Date of this Version
https:// doi.org/10.1016/j.jff.2019.103485 Received 14 May 2019; Received in revised form 26 July 2019; Accepted 27 July 2019 Available online 17 August 2019 1756-4646/ © 2019 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/BY-NC-ND/4.0/).
Complex, indigestible free oligosaccharides as well as conjugated glycans are found in milk that shape the gut microbiome of infants. The activity of an endo-β-N-acetylglucosaminidase from B. longum subsp. infantis (B. infantis) is known to release N-glycans from native milk glycoproteins under physiological conditions. We investigated whether this enzyme is active in vivo in breastfed infants fed B. infantis EVC001. Using mass spectrometry, we found 19 N-glycans related to human milk glycoproteins increased in abundance, similar to previous work using bovine milk glycoproteins, and these 19 N-glycans matched unique specificities of this enzyme. Twenty N-glycans were unique to infants fed B. infantis EVC001. Bifidobacteriaceae were correlated with these glycans, confirming the relationship between B. infantis and released N-glycans. This suggests that this enzyme is active in vivo and releases N-glycans from milk glycoproteins, and may play a role in B. infantis EVC001 colonization of the gut microbiome.