Identification of proteins from 4200-year-old skin and muscle tissue biopsies from ancient Egyptian mummies of the first intermediate period shows evidence of acute inflammation and severe immune response

Abstract

We performed proteomics analysis on four skin and one muscle tissue samples taken from three ancient Egyptian mummies of the first intermediate period, approximately 4200 years old. The mummies were first dated by radiocarbon dating of the accompany-\break ing textiles, and morphologically examined by scanning electron microscopy of additional skin samples. Proteins were extracted, separated on SDS–PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis) gels, and in-gel digested with trypsin. The resulting peptides were analysed using nanoflow high-performance liquid chromatography–mass spectrometry. We identified a total of 230 unique proteins from the five samples, which consisted of 132 unique protein identifications. We found a large number of collagens, which was confirmed by our microscopy data, and is in agreement with previous studies showing that collagens are very long-lived. As expected, we also found a large number of keratins. We identified numerous proteins that provide evidence of activation of the innate immunity system in two of the mummies, one of which also contained proteins indicating severe tissue inflammation, possibly indicative of an infection that we can speculate may have been related to the cause of death. This article is part of the themed issue ‘Quantitative mass spectrometry’.

Deep Time Paleoproteomics: Looking Forward

“…The field of paleoproteomics (here defined as the characterization of proteins from archeological and paleontological tissues using mass spectrometry [MS]) has grown exponentially since the first application of matrix-assisted laser desorption ionization (MALDI) MS to mammal remains 800–450 000 years old in 2000 . In the 22 years that followed, a variety of mass spectrometry-based methods have been used to investigate the preserved proteomic content of a diverse array of biological tissues (e.g., bones, teeth, baleen, turtle shell, mummified tissues), − objects (e.g., paintings, ethnologic objects, potsherds, parchment), − and species (e.g., mammoth, moa, giant beaver, whales, sea turtles). ,,,,,− However, the vast majority of these studies have focused on relatively young (<100 thousand years old) paleontological and archeological materials and remains. In this perspective, we discuss the development and progress of “deep time paleoproteomics (DTPp)”, here defined as MS characterization of material older than ∼1 million years (1 Ma).…”

Analysis of the Preserved Amino Acid Bias in Peptide Profiles of Iron Age Teeth from a Tropical Environment Enable Sexing of Individuals Using Amelogenin MRM

“…However, recent developments in high‐throughput, high‐resolution, mass spectrometry have led to greatly improved sensitivity and accuracy, which have now begun to be applied in the field of palaeopathology. For example, shotgun mass spectrometry has been used to identify highly antigenic proteins associated with bacteria such as gingipains in medieval human dental calculus, periodontic disease‐associated bacteria in Roman period dental calculus, establish the possible presence of Mycobacterium through buccal swabs of a 500‐year‐old Inca mummy, the possibility of infection in 360‐year‐old bone samples from Tokyo using a label‐free approach, and identification of proteins associated with tissue inflammation in skin samples of ≈4200‐year‐old mummies from Egypt . In the only other exploration of the endogenous dental paleoproteome to our knowledge, peptides associated with plague bacterium Yersinia pestis were able to be identified in 300‐year‐old dental pulp from a funeral site in France …”

Protein aggregate formation permits millennium-old brain preservation

“…IFs share some structural properties with collagens which have been shown to be among the most resistant proteins, permitting detection from fossilized bones of 68 Myr Tyrannosaurus rex. Collagens were shown to undergo a range of post-translational modifications in mummified tissues [71,72]. Of these, the involvement of lysine is dominant leading to a series of rearrangements, dehydration and fragmentation reactions which end up as complex, cross-linked structures [65,71].…”