Performance of a highly successful outbreak strain of Mycobacterium tuberculosis in a multifaceted approach to bacterial fitness assessment

• Autores: Yokobori, Noemi; López, Beatriz; Monteserin, Johana; Paul, Roxana; von Groll, Andrea; Martin, Anandi; Marquina-Castillo, Brenda; Palomino, Juan Carlos; Hernández-Pando, Rogelio; Sasiain, María Del Carmen; Ritacco, Viviana
• Año de publicación: 2018
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: International Journal of Medical Microbiology 2018;308(3):349-347
• Materia: Aptitud Genética; Tuberculosis Resistente a Múltiples Medicamentos; Mycobacterium tuberculosis; Virulencia
• Institución: Administración Nacional de Laboratorios e Institutos de Salud "Dr. Carlos G. Malbrán"

Fil: Yokobori, Noemí. Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina. Academia Nacional de Medicina. Instituto de Medicina Experimental (IMEX), Buenos Aires; Argentina.
Fil: López, Beatriz. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.
Fil: Monteserin, Johana. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires; Argentina.
Fil: Paul, Roxana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.
Fil: Von Groll, Andrea. Universidade Federal do Rio Grande. Faculty of Medicine. Medical Microbiology Research Center, Porto Alegre, Río Grande del Sur; Brasil.
Fil: Martin, Anandi. Université Catholique de Louvain. Institute of Experimental and Clinical Research. Pôle of Medical Microbiology, Bruselas; Bélgica.
Fil: Marquina-Castillo, Brenda. Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán. Sección de Patología Experimental, Ciudad de México; México.
Fil: Palomino, Juan Carlos. Ghent University. Laboratory of Microbiology, Gante; Bélgica.
Fil: Hernández-Pando, Rogelio. Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán. Sección de Patología Experimental, Ciudad de México; México.
Fil: Sasiain, María Del Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina. Academia Nacional de Medicina. Instituto de Medicina Experimental (IMEX), Buenos Aires; Argentina.
Fil: Ritacco, Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires; Argentina.
Determining bacterial fitness represents a major challenge and no single parameter can accurately predict the ability of a certain pathogen to succeed. The M strain of Mycobacterium tuberculosis managed to spread and establish in the community and caused the largest multidrug-resistant tuberculosis outbreak in Latin America. We have previously shown that the M strain can manipulate the host immune response, but we still have no direct evidence, other than epidemiology, that can account for the enhanced fitness of the M strain. Our objective was to further characterize the performance of the outbreak strain M in different fitness assays. Two main aspects were evaluated: (1) molecular characterization of selected isolates from the M outbreak and related strains and (2) comparative fitness and in vivo performance of representative M strain isolates vs. the non-prosperous M strain variant 410. Our approach confirmed the multifaceted nature of fitness. Altogether, we conclude that the epidemiologically abortive strain 410 was vulnerable to drug-driven pressure, a weak competitor, and a stronger inductor of protective response in vivo. Conversely, the isolate 6548, representative of the M outbreak peak, had a growth disadvantage but performed very well in competition and induced lung damage at advanced stages in spite of reaching relatively low CFU counts. Integration of these observations supports the idea that the M strain managed to find a unique path to success.