Sequence analysis of bacterial DNA in the colon and stomach of the Tyrolean Iceman

Abstract

The male human body found in an Alpine glacier on September 19, 1991 ("Tyrolean Iceman") has, for the first time in history, given scientists a chance to perform detailed anatomical, histological, and molecular investigations on the organs of a person from the Neolithic Age (5350-5100 B.P.). In the present study, tissue samples aseptically taken from the stomach and the colon of the mummy were utilized for DNA extraction, and the DNA was PCR-amplified, using primer pairs designed to bind to fragments of the 16s ribosomal RNA gene (16s rDNA) of a broad range of bacteria. The PCR products were cloned in plasmid vectors, and the recombinant clones (amplicons) were sequenced. The sequence data were finally used for scanning data libraries containing the corresponding sequences of present-day bacteria, to infer the putative ecophysiology of the ancient ones. The same procedure was repeated on some fragments of grass from the clothing found near the corpse. These fragments were taken as a control of the microbiological situation of the glacier. The results show that the flora of the Iceman's stomach is entirely composed of Burkholderia pickettii, an organism commonly found in aquatic habitats. The colon, on the other hand, contains several members of the fecal flora of humans, such as Clostridium perfringens, C. ghonii, C. sordellii, Eubacterium tenue, and Bacteroides sp. The Iceman's colon, however, was found to contain, rather unexpectedly, also some members of the genus Vibrio. The results are discussed in light of what is known about the preservation of microbial DNA at the Iceman's site and of previous parasitological studies performed on the Iceman himself and on human coprolites.

Microbial survey of the mummies from the Capuchin Catacombs of Palermo, Italy: biodeterioration risk and contamination of the indoor air

“…A particularly interesting sector within this field is the study of ancient microorganisms, bacteria, filamentous fungi, yeast, algae, protozoans, and viruses. The analyses of ancient microorganisms DNA in ancient human remains are contributing to the understanding of various issues such as the spread of diseases (Zink et al, 2002(Zink et al, , 2003Fernandez, 2012), the mummification processes , and the effect of diet and hygiene conditions on historical human populations (Cano et al, 2000). Nevertheless, this study is not focused on ancient microorganisms, but on those opportunistic microorganisms able to colonize and deteriorate the preservation of ancient bodies.…”

New directions and interactions in metagenomics research

“…Sequence analysis of ancient DNA is challenging, because of the technological obstacles of degraded and chemically degraded molecules, and contamination with modern DNA (Hofreiter et al, 2001;Paabo et al, 2004), although a recent report that 'crystal aggregates' within fossils provide higher-quality DNA than the surrounding bone indicates that progress is being made in this technology. The ability to use metagenomics to probe ancient DNA will no doubt be exploited in the near future to analyse bacteria proposed as ancient, for example Micrococcus luteus preserved in 120million-year-old amber (Greenblatt et al, 2004), and the microbes detected in the stomach and colon of the Neolithic 'Tyrolean Iceman' (Cano et al, 2000). The Iceman's stomach flora appeared to consist entirely of Burkholderia pickettii, normally an inhabitant of aquatic systems.…”

Molecular characterization of a pre‐Columbian mummy and in situ coprolite

“…The results are finally evaluated for the (at least partial) consistency of the (putative) bacterial type and distribution with that of living persons. This criterion was applied to the study of the intestinal microflora of the Tyrolean Iceman (Cano et al, 2000) and to the present and past (Ubaldi et al, 1998) investigations on the mummy of the Museo Nazionale di Antropologia ed Etnologia of Florence.…”