Fig. 6

Monoassociations Reveal Distinct Bacterial Mechanisms for Inducing Fatty Acid Absorption in the Intestinal Epithelium (A–D) Representative confocal images of the intestinal epithelium of 6 dpf C-fed zebrafish raised GF (A) or monoassociated with Exiguobacterium sp. ZWU0009 (B), Chryseobacterium sp. ZOR0023 (C), or Pseudomonas sp. ZWU0006 (D) incubated with BODIPY-FL C₅ for 6 hr. BODIPY-C₅ accumulation in large epithelial lipid droplets (black arrowheads) and in the lamina propria (white arrow) is indicated. (E) Lipid droplet quantification in the intestinal epithelium of monoassociated zebrafish compared to GF controls. (F) Relative frequency of intestinal LD sizes in monoassociated zebrafish. The data represent the mean ± SEM of at least two independent experiments (5–16 fish/condition/experiment). Significant differences compared to GF controls are identified: *p < 0.05; ***p < 0.001. (G) BODIPY-C₅ fluorescence scores in the livers of monoassociated zebrafish compared to GF controls. The graph represents the mean ± SEM of at least two independent experiments (2–7 fish/condition/experiment) that were scored blindly (score scale 0–5). Significant differences to GF controls are identified: *p < 0.05. (H and I) Intestinal LD number (H) and relative frequency of intestinal LD sizes (I) in GF zebrafish treated with filter-sterilized Exiguobacterium sp., Chryseobacterium sp., or Pseudomonas sp. conditioned media. Results are presented as mean ± SEM of at least two independent experiments (3–7 fish/condition/experiment) with identified significant differences compared to GF control: **p < 0.01.