This paper reports on a study of the microbial breakdown of 36 terrestrial human cadavers in three locations, showing that a phylogenetically distinct, interdomain microbial network forms during decomposition despite selection effects of location, climate, and season, discussing implications for microbial forensic science and for the ability to aid determination of the time since death.
This study tracks 36 terrestrial human cadavers in three locations and shows that a phylogenetically distinct, interdomain microbial network assembles during decomposition despite selection effects of location, climate and season. Microbial breakdown of organic matter is one of the most important processes on Earth, yet the controls of decomposition are poorly understood. Researchers generated a metagenome-assembled genome library from cadaver-associated soils and integrated it with metabolomics data to identify links between taxonomy and function. This universal network of microbial decomposers is characterized by cross-feeding to metabolize labile decomposition products. The key bacterial and fungal decomposers are rare across non-decomposition environments and appear unique to the breakdown of terrestrial decaying flesh, including humans, swine, mice and cattle, with insects as likely important vectors for dispersal. The observed lockstep of microbial interactions further underlies a robust microbial forensic tool with the potential to aid predictions of the time since death. (Published Abstract Provided)