Colonización artificial del intestino de ratón

Colonización artificial del intestino de ratón

Con el objetivo de estudiar el potencial de las bacterias para colonizar ambientes diferentes al propio, se tomaron inóculos de diversas fuentes (intestinos humanos, de pez cebra y termita; piel y lengua humana; tapetes microbianos y suelo), y se introdujeron mediante la dieta en intestinos de ratón libres de gérmenes.

El experimento, que se llevó a cabo en varias etapas, muestra que gracias a sus capacidades metabólicas (inferidas mediante pirosecuenciación y análisis cromatográficos), que consisten principalmente en la capacidad para metabolizar carbohidratos y ácidos biliares, las comunidades de bacterias de distintos ambientes (analizadas por medio de amplicones del gen 16S), tienen la capacidad para colonizar el intestino de ratón.

Aunque el efecto parece ser persistente, en la cuarta etapa del experimento los ratones con el xenomicrobioma fueron puestos en contacto con ratones de microbiota “normal”, lo que gracias a la coprofagia resulta en la pérdida de la xenomicrobiota.

Figure 5. Analysis of Ecological Invasion in Stages 3 and 4 Cohousing Experiments In stage 3 experiments, the GF mouse was cohoused with three mice transferred from stage 2: one with selected zebrafish gut xenomicrobiota, another with a selected termite hindgut xenomicrobiota, and a third with a selected soil community. During the stage 4 experiments, an ex-GF mouse from stage 3 that had acquired a composite xenomicrobiota was cohoused with a CONV-D mouse. (A) The proportions of the different xenomicrobiota sources represented in the microbiota of the GF bystander over time defined using Microbial SourceTracker. Mean values ± SD are presented. (B) Indicator species analysis identified bacterial 97%ID OTUs representative of the selected soil, termite hindgut, zebrafish hindgut, and mouse cecal microbiota at the end of stage 2. The heatmap shows the mean relative abundances of these OTUs in the fecal microbiota of each group of mice at each sampling time for Stages 2–4.

Figure 5. Analysis of Ecological Invasion in Stages 3 and 4 Cohousing Experiments In stage 3 experiments, the GF mouse was cohoused with three mice transferred from stage 2: one with selected zebrafish gut xenomicrobiota, another with a selected termite hindgut xenomicrobiota, and a third with a selected soil community. During the stage 4 experiments, an ex-GF mouse from stage 3 that had acquired a composite xenomicrobiota was cohoused with a CONV-D mouse. (A) The proportions of the different xenomicrobiota sources represented in the microbiota of the GF bystander over time defined using Microbial SourceTracker. Mean values ± SD are presented. (B) Indicator species analysis identified bacterial 97%ID OTUs representative of the selected soil, termite hindgut, zebrafish hindgut, and mouse cecal microbiota at the end of stage 2. The heatmap shows the mean relative abundances of these OTUs in the fecal microbiota of each group of mice at each sampling time for Stages 2–4.

Seedorf, H., Griffin, N. W., Ridaura, V. K., Reyes, A., Cheng, J., Rey, F. E., … & Spormann, A. M. (2014). Bacteria from diverse habitats colonize and compete in the mouse gut. Cell, 159(2), 253-266.