Carbohydrate-active enzymes from Akkermansia muciniphila break down mucin O-glycans to completion

Nat Microbiol. 2025 Feb;10(2):585-598. doi: 10.1038/s41564-024-01911-7. Epub 2025 Jan 31.

Abstract

Akkermansia muciniphila is a human microbial symbiont residing in the mucosal layer of the large intestine. Its main carbon source is the highly heterogeneous mucin glycoprotein, and it uses an array of carbohydrate-active enzymes and sulfatases to access this complex energy source. Here we describe the biochemical characterization of 54 glycoside hydrolases, 11 sulfatases and 1 polysaccharide lyase from A. muciniphila to provide a holistic understanding of their carbohydrate-degrading activities. This was achieved using a variety of liquid chromatography techniques, mass spectrometry, enzyme kinetics and thin-layer chromatography. These results are supported with A. muciniphila growth and whole-cell assays. We find that these enzymes can act synergistically to degrade the O-glycans on the mucin polypeptide to completion, down to the core N-acetylgalactosaime. In addition, these enzymes can break down human breast milk oligosaccharide, ganglioside and globoside glycan structures, showing their capacity to target a variety of host glycans. These data provide a resource to understand the full degradative capability of the gut microbiome member A. muciniphila.

MeSH terms

  • Akkermansia / enzymology
  • Bacterial Proteins / metabolism
  • Gastrointestinal Microbiome
  • Glycoside Hydrolases* / metabolism
  • Humans
  • Milk, Human / chemistry
  • Mucins* / chemistry
  • Mucins* / metabolism
  • Polysaccharide-Lyases / metabolism
  • Polysaccharides* / metabolism
  • Sulfatases* / metabolism

Substances

  • Mucins
  • Polysaccharides
  • Glycoside Hydrolases
  • Sulfatases
  • Polysaccharide-Lyases
  • Bacterial Proteins

Supplementary concepts

  • Akkermansia muciniphila