From the ACS Press Room
Extracting Information from Ancient Teeth “Comparing the Use of Magnetic Beads with Ultrafiltration for Ancient Dental Calculus Proteomics”
important to apply methods that can extract the most information from minuscule samples. Although no gold-standard method for calculus analysis exists, filter-based techJournal of Proteome Research niques are often used, but they can be time There’s a surprising amount of information consuming and can introduce contaminants. stored in the hardened plaque, or calculus, So, teams led by Michael Buckley and Cherbetween teeth. And if that calculus belongs to yl Makarewicz wanted to see whether anoththe remains of a person who lived in ancient er method, called single-pot, solid-phasetimes, the information could reveal new in- enhanced sample preparation (SP3), could sights about the past. But the tiny samples improve the number and complexity of procan be difficult to work with. Now, in tein fragments that could be analyzed from ACS’ Journal of Proteome Research, scien- preserved plaque. tists apply a new method to this analysis, The researchers, led by Karren Palmer, apfinding more proteins than traditional ap- plied SP3 to the analysis of calculus from 153 ancient individuals dating from between proaches. st th The hu- the 1 and 4 century BCE. With SP3, functionalized magnetic beads grabbed onto proman mouth is tein fragments, making them easy to analyze full of in- by mass spectrometry. The researchers found that SP3 reliably increased the number of teresting molecules: unique protein fragments they could identify DNA and in samples, including smaller peptides that two other methods, ultrafiltration and acetone enzymes in saliva, precipitation, missed. SP3 was also easy to perform and less likely to introduce contamiproteins and lipids from bits of food stuck between nants than the other methods. Using this apteeth, the bacterial citizens of the oral micro- proach, the researchers identified fragments biome. Under the right conditions, those mol- of dairy proteins from the subjects’ diets, as ecules can be preserved in dental calculus for well as bacterial proteins that could shed thousands of years. Identifying the biomole- light on ancient diseases.
cules preserved within ancient plaque gives researchers clues about how our ancestors lived, what they ate, what diseases they had and more. However, there’s only so much plaque one can scrape off of old teeth, so it’s March 2021
The authors acknowledge funding from the European Research Council and the European Union’s Horizon 2020 research and innovation program.
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