Discipline: Biological Sciences
Subcategory: Cell and Molecular Biology
Session: 2
Room: Exhibit Hall A
Elizabeth Michaelis - Delaware State Univerisity
Co-Author(s): Gulnaz Javan, Alabama State University, Montgomery, AL; LaTia Scott, Delaware State University, Dover, DE
Shortly after an organism dies, the corpse begins to decay and microorganisms become progressively abundant. These stages of decomposition can be used to estimate the time that has elapsed after death, postmortem interval (PMI). More recently, the thanatomicrobiome (microorganisms found in internal organs after death) have been used to estimate PMI but with obvious limitations. To date, there is no published data involving zero postmortem interval within human cadavers from actual cases due to set experimental design. In this experiment, swine was used as alternative model which undergoes similar stages of decomposition as humans to evaluate liver and spleen thanatomicrobiome. We hypothesize that at zero PMI, both liver and spleen will test positive for microbes but liver will exhibit higher microbial diversity than spleen due to its size and various functions. We obtained liver and spleen organ tissue from 15 deceased swine and Sanger sequencing was performed utilizing the hypervariable V4 region of the 16S rRNA gene. The results showed that there were no microbes detected in swine liver and spleen tissues; thus, no microbial diversity. This suggests that the swine internal organs are sterile at zero PMI. The results were not anticipated but consistent with a long held belief that human internal organs are sterile in living hosts due to uncultivable microorganisms. Additionally, swine used for this experiment were for human consumption and may have been treated with antibiotics. The data collected from this experiment provide information regarding microorganisms during the first few moments following death and present swine as viable alternative thanatos model. These preliminary results are significant due to the difficulty to survey the thanatomicrobiome during this period among human cadaver cases. Future research involves understanding swine thanatomicrobiome beyond zero PMI to identify possible trends. References: Ford, W W. ‘On the Bacteriology of Normal Organs.’ The Journal of hygiene vol. 1,2 (1901): 277-84. doi:10.1017/s0022172400000231; Javan, Gulnaz T et al. ‘Human Thanatomicrobiome Succession and Time Since Death.’ Scientific reports vol. 6 29598. 14 Jul. 2016, doi:10.1038/srep29598
Funder Acknowledgement(s): I thank Dr. G. Javan and Dr. L. Scott for their help. Funding was provided by an NSF/ HBCU-UP grant to Dr. LaTia Scott.
Faculty Advisor: LaTia Scott, lescott@desu.edu
Role: I completed DNA extractions and PCRs.