A Microbial Time Capsule in Dental Plaque

Ancient microbiome analysis uncovered regional variation and evolutionary changes in oral microorganisms

To analyze the oral microbial composition of historical Japanese populations through dental calculus and compare it with modern samples.

285 oral microbial species were identified, showing clear differences between ancient and modern oral microbiomes.
Increased prevalence of Methanobrevibacter oralis, associated with periodontitis, was found in historical samples.
Regional variations were noted between mainland Japan and Okinawa in the prevalence of specific microbial taxa.
Distinct microbial lineages were associated with different historical periods, indicating demographic and lifestyle influences on oral microbial evolution.
Two major historical clades of M. oralis were identified, with clade membership linked to host sex and practices like ohaguro.