Acceso usuarios
Colombia
Introducción. La búsqueda de microorganismos productores de compuestos antimicro bianos representa una estrategia para enfrentar la crisis global de la resistencia a los anti bióticos. La identificación de bacterias del género Streptomyces con actividad antagónica contra bacterias multirresistentes es el paso inicial para recuperar metabolitos antibacte rianos efectivos para inhibir estos organismos.
Objetivos. Reconocer fuentes promisorias para aislar bacterias filamentosas capaces de inhibir aislamientos clínicos incluyendo En terobacteriaceae productoras de BLEES y KPC, y MRSA.
Métodos. Se aislaron actino bacterias de rizosferas y un sistema de compostaje. Se eligieron aislamientos clínicos de MRSA, Escherichia coli, and Klebsiella pneumoniae resistentes para realizar las pruebas de antagonismo. La actividad antibacteriana se registró mediante un método de estrías cru zadas. Los aislamientos de Streptomyces se caracterizaron según el Proyecto Internacional Streptomyces y se identificaron mediante técnicas moleculares.
Resultados. Se obtuvieron nueve aislados de actinobacterias con actividad contra bacterias resistentes, dos de la rizos fera de aguacate, cuatro de un cerco vivo y tres de un sistema de compostaje; dos mostra ron actividad contra todas las bacterias resistentes evaluadas. La identificación taxonómica molecular encontró S. jumonjinensis, S. bacillaris, S. prasinus, S. microflavus y S. cadmiisoli como especies putativas para los aislados nativos.
Conclusiones. Se aislaron Streptomyces antagónicas contra Enterobacterias productoras de BLEE y KPC, y MRSA, validando el potencial de las rizosferas y los sistemas de compostaje para obtener bacterias productoras de antibióticos. Los aislados nativos presentaron características de Streptomyces; aunque el Blast de NCBI no mostró una resolución suficiente, EzBioCloud detectó la identidad de los aislados hasta especie.
Introduction. The search for microorganisms producing antimicrobial compounds repre sents a strategy to address the global crisis of antibiotic resistance. Identification of bacteria of the genus Streptomyces with antagonistic activity against resistant bacteria is the initial step for the subsequent recovery of effective antibacterial metabolites for the inhibition of these resistant organisms.
Objectives. Recognize promising sources to isolate filamentous bacteria able to inhibit clinical isolates, including ESBL- and KPC- producing Entero bacteriaceae and MRSA.
Methods. Actinobacteria were isolated from rhizospheres and a compost system. MRSA, Escherichia coli, and Klebsiella pneumoniae clinical isolates were chosen to address antagonism tests. Antibacterial activity was recorded by a cross-streak method. Streptomyces isolates were characterized according to International Streptomyces Project and the native isolates with antimicrobial activity were identified by molecular te chniques.
Results. Nine isolates of actinobacteria with activity against resistant-antibiotic bacteria were obtained, two from the avocado rhizosphere, four from a living fence and three from a composting system. Two of the isolates showed activity against all the tested antibiotic-resistant bacteria. Molecular taxonomic identification found S. jumonjinensis, S. bacillaris, S. prasinus, S. microflavus, and S. cadmiisoli as putative species for native iso lates.
Conclusions. Streptomyces with antibacterial activities against ESBL and KPC-pro ducing Enterobacteria and MRSA have been isolated and the potential of rhizospheres and compost systems for obtaining antibiotic-producing bacteria was validated. Native isolates exhibited common traits for Streptomyces; although NCBI’s Blast did not show a resolution to identification, EzBioCloud 16S-based identification was able to accurately detect the identity of the isolates down to the species level.
