are you a monosaccharide? ive never meant anyone as sweet as you😣 footage from hybrid biomedical "Paleoproteomics, the study of ancient proteins, is a rapidly growing field at the intersection of molecular biology, paleontology, archaeology, paleoecology, and history. Paleoproteomics research leverages the longevity and diversity of proteins to explore fundamental questions about the past. While its origins predate the characterization of DNA, it was only with the advent of soft ionization mass spectrometry that the study of ancient proteins became truly feasible. Technological gains have allowed increasing opportunities to better understand preservation, degradation, and recovery of the rich bioarchive of ancient proteins found in the archaeological and paleontological records. Growing from a handful of studies in the 1990s on individual abundant ancient proteins, paleoproteomics today is an expanding field with diverse applications ranging from the taxonomic identification of highly fragmented bones and shells and the phylogenetic resolution of extinct species to the exploration of past cuisines from dental calculus and pottery food crusts and the characterization of past diseases. More broadly, these studies have opened new doors in understanding past human–animal interactions, the reconstruction of past environments and environmental changes, the expansion of the hominin fossil record through large scale screening of nondiagnostic bone fragments, and the phylogenetic resolution of the vertebrate fossil record. Even with these advances, much of the ancient proteomic record still remains unexplored. Here we provide an overview of the history of the field, a summary of the major methods and applications currently in use, and a critical evaluation of current challenges. We conclude by looking to the future, for which innovative solutions and emerging technology will play an important role in enabling us to access the still unexplored “dark” proteome, allowing for a fuller understanding of the role ancient proteins can play in the interpretation of the past. Although proteins decay, nitrogen recycling is not completely efficient, and in protected environments (e.g., bones, teeth, eggshell) proteins can persist for millions of years or more. Protein fragments are recognizable in fossils (e.g., seeds, b0ne), worked biological remains, (e.g., wood, textiles, archaeological and art historical artifacts), as residues on cooking vessels, and also entrapped within soils and sediments. There is more protein nitrogen in this “d34d pool” than there is in all the living cells on earth. Encoded by DNA, proteins pack the same amount of sequence information into approximately one-sixth the number of atoms. For example, a 50 bp fragment of DNA (30.4 kDa) has a larger mass than many intact proteins, including β-lactoglobulin (18.4 kDa), hemoglobin (15.9 kDa), and amelogenin (24.1 kDa). Protein folding and aggregation further protect proteins from chemical attack and facilitate entrapment. With fewer atoms, fewer chemical bonds, and a more compact structure, proteins consequently fall apart more slowly than DNA. However, the greater range of reactive species and our limited ability to recover direct information about their state of decay mean that ancient proteins stretch the limits of our understanding of decay processes and diagenetic modification. Yet the results are hardly esoteric, as modifications associated with ancient proteins have relevance for understanding aging and diseased tissues, and are induced during the production and consumption of protein-containing materials and foods." #biology #guthealth #gutmicrobiome