Fig. 6: Effects of microbiome bacterial competition on the biogeography of gut lumen colonization.

a Graphic representation of the pre-colonized and competition assay, with Ca. L. limosiae LUAb1 used from frozen bacterial preps and L. jeotgali LUAb3 from in vitro culture. Created with BioRender. b, c Representative RNA FISH-stained images of C. elegans N2 pre-colonized with LUAb3 and pulse exposed to LUAb1. Animals shown are fixed 24- and 48 hpe, respectively. Only the red fluorescence indicating LUAb1 is shown in all RNA FISH images. DAPI is shown in blue and scale bars are 100 µm. d, e Representative RNA FISH-stained images of N2 exposed to LUAb3 and LUAb1 simultaneously for 2 h. The animals shown are fixed at 24 hpe and 48 hpe. f Quantification and comparison of the percent of LUAb1 colonized past the midline in either pre-colonized or competed animals at two time points. Statistical analyses performed via Tukey’s multiple comparisons test in a one-way ANOVA where **p < 0.005 and ****p < 0.0001 for three independent experiments where n is at least 98 animals. g Total brood size of LUAb3 and competed animals in comparison to uncolonized animals across the span of 4 days. n = 60 for 3 independent experiments. h Lifespan during the most reproductively active period of uncolonized, LUAb3 pre-colonized, and competed animals where n = 60 for N = 3 independent experiments. Lifespan curves were analyzed by Mantel–Cox test, ****p < 0.0001.