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Animals selectively acquire specific symbiotic gut bacteria from their environments that aid host fitness. To colonize, a symbiont must locate its niche and sustain growth within the gut. Adhesins are bacterial cell surface proteins that facilitate attachment to host tissues and are often virulence factors for opportunistic pathogens. However, the attachments are often transient and nonspecific, and additional mechanisms are required to sustain infection. In this work, we use live imaging of individual symbiotic bacterial cells colonizing the gut of livingDrosophila melanogasterto show thatLactiplantibacillus plantarumspecifically recognizes the fruit fly foregut as a distinct physical niche.L. plantarumestablishes stably within its niche through host-specific adhesins encoded by genes carried on a colonization island. The adhesin binding domains are conserved throughout the Lactobacillales, and the island also encodes a secretion system widely conserved among commensal and pathogenic bacteria.
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A symbiotic physical niche in Drosophila melanogaster regulates stable association of a multi-species gut microbiota
Abstract The gut is continuously invaded by diverse bacteria from the diet and the environment, yet microbiome composition is relatively stable over time for host species ranging from mammals to insects, suggesting host-specific factors may selectively maintain key species of bacteria. To investigate host specificity, we used gnotobiotic Drosophila , microbial pulse-chase protocols, and microscopy to investigate the stability of different strains of bacteria in the fly gut. We show that a host-constructed physical niche in the foregut selectively binds bacteria with strain-level specificity, stabilizing their colonization. Primary colonizers saturate the niche and exclude secondary colonizers of the same strain, but initial colonization by Lactobacillus species physically remodels the niche through production of a glycan-rich secretion to favor secondary colonization by unrelated commensals in the Acetobacter genus. Our results provide a mechanistic framework for understanding the establishment and stability of a multi-species intestinal microbiome.
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- PAR ID:
- 10422763
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41467-023-36942-x
