The type of bacteria involved in human decomposition can change over time, according to new research published October 30th in the open-access journal PLOS ONE, by Aaron Lynne and colleagues at Sam Houston State University and Baylor College of Medicine.
A corpse is far from dead when viewed as an ecosystem for tiny bugs and microorganisms. Bacteria can take some credit for driving the natural process of human decomposition, but we know little about the diversity of bacterial species involved. Previous studies have been unfortunately limited to the traditional approach of culturing bacteria, whereas the vast majority of bacteria residing in the human body cannot actually be cultured experimentally.
To help address this problem, the authors studied the decomposition of two human cadavers under natural conditions. They assessed bacterial biodiversity using a gene sequencing method of analyzing bacterial DNA, rather than relying on traditional culture methods. This sequencing method allowed them to measure bacterial genes present in any given region of the cadaver, giving them a high-throughput way of mapping out an entire microbial community at two different time points.
They found that these bacterial communities were different between the two bodies and between regions on the same body, and these communities changed over the time-course of decomposition. The authors suggest that bacterial communities may be following specific, changing patterns as a corpse moves through its natural stages of decomposition. This gene sequencing approach may be a valuable tool for further dissecting the role of bacteria in human decomposition. Lynne expands, "This study is the first to catalogue bacteria present internally at the onset and end of the bloat stage of human decomposition. Ultimately, we hope to come up with a cumulative systems approach to look at decomposition in a way that might complement existing forensic models at determining the post-mortem interval (time since death)."
Citation: Hyde ER, Haarmann DP, Lynne AM, Bucheli SR, Petrosino JF (2013) The Living Dead: Bacterial Community Structure of a Cadaver at the Onset and End of the Bloat Stage of Decomposition. PLoS ONE 8(10): e77733. doi:10.1371/journal.pone.0077733
Financial Disclosure: Funding for this project was provided by Sam Houston State University in the form of an Enhancement Research Grant and by Baylor College of Medicine through the Alkek Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing Interest Statement: The authors have declared that no competing interests exist.
PLEASE LINK TO THE SCIENTIFIC ARTICLE IN ONLINE VERSIONS OF YOUR REPORT (URL goes live after the embargo ends): http://dx.plos.org/10.1371/journal.pone.0077733
Disclaimer: This press release refers to upcoming articles in PLOS ONE. The releases have been provided by the article authors and/or journal staff. Any opinions expressed in these are the personal views of the contributors, and do not necessarily represent the views or policies of PLOS. PLOS expressly disclaims any and all warranties and liability in connection with the information found in the release and article and your use of such information.
About PLOS ONE: PLOS ONE is the first journal of primary research from all areas of science to employ a combination of peer review and post-publication rating and commenting, to maximize the impact of every report it publishes. PLOS ONE is published by the Public Library of Science (PLOS), the open-access publisher whose goal is to make the world's scientific and medical literature a public resource.
All works published in PLOS ONE are Open Access. Everything is immediately availableŚto read, download, redistribute, include in databases and otherwise useŚwithout cost to anyone, anywhere, subject only to the condition that the original authors and source are properly attributed. For more information about PLOS ONE relevant to journalists, bloggers and press officers, including details of our press release process and our embargo policy, see the everyONE blog at http://everyone.plos.org/media.
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.