| Summary: | This study aimed to recover metagenome-assembled genomes (MAGs) from human fecal samples to characterize the glycosidase profiles of <i>Bifidobacterium</i> species exposed to different prebiotic oligosaccharides (galacto-oligosaccharides, fructo-oligosaccharides and human milk oligosaccharides, HMOs) as well as high-fiber diets. A total of 1806 MAGs were recovered from 487 infant and adult metagenomes. Unsupervised and supervised classification of glycosidases codified in MAGs using machine-learning algorithms allowed establishing characteristic hydrolytic profiles for <i>B. adolescentis</i>, <i>B. bifidum</i>, <i>B. breve</i>, <i>B. longum</i> and <i>B. pseudocatenulatum</i>, yielding classification rates above 90%. Glycosidase families GH5 44, GH32, and GH110 were characteristic of <i>B. bifidum</i>. The presence or absence of GH1, GH2, GH5 and GH20 was characteristic of <i>B. adolescentis</i>, <i>B. breve</i> and <i>B. pseudocatenulatum</i>, while families GH1 and GH30 were relevant in MAGs from <i>B. longum</i>. These characteristic profiles allowed discriminating bifidobacteria regardless of prebiotic exposure. Correlation analysis of glycosidase activities suggests strong associations between glycosidase families comprising HMOs-degrading enzymes, which are often found in MAGs from the same species. Mathematical models here proposed may contribute to a better understanding of the carbohydrate metabolism of some common bifidobacteria species and could be extrapolated to other microorganisms of interest in future studies.
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