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bioRxiv · 10.1101/2020.08.22.262196

Mutanofactin promotes bacterial adhesion and biofilm formation of cariogenic Streptococcus mutans

Li, Z.·Du, Y.·Sun, J.·Pan, A.·Zeng, L.·Maboudian, R.·Burne, R. A.·Qian, P.-Y.·Zhang, W.
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Abstract

Cariogenic Streptococcus mutans is known as a predominant etiological agent of dental caries due to its exceptional capacity in forming biofilms. From strains of S. mutans isolated from dental plaque, we here discover a polyketide/non-ribosomal peptide biosynthetic gene cluster, muf, which directly correlates with a strong biofilm-forming capability. We then identify the muf-associated bioactive product, mutanofactin-697 that contains a novel molecular scaffold, along with its biosynthetic logic. Further mode-of-action studies reveal mutanofactin-697 binds to S. mutans cells nonspecifically, increases bacterial hydrophobicity, and promotes bacterial adhesion and subsequent biofilm formation. Our findings provide the first example of a microbial secondary metabolite promoting biofilm formation via a physicochemical approach, highlighting the significance of secondary metabolism in mediating critical processes related to the development of dental caries.

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Li, Z., Du, Y., Sun, J., Pan, A., Zeng, L., Maboudian, R., Burne, R. A., Qian, P.-Y., Zhang, W.. 2020-08-23. Mutanofactin promotes bacterial adhesion and biofilm formation of cariogenic Streptococcus mutans. https://doi.org/10.1101/2020.08.22.262196

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