Bioluminescent bacteria have potential as a marker of drowning in seawater: two immersed cadavers retrieved near estuaries.
We detected numerous bioluminescent bacteria in blood samples from two cadavers that had been immersed in estuarine environments. Autopsy, diatomaceous and toxicological findings indicated death by drowning, which agreed with environmental aspects and the findings of police investigations. Bioluminescent bacteria appeared in blood samples cultured on selective agar containing 2%, 3% and 4% NaCl after about 18h. Blood from the left side of the heart, the right side of the heart and the femoral vein generated 7.0 x 10(2), 2.0 x 10(4) and 8.0 x 10(2) cfu/ml of blood (case 1), and 1.8 x 10(4), 1.1 x 10(3) and 2.5 x 10(1) cfu/ml (case 2) of bioluminescent colonies, respectively, in agar containing 4% NaCl. Homologous analysis based on the 16S rRNA gene also identified the bioluminescent colonies as Vibrio fischeri and V. harveyi, which normally inhabit seawater. This simple assay might serve as an additional indicator to support a conclusion of death by drowning together with the diatom test.
Kakizaki
Eiji
E
Section of Legal Medicine, Department of Social Medicine, Faculty of Medicine (Miyazaki Medical College), University of Miyazaki, Kiyotake-cho, Miyazaki, Japan. eijik@med.miyazaki-u.ac.jp
Kozawa
Shuji
S
Sakai
Masahiro
M
Yukawa
Nobuhiro
N
D015415:Biomarkers / Q000032:analysis; D001769:Blood / Q000382:microbiology; D004332:Drowning / Q000175:diagnosis*; D049429:Forensic Pathology; D006801:Humans; D049449:Luminescence; D008168:Lung / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012336:RNA, Ribosomal, 16S / Q000378:metabolism; D012623:Seawater; D013194:Staining and Labeling; D014733:Vibrio / Q000235:genetics / Q000302:isolation & purification*
D015415:Biomarkers; D012336:RNA, Ribosomal, 16S