Oral microbial diversity in 18th century African individuals from South Carolina.

As part of the Anson Street African Burial Ground Project, we characterized the oral microbiomes of twelve 18th century African-descended individuals (Ancestors) from Charleston, South Carolina, USA, to study their oral health and diet. We found that their oral microbiome composition resembled that of other historic (18th-19th century) dental calculus samples but differed from that of modern samples, and was not influenced by indicators of oral health and wear observed in the dentition. Phylogenetic analysis of the oral bacteria, Tannerella forsythia and Pseudoramibacter alactolyticus, revealed varied patterns of lineage diversity and replacement in the Americas, with the Ancestors carrying strains similar to historic period Europeans and Africans. Functional profiling of metabolic pathways suggested that the Ancestors consumed a diet low in animal protein. Overall, our study reveals important insights into the oral microbial histories of African-descended individuals, particularly oral health and diet in colonial North American enslavement contexts.