Association with Soil Bacteria Enhances p38-Dependent Infection Resistance in Caenorhabditis elegans

摘要: ABSTRACT The importance of our inner microbial communities for proper immune responses against invading pathogens is now well accepted, but the mechanisms underlying this protection are largely unknown. In study, we used Caenorhabditis elegans to investigate such mechanisms. Since very little known about microbes interacting with C. in its natural environment, began by taking first steps characterize microbiota. We established a natural-like environment which initially germfree, wild-type larvae were grown on enriched soil. Bacterial members adult microbiota isolated culture and identified using 16S rRNA gene sequencing. Using pure cultures bacterial isolates as food, two, Bacillus megaterium Pseudomonas mendocina, that enhanced resistance subsequent infection Gram-negative pathogen aeruginosa. Whereas B. was linked impaired egg laying, corresponding trade-off between fecundity resistance, mechanism conferred P. mendocina depended weak induction genes regulated p38 MAPK pathway. Disruption ortholog, pmk-1, abolished protection. aeruginosa not Gram-positive Enterococcus faecalis. Furthermore, from similarly induced aeruginosagacA mutant attenuated virulence different elegans-associated sp. isolate. Our results support pivotal role conserved pathway microbiota-initiated suggest similarity may play