Strain-specific strategies of 2′-fucosyllactose, 3-fucosyllactose, and difucosyllactose assimilation by Bifidobacterium longum subsp. infantis Bi-26 and ATCC 15697

Human milk oligosaccharides (HMOs) function as prebiotics for beneficial bacteria in the developing gut, often dominated by Bifidobacterium spp. To understand the relationship between Bifidobacterium utilizing HMOs and how the metabolites that are produced could affect the host, we analyzed the metabolism of HMO 2’-fucosyllactose (2’-FL), 3-fucosyllactose (3FL and difucosyllactose (DFL) in Bifidobacterium longum ssp. infantis Bi-26 and ATCC15697. RNA-seq and metabolite analysis was performed on samples at early (A600=0.25), mid-log (0.5-0.7) and late-log phases (1.0-2.0) of growth. Bifidobacterium longum subsp. infantis strain Bi-26 and ATCC15697 was used in this study with 2'-FL, 3FL and DFL as the test carbon sources and lactose or no carbohytdrate added control, Samples were done in duplicate with samples taken at early phase (A600 ~0.2) mid log (0.5-1.1) and late log (1.1+). ATCC15697 only had mid-log samples taken.