Aquatic Decomposition of Mammalian Corpses: A Forensic Proteomic Approach

Methods currently
available to estimate the postmortem submerged interval
(PMSI) of cadavers in water suffer from poor
accuracy, being mostly based on morphological examination of the remains.
Proteins present within bones have recently attracted more attention
from researchers interested in the estimation of the postmortem interval (PMI) in terrestrial environments. Despite the great potential
of proteomic methods for PMI estimation, their application to aquatic
environments has not yet been explored. In this study, we examined
whether four different types of aquatic environment affected the proteome
of mice bones with increasing PMSIs. Results showed that increasing
PMSIs can influence the protein abundances more than the different
types of water. In particular, the abundance of the muscle protein
fructose-bisphosphate aldolase A constantly decreased with increasing
PMSIs. Additionally, the protein peptidyl-prolyl cis–trans
isomerase showed a significant decrease between controls and aquatic
environments. Furthermore, the coagulation factor VII was deamidated
only in submerged samples and not in terrestrial controls. Finally,
fetuin-A was significantly more deamidated in pond water compared
to the other aquatic environments. Overall, this study identified
novel potential biomarker candidates that would be useful for the
estimation of the PMSI and for the characterization of the type of
water involved in criminal investigations.