Paleoproteomics has been successfully utilised for the species-level identification of osseous material in the archaeological record. This technique is underpinned by the intrinsic link between amino acid sequences and genome sequences, and the survivability of proteins over longer periods of time. Current standard in the field is the use of microscopy for identification of morphological features, however this approach is hindered by sample age and preservation quality. This study aims to develop a molecular-based approach for the species-level identification of plant fibres in ancient Egyptian mummification bandages from the remains of Mer-Neith-it-es (NMR.29), a 26th Dynasty (ca. 664 – 525 BCE) mummified individual housed in the Nicholson Collection of the Chau Chak Wing Museum, The University of Sydney, Australia.
Modern surrogate cotton and flax samples were used as reference for both microscopic and proteomic analysis. Microscopy was performed using a Phenom XL Benchtop Scanning Electron Microscope.
An initial shotgun proteomics workflow was employed to analyse the textile samples, followed by a targeted PRM approach for species-specific peptides. Briefly, this involved homogenising small (<10 mg) amounts of textile samples with liquid nitrogen in a mortar and pestle prior to FASP. Following in-gel trypsin digestion, resultant peptides were analysed using a Thermo Exploris 480 orbitrap mass spectrometer coupled to a Thermo Vanquish Neo liquid chromatography system.. Peptide-to-spectrum matching was performed using MSFragger against a curated database of plant protein sequences including those commonly used in textile production (Bamboo, subfamily Bambusoideae; Cotton, Gossypium sp.; and Flax, Linum usitatissimum). PRM data was analysed in Skyline.
Peptides were successfully identified from all textile pieces following the extraction protocol. Data will be presented on the species identification of the textile pieces. The success of both the microscopic and proteomic identification methods will be assessed in order to validate the use of destructive molecular-based approaches when non-destructive observational techniques are inconclusive.
The results of this study will generate valuable new information about the textiles used in the mummification process of a 26th Dynasty individual. There is existing literature indicating that the choice of flax or cotton in burial materials was often an indicator of societal prestige and status. Details of the identity of Mer-Neith-it-es remain cryptic despite intensive research, so any new information will add to our understanding of this individual.