Researchers at Harvard University have found that bacteria from Neanderthal teeth could inform the development of new antibiotics. The findings appear in Science.
The team examined DNA from the dental plaque of 12 Neanderthals, 34 ancient Homo sapiens, and 18 modern humans in Europe and Africa spanning roughly 100,000 years. This broad sampling sheds light on the evolution of the oral microbiome, the vast array of microscopic life that inhabits the mouth and can be preserved in tartar.
From the data, the scientists focused on two bacterial species within the Chlorobi genus identified in seven individuals. These previously unknown species showed genetic similarity to Chlorobium limicola, a bacterium associated with spring environments near caves. Researchers suggest that people living in cave-adjacent habitats may have introduced this bacteria into their drinking water, reflecting how environment can influence microbial exposure.
Remarkably, the Chlorobium species linked to tartar from people who lived in the last 10,000 years were nearly absent. Shifts in how often Chlorobium appeared appear to track changes in the lifestyle and living patterns of ancient human populations.
The researchers also investigated biosynthetic gene clusters BGCs. By introducing these gene clusters into live bacteria, they observed the production of two new proteins involved in photosynthesis. Such discoveries could eventually guide the discovery of new antibiotics through novel biosynthetic pathways.
As one team member noted, bacteria are the source of most antibiotics available today, and there has been little advancement in discovering new antibiotic classes in recent years. The new methods enable exploration for antibiotic-producing BGCs in historical samples, expanding the search for future therapies (Harvard press release, 2024).