Bacteria as the most important human pathogens, play important roles in human health and disease. Small chemicals synthesized by bacterial biosynthetic gene clusters (BGCs) have a crucial role in microbiome-host and microbe-microbe interactions. BGCs are widely investigated in the human gut niche as potential mediators of interactions between microbes and hosts, while only a few studies have explored oral BGCs. Here, we used shotgun sequencing to profile the microbiota from three different oral sites, namely, saliva, subgingival, and supragingival niches. We used a systematic approach to analyze these samples to identify oral BGCs could be associated with periodontitis. In this pilot study we found 10,742 BGCs, some of which were unique for a specific oral site. We found novel BGCs are widely distributed among different phyla of bacteria and can potentially play key roles in periodontitis. Our findings expand the knowledge of oral microbiota by uncovering previously unexplored biosynthetic pathways and potentially provides a road map for future experimental characterization of poorly understood host-microbe and microbe-microbe interactions in the oral cavity that contribute to periodontitis.

The authors have declared no competing interest.

This study was funded by the university of Hong Kong internal fund (Seed Fund for Basic Research for New Staff).

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Ethics committee/IRB of Hong Kong/Hospital Authority Hong Kong West Cluster gave ethical approval for this work.

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