Fecal microbiota from children with vitamin A deficiency impair colonic barrier function in germ-free mice: The possible role of alterative bile acid metabolites

•Bacteroides and Bifidobacterium are positively correlated with children's serum vitamin A levels.•Transplantation of vitamin A–deficient fecal microbiota impairs colonic barrier function of mice.•Bacteroides and Bifidobacterium are decreased in mice transplanted with vitamin A–deficient fecal microbiota.•Vitamin A–deficient microbiota alters bile acid metabolism pathways in the gut of transplanted mice.•The different metabolites are positively correlated with Bacteroides or Bifidobacterium.