Project description:In search of markers for protein aging, we used an extraordinary test case of human bones from the excavations sites of Pompei and Herculaneum (79 AD), analyzed by a shotgun proteomic approach using LC-MS/MS. Human bones from Scalandrone Bay (II sec AD, another volcanic area, yet not related to Vesuvius eruption were also analysed for the comparison of the PTMs provoked from a volcanic ground to an almost coeval standard burial condition. In addition, already published archaeological bones, approximately 17 centuries younger than the test case, were used as control samples. Deamidation of asparagine and glutamine was examined as a now widely considered aging molecular marker. Deamidation profile was quite robust for samples with a similar age whereas the fewer proteins were detected, the more degraded the sample were found to be. Positional investigation of deamidation in the polypeptide sequence of collagen type I revealed that some zones are more susceptible to deamidation than others. Back bone cleavage analysis confirmed that some zones apart from deamidation are more susceptible to spontaneous hydrolysis too. Analysis of post-translational modifications showed higher advanced glycation products of lysine and arginines in the samples of Pompeii and Herculaneum. Furthermore, oxidative products of methionine, histidine and the conversion of ST to glycine were also detected. Interestingly, multiple oxidation products of proline and dehydration of hydroxyproline were detected for the first time, turning the scientific interest to this amino acid (P), which is usually ignored due to its natural conversion to hydroxyproline. As a matter of fact, we can observe that collagen degradation in bones from Pompeii and Herculaneum underwent different degradation processes.