A team of researchers from Yunnan Cancer Hospital, Sichuan University, and collaborating institutions has deciphered the structural and functional mechanisms of Amuc_1547, a critical sialidase enzyme produced by the gut bacterium Akkermansia muciniphila . This enzyme plays a central role in breaking down mucins—glycoproteins that shield the gut lining—by removing sialic acid residues, a process essential for bacterial energy acquisition and gut microbiota balance.
Using high-resolution X-ray crystallography (2.0 Å), the team resolved the enzyme’s structure, revealing a six-bladed β-propeller catalytic domain linked to a carbohydrate-binding module (CBM)-like β-sandwich domain (Figure 1). Key structural discoveries include:
“This enzyme’s ability to sense metal ions and carbohydrates allows A. muciniphila to thrive in diverse gut environments,” said Dr. Rui Bao, corresponding author. “Understanding its unique mechanism opens doors to therapies targeting mucin metabolism in diseases like obesity and inflammatory bowel disease.”
Comparative analysis four sialidases of A. muciniphila revealed divergent domain architectures and sequence variations, suggesting niche-specific roles in gut microenvironments. These insights position Amuc_1547 as a model for GH181 family enzymes, reshaping the understanding of sialidase evolution and function.
See the article:
Structural and functional insights into metal coordination and substrate recognition of Akkermansia muciniphila sialidase Amuc_1547
https://doi.org/10.1186/s43556-025-00265-8
Molecular Biomedicine
23-Apr-2025