Growth inhibition of Akkermansia muciniphila by a secreted pathobiont sialidase

van Muijlwijk, G. H.; Bröring, E.; van Mierlo, G.; Jansen, P. W.; Vermeulen, M.; Aerts, P. C.; van Putten, J. P.; Palm, N. W.; de Zoete, M. R.

doi:10.1101/2022.03.15.484512

bioRxiv · 10.1101/2022.03.15.484512

Growth inhibition of Akkermansia muciniphila by a secreted pathobiont sialidase

van Muijlwijk, G. H.·Bröring, E.·van Mierlo, G.·Jansen, P. W.·Vermeulen, M.·Aerts, P. C.·van Putten, J. P.·Palm, N. W.·de Zoete, M. R.

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Abstract

Akkermansia muciniphila is considered a key constituent of a healthy gut microbiota. In inflammatory bowel disease (IBD), A. muciniphila has a reduced abundance while other, putative pathogenic, mucus colonizers bloom. We hypothesized that interbacterial competition may contribute to this observation. By screening the supernatants of a panel of enteric bacteria, we discovered that a previously uncharacterized Allobaculum species potently inhibits the growth of A. muciniphila. Mass spectrometry analysis identified a secreted Allobaculum sialidase as inhibitor of A. muciniphila growth. The sialidase targets sialic acids on casein O-glycans, thereby altering the accessibility of nutrients critical for A. muciniphila. The altered glycometabolic niche results in distorted A. muciniphila cell division and efficiently arrests its growth. The identification of a novel mechanism of A. muciniphila growth inhibition by a competing bacterial pathobiont may provide a rationale for interventions aimed at restoring and maintaining a healthy microbiota symbiosis in patients with intestinal disease.

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van Muijlwijk, G. H., Bröring, E., van Mierlo, G., Jansen, P. W., Vermeulen, M., Aerts, P. C., van Putten, J. P., Palm, N. W., de Zoete, M. R.. 2022-03-15. Growth inhibition of Akkermansia muciniphila by a secreted pathobiont sialidase. https://doi.org/10.1101/2022.03.15.484512

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