AHR and Enterobacteriaceae Infections: Notably, Bifidobacterium-derived acetate has previously been shown to mitigate the pathogenesis of Enterobacteriaceae infection in an animal model (60), and B. infantis-derived indole-3-lactic acid production reduced pathogen-induced inflammation in enterocytes in vitro (52, 61) through activation of the aryl hydrocarbon receptor (52, 62).