Microbial succession in human tissues postmortem: insights from 2bRAD-M sequencing.

Area of Science:

• Microbiology
• Forensic Science
• Thanatomicrobiome Research

Background:

• Microbial communities are vital for decomposition, but human internal organ thanatomicrobiome patterns are underexplored.
• Previous studies focused on animal models or limited human sites (gut, skin), leaving gaps in postmortem microbial dynamics.
• Understanding postmortem microbial succession is crucial for forensic science and ecological research.

Purpose of the Study:

• To profile microbial succession across seven human tissues at various postmortem intervals (PMIs).
• To investigate the utility of 2bRAD-M sequencing for human thanatomicrobiome analysis.
• To identify potential microbial biomarkers for estimating PMI.

Main Methods:

• Utilized 2bRAD-M sequencing technology for microbial profiling.
• Analyzed microbial communities across seven human tissues (heart, liver, spleen, lung, kidney, calf muscle, gut).
• Examined samples from various postmortem intervals and compared frozen versus unfrozen cadavers.

Main Results:

• Significant variations in microbial community composition were observed across different organs and decomposition stages.
• Proteobacteria dominated early postmortem, followed by Firmicutes.
• Frozen and unfrozen cadavers showed divergent microbial shifts in the liver and spleen, with limited variation in other tissues.

Conclusions:

• Human thanatomicrobiome exhibits complex, organ-specific microbial trajectories.
• Microbial signatures show potential as biomarkers for estimating postmortem intervals.
• This study enhances understanding of postmortem microbial dynamics and forensic methodologies.