, Marina Andrea, McNeil, Michael, Santangelo, María de la Paz, Blanco, Federico Carlos, García, Elizabeth, Klepp, Laura Inés, Huff, Jason, Niederweis, Michael, Jackson, Mary, Bigi, Fabiana

المساهمون: National Institutes of Health (NIH) Grant, ANCyPT Grant, INTA Grant

المصدر: Tuberculosis ; volume 94, issue 2, page 170-177 ; ISSN 1472-9792

مصطلحات موضوعية: Infectious Diseases, Microbiology (medical), Immunology, Microbiology

الإتاحة: https://doi.org/10.1016/j.tube.2013.12.005Test
https://api.elsevier.com/content/article/PII:S1472979213002230?httpAccept=text/xmlTest
https://api.elsevier.com/content/article/PII:S1472979213002230?httpAccept=text/plainTest