Bacterial Succession of the Aquatic Necrobiome as an Indicator of Post Mortem Submersion Interval

The soft tissue decomposition of human remains has been extensively studied, resulting in identification of sequential morphological change and patterns of insect colonisation. These studies have led to formulae being derived for post mortem interval estimation. Despite 140,000 annual police investigations around the world involving water, much of the present knowledge is only applicable to terrestrial decomposition [1].

It is well documented that micro-organisms are involved in decomposition processes, and are ubiquitous in water sources and human bodies [2]. Investigating the sequential colonisation of a body by microorganisms in water as well as the bacterial migration from the gut may provide a useful method for estimating post mortem submersion interval (PMSI).

Matrix assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) has been described as a revolutionary new technique within the field of microbiology [3] and is expected to become the method of choice over other biochemical microbial identification techniques [4]. This study utilised MALDI-TOF MS as a rapid, inexpensive and sensitive method for identifying bacteria from a freshwater system.