Olakanye Ayodeji O, Nelson Andrew, Ralebitso-Senior T Komang
Department of Science, School of Science and Engineering, Teesside University, Borough Road, Middlesbrough, Teesside, TS1 3BX, United Kingdom.
Faculty of Health and Life Sciences, Northumbria University, Newcastle Upon Tyne, NE1 8ST, United Kingdom.
Forensic Sci Int. 2017 Jul;276:85-92. doi: 10.1016/j.forsciint.2017.04.024. Epub 2017 May 6.
A cadaver and dead plant organic matter, or litter, are rich energy sources that undergo a complex decomposition process, which impact the surrounding environmental microbiota. Advances in molecular microbiology techniques, with study of the 16S RNA genes, in particular, have highlighted the application of forensic ecogenomics in addressing key knowledge gaps. To investigate subsurface microbiome shifts as a novel tool to establish "postmortem microbial clock" and augment postmortem interval (PMI) and time-since-burial estimations, an in situ study with triplicate underground burials of piglets as human taphonomic proxies and Quercus robur leaf litter was monitored for 270 days. Changes in microbial community structure and composition were related directly to changes in seasonal temperature, with microbial shifts more pronounced during the summer. For example, Methylococcaceae could be used as seasonal bacterial indicators, from winter to summer, in establishing postmortem microbial clock for this site. Furthermore, Methylophilaceae (Methylophilales order) and Anaerolineaceae would differentiate for the piglet and leaf litter soils, respectively, 180 days after internment.
尸体和死亡的植物有机质，即枯枝落叶，是丰富的能量来源，它们会经历一个复杂的分解过程，这会影响周围环境中的微生物群。分子微生物学技术的进步，特别是对16S RNA基因的研究，突出了法医生态基因组学在填补关键知识空白方面的应用。为了研究地下微生物群落的变化，将其作为建立“死后微生物时钟”以及延长死后间隔时间（PMI）和入土时间估计的一种新工具，进行了一项原位研究，以仔猪作为人类尸体腐烂的替代物进行了三次地下埋葬，并对欧洲栎树叶凋落物进行了270天的监测。微生物群落结构和组成的变化与季节温度的变化直接相关，夏季微生物的变化更为明显。例如，甲基球菌科可以作为从冬季到夏季的季节性细菌指标，用于建立该地点的死后微生物时钟。此外，在埋葬180天后，嗜甲基菌科（嗜甲基菌目）和厌氧绳菌科将分别区分仔猪和落叶土壤中的微生物。
