Conserved symbiosis between Akkermansia muciniphila and its mammalian host

Akkermansia muciniphila is a member of the healthy human intestine, and colonises the mucus layer that lines the intestinal epithelial cells. Apart from humans, Akkermansia 16S rRNA gene sequences can be detected in intestinal samples of numerous vertebrates. Both in humans and animal models the abundance of A. muciniphila can be linked to metabolic health. We could detect A. muciniphila in animals that belong to 15 out of 17 mammalian orders, while other Verrucomicrobia were detected in intestinal samples as well. Ten new A. muciniphila strains were isolated from chimpanzee, siamang, mouse, pig, reindeer, horse, and elephant. The isolates all had mucin-degrading capacity and showed high physiologic and genomic similarity to type strain A. muciniphila MucT. Overall, the genomes of the new isolates showed high (93.9% to 99.7%) average nucleotide identity and conservation of at least 75 out of 78 predicted mucin degradation and utilisation genes, as compared to A. muciniphila MucT. This low genomic divergence might indicate that A. muciniphila favours mucosal colonization despite the differences between the hosts that produce the intestinal mucus. This conserved symbiosis between A. muciniphila and many different animals could indicate a similar beneficial role of this organism in regulating host metabolic health.