TY - JOUR
T1 - Site-specific deamidation of glutamine
T2 - A new marker of bone collagen deterioration
AU - Van Doorn, Nienke L.
AU - Wilson, Julie
AU - Hollund, Hege
AU - Soressi, Marie
AU - Collins, Matthew J.
PY - 2012/10/15
Y1 - 2012/10/15
N2 - Ratione: Non-enzymatic deamidation accumulates in aging tissues in vivo and has been proposed to be potentially useful as a molecular clock. The process continues post mortem, and here we explore the increase in levels of deamidation in archaeological collagen, as measured during Zooarchaeology by Mass Spectrometry (ZooMS) analysis. Methods: With the high sensitivity of current generation mass spectrometers, ZooMS provides a non-destructive and highly cost-effective method to characterise collagen peptides. Deamidation can be detected by mass spectrometry as a +0.984 Da mass shift; therefore, aside from its original purpose, peptide mass-fingerprinting for bone identification, ZooMS concurrently yields a 'thermal indicator' of the samples. RESULTS: By analysis of conventional ZooMS spectra, we determined the deamidation rate for glutamine residues in 911 bone collagen samples from 50 sites, with ages varying from medieval to Palaeolithic. The degree of deamidation was compared to diagenetic parameters and nearby sequence properties. CONCLUSIONS: The extent of deamidation was found to be influenced more by burial conditions and thermal age than, for example, chronological age, the extent of bioerosion or crystallinity. The method lends itself mostly to screening heterogenic deposits of bone to identify outliers.
AB - Ratione: Non-enzymatic deamidation accumulates in aging tissues in vivo and has been proposed to be potentially useful as a molecular clock. The process continues post mortem, and here we explore the increase in levels of deamidation in archaeological collagen, as measured during Zooarchaeology by Mass Spectrometry (ZooMS) analysis. Methods: With the high sensitivity of current generation mass spectrometers, ZooMS provides a non-destructive and highly cost-effective method to characterise collagen peptides. Deamidation can be detected by mass spectrometry as a +0.984 Da mass shift; therefore, aside from its original purpose, peptide mass-fingerprinting for bone identification, ZooMS concurrently yields a 'thermal indicator' of the samples. RESULTS: By analysis of conventional ZooMS spectra, we determined the deamidation rate for glutamine residues in 911 bone collagen samples from 50 sites, with ages varying from medieval to Palaeolithic. The degree of deamidation was compared to diagenetic parameters and nearby sequence properties. CONCLUSIONS: The extent of deamidation was found to be influenced more by burial conditions and thermal age than, for example, chronological age, the extent of bioerosion or crystallinity. The method lends itself mostly to screening heterogenic deposits of bone to identify outliers.
UR - http://www.scopus.com/inward/record.url?scp=84866096044&partnerID=8YFLogxK
U2 - 10.1002/rcm.6351
DO - 10.1002/rcm.6351
M3 - Journal article
C2 - 22956324
AN - SCOPUS:84866096044
SN - 0951-4198
VL - 26
SP - 2319
EP - 2327
JO - Rapid Communications in Mass Spectrometry
JF - Rapid Communications in Mass Spectrometry
IS - 19
ER -