(A–D) E. coli-GFP (green) was cultured in the presence of 2 μM Cy3-labeled (red) hsa-miR-1226-5p, scrambled hsa-miR-1226-5p control, or hsa-miR-515-5p for 4 hr and washed with PBS, and fixed in 2% PFA, followed by nucleic acid staining with DAPI (blue). Images were acquired by confocal microscopy with a 100× objective. Merged channel and orthogonal view were processed with Fiji/ImageJ. Scale bars, 10 μm. Representative of 2 experiments (see also Movie S1 ).

(E) Fn was cultured in the presence of 1.25 μM Cy3-labeled (red) hsa-miR-515-5p, scrambled hsa-miR-515-5p control, or hsa-miR-1226-5p for 0, 5 min, 6 hr, and 12 hr and terminated on ice, washed once with cold PBS, and fixed with 2% PFA, followed by flow cytometry detection of Cy3 in the bacteria. The percentage of Cy3-miR positive Fn is shown. Representative of 2 experiments.

(F) E. coli-GFP was cultured in the presence of 2 μM Cy3-labeled (red) hsa-miR-1226-5p, scrambled hsa-miR-1226-5p control, or hsa-miR-515-5p for 0, 5 min, 2 hr, and 4 hr and terminated on ice, washed once with cold PBS, and fixed with 2% PFA, followed by flow cytometry detection of Cy3 in the GFP+ E. coli. The percentage of Cy3-miR positive E. coli is shown. Representative of 2 experiments.

(G) Fn was cultured in the presence of vehicle, 1.25 μM scrambled hsa-miR-515-5p control, hsa-miR-515-5p, mutated hsa-miR-515-5p, or hsa-miR-1226-5p for 16 hr. RNA was isolated, and the ratio of Fn 16S rRNA/23S rRNA transcript level was quantified by qPCR.

(H) E. coli was cultured in the presence of vehicle, 1.25 μM scrambled hsa-miR-1226-5p control, hsa-miR-1226-5p, mutated hsa-miR-1226-5p, or hsa-miR-515-5p for 4 hr. RNA was isolated, and transcript levels of E. coli yegH were quantified by qPCR.

(G and H) Values are mean ± SEM, one-way ANOVA followed by Dunnett’s multiple comparison tests. ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001, ∗∗∗∗p < 0.0001. Data summarize 3 independent experiments.