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Prominent members of the human gut microbiota express endo-acting O-glycanases to initiate mucin breakdown.

ABSTRACT: The thick mucus layer of the gut provides a barrier to infiltration of the underlying epithelia by both the normal microbiota and enteric pathogens. Some members of the microbiota utilise mucin glycoproteins as a nutrient source, but a detailed understanding of the mechanisms used to breakdown these complex macromolecules is lacking. Here we describe the discovery and characterisation of endo-acting enzymes from prominent mucin-degrading bacteria that target the polyLacNAc structures within oligosaccharide side chains of both animal and human mucins. These O-glycanases are part of the large and diverse glycoside hydrolase 16 (GH16) family and are often lipoproteins, indicating that they are surface located and thus likely involved in the initial step in mucin breakdown. These data provide a significant advance in our knowledge of the mechanism of mucin breakdown by the normal microbiota. Furthermore, we also demonstrate the potential use of these enzymes as tools to explore changes in O-glycan structure in a number of intestinal disease states.

SUBMITTER: Crouch LI

PROVIDER: S-EPMC7419316 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Prominent members of the human gut microbiota express endo-acting O-glycanases to initiate mucin breakdown.

Crouch Lucy I LI Liberato Marcelo V MV Urbanowicz Paulina A PA Baslé Arnaud A Lamb Christopher A CA Stewart Christopher J CJ Cooke Katie K Doona Mary M Needham Stephanie S Brady Richard R RR Berrington Janet E JE Madunic Katarina K Wuhrer Manfred M Chater Peter P Pearson Jeffery P JP Glowacki Robert R Martens Eric C EC Zhang Fuming F Linhardt Robert J RJ Spencer Daniel I R DIR Bolam David N DN

Nature communications 20200811 1

The thick mucus layer of the gut provides a barrier to infiltration of the underlying epithelia by both the normal microbiota and enteric pathogens. Some members of the microbiota utilise mucin glycoproteins as a nutrient source, but a detailed understanding of the mechanisms used to breakdown these complex macromolecules is lacking. Here we describe the discovery and characterisation of endo-acting enzymes from prominent mucin-degrading bacteria that target the polyLacNAc structures within olig ...[more]

PMID: 32782292

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Dataset Information

Prominent members of the human gut microbiota express endo-acting O-glycanases to initiate mucin breakdown.

Publications

Prominent members of the human gut microbiota express endo-acting O-glycanases to initiate mucin breakdown.

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