Project description:To investigate dairy consumption in ancient Mongolia, we analysed dental calculus samples from four Late Bronze Age (LBA, 1500-1000 BCE) individuals for proteomic evidence of milk proteins. As many archaeological sites before Mongolia's Iron Age suffer from a dearth of occupational materials, looking to biomolecular markers of dietary intake can open new investigational avenues into ancient economies. In this case, we use a previously established method of extracting proteins from calculus to explore the consumption of dairy products at LBA Khirigsuur sites in northern Mongolia's Hovsgol Aimag. Seven of nine individual's calculus contained peptides from the whey protein Beta-lactoglobulin from Ovis, Capra hircus, Bos, and general Bovidae species. Aside from proteomics, these and 16 other individuals from the site were analysed for aDNA. We found that 18 of the 20 were primarily from one genetic ancestral group, and Ancient North Eurasian (ANE). One of the outliers represents a combination of ANE and Western Steppe Herder (WSH), with the other a combination of ANE and Eastern Asian (EE). This finding, while important in its own right, evidences the earliest known dairy consumption in Mongolia, and supports a widely held assumption that pastoralism was a primary subsistence strategy in the ancient Eastern Steppes. The combined proteomic and DNA evidence suggest that Western Steppe dairy animals and technology entered Mongolia before genetic admixture.
Project description:Archaeological dental calculus has emerged as a rich source of ancient biomolecules, including proteins. Previous analyses of proteins extracted from ancient dental calculus revealed the presence of the dietary milk protein β-lactoglobulin, providing direct evidence of dairy consumption in the archaeological record. However, the potential for calculus to preserve other food-related proteins has not yet been systematically explored. Here we analyse shotgun metaproteomic data from 100 archaeological dental calculus samples ranging from the Iron Age to the post-medieval period (8thC BC - 19thC AD) in Britain, as well as dental calculus from contemporary dental patients and recently deceased individuals, to characterise the range and extent of dietary proteins preserved in dental calculus. In addition to milk proteins, we detected proteomic evidence of foodstuffs such as cereals and plant products, as well as the digestive enzyme salivary amylase. We discuss the importance of optimized protein extraction methods, data analysis approaches, and authentication strategies in the identification of dietary proteins from archaeological dental calculus. Our ability to detect dietary proteins, although limited, demonstrates the potential of these methods to robustly identify foodstuffs in the archaeological record that are under-represented due to their poor preservation.
Project description:Dental calculus is becoming a crucial material in the study of past populations, with increasing interest in its proteomic and genomic content. Here we suggest further development of protocol for analysis of ancient proteins and a combined approach for subsequent ancient DNA extraction. We tested the protocol on recent teeth. We then applied the optimised protocol to ancient teeth to limit the destruction of calculus, as it is a precious and irreplaceable source of dietary, microbiological, and ecological information in the archaeological context. Finally, the applicability of the protocol was proven on samples of ancient calculus.
Project description:Detailed investigation of extremely severe pathological conditions present in ancient human skeletons is important because they can illuminate the breadth of potential interactions between humans and disease etiologies in the past. Here, we applied palaeoproteomics to investigate the bacterial pathogenic factors and host defense response to an ancient human skeletal individual with severe oral pathology. This female skeleton, from the Okhotsk period (i.e., 5th–13th century) of northern Japan, poses abnormal deposition of large amounts of dental calculus and oral dysfunction due to severe periodontal disease. A shotgun mass-spectrometry analysis identified 81 human proteins and 15 bacterial proteins from her calculus. Two pathogenic or bio-invasive proteins originating from two of the three “red complex” bacteria, the core species associated with severe periodontal disease in modern humans, as well as additional two bio-invasive proteins of periodont-associated bacteria were identified. Human proteins associated with the defense response system were identified, but their proportion was mostly similar to that reported in ancient and modern human individuals with lower calculus deposition. These results suggest that the bacterial etiology was similar and the host defense response was not necessarily higher in ancient individuals with abnormal deposition of large amounts of dental calculus.
Project description:Archaeological dental calculus has emerged as a rich source of ancient biomolecules, including proteins. Previous analyses of proteins extracted from ancient dental calculus revealed the presence of the dietary milk protein β-lactoglobulin, providing direct evidence of dairy consumption in the archaeological record. However, the potential for calculus to preserve other food-related proteins has not yet been systematically explored. Here we analyse shotgun metaproteomic data from 100 archaeological dental calculus samples ranging from the Iron Age to the post-medieval period (eighth century BC to nineteenth century AD) in England, as well as 14 dental calculus samples from contemporary dental patients and recently deceased individuals, to characterize the range and extent of dietary proteins preserved in dental calculus. In addition to milk proteins, we detect proteomic evidence of foodstuffs such as cereals and plant products, as well as the digestive enzyme salivary amylase. We discuss the importance of optimized protein extraction methods, data analysis approaches and authentication strategies in the identification of dietary proteins from archaeological dental calculus. This study demonstrates that proteomic approaches can robustly identify foodstuffs in the archaeological record that are typically under-represented due to their poor macroscopic preservation.