Isolation and characterization of live yeast cells from ancient vessels as a tool in bio-archeology

Abstract

34Ancient fermented food has been studied based on recipes, residue analysis and ancient-DNA 35 techniques and reconstructed using modern domesticated yeast. Here, we present a novel 36 approach. We hypothesize that enriched yeast populations in fermented beverages could have 37 become the dominant species in storage vessels and the descendants of these yeast could be 38 isolated and studied long after. To this end, using a pipeline of yeast isolation from clay vessels 39 developed here, we screened for yeast cells in beverage-related and non-related ancient vessels 40 and sediments, from several archeological sites. We found that yeast cells could be successfully 41 isolated specifically from clay containers of fermented beverages. Genomic analysis revealed that 42 these yeast are similar to those found in traditional African beverages. Phenotypically, they grow 43 similar to modern-beer producing yeast. Both strongly suggesting that they are descendants of 44 the original fermenting yeast. These findings provide modern microorganisms as a new tool in 45 bio-archeology. 46Importance 47 So far, most of the study of ancient organisms was based mainly on the analysis of ancient DNA. 48Here we show that it is possible to isolate and study microorganisms, yeast in this case, from 49 thousands of years old clay vessels, used for fermentation. We demonstrate that it is highly likely 50 that these cells are descendants of the original yeast strains which participated in the fermentation 51 process and were absorbed into the pottery vessels. Moreover, we characterize the isolated yeast 52 their genome and the beer they produce. These results open new and exciting avenues in the 53 study of domesticated microorganisms and contribute significantly to the fields of bio and 54 experimental -archeology that aims to reconstruct ancient artifacts and products.55 56 57 58 109 5containers. In contrast, we could not isolate any live yeast from the control vessels which were 110 filled with filtered beer, nor were yeast cells detected by electron microscopy (Fig. 1A, left panel).

Relevance of Ancient Chinese Wine Ware Representation Design and Cultural Characteristics Based on Machine Learning and Semiotic Theory

“…Westerners believe that different shapes of wine vessels have a crucial influence on the taste and temperature of wine [18]. Different wines use different drinking utensils and consequently produce different wine cultures, but it all exists in the mainstream of development.…”

Water is a preservative of microbes

“…Whereas attempts have not always been made to culture microbes from ancient sugar-rich materials-that are effectively highly concentrated aqueous solutions-viable microbes have been retrieved in some cases. Although sugars were not analysed, yeasts have been cultured from clay beer vessels that were 5000 years old (Aouizerat et al, 2019(Aouizerat et al, , 2020Br€ ussow, 2020). Whereas Yashina et al (2012) regenerated plants from 30 000-year-old fruits (and no attempt was made to culture viable microbes), these higher plants can survive within permafrost then it is likely that these high-sugar fruits were associated with preserved microbes; life forms that are generally more simple and more robust.…”

Endurance of extremely prolonged nutrient prevention across kingdoms of life

“…Support for this notion is the finding of yeast strains that survived for thousands of years in the micro-pores of clay vessels that contained beer. We managed to revive these yeast cells and rebrew beer from them (Aouizerat et al, 2019b). Although the exact mechanisms that lead to the survival of these cells remain a mystery (including the question of whether yeast ll OPEN ACCESS 6 iScience 24, 102745, July 23, 2021 iScience Review sporulation was involved), GASP-like phenotypes and adaptation to stress could contribute to this phenomenon.…”