Woide D.,Helmholtz Center Munich |
Zink A.,Institute for Mummies and the Iceman |
Thalhammer S.,Helmholtz Center Munich
American Journal of Physical Anthropology | Year: 2010
The study of ancient DNA plays an important role in archaeological and palaeontological research as well as in pathology and forensics. Here, we present a new tool for ancient DNA analysis, which overcomes contamination problems, DNA degradation, and the negative effects of PCR inhibitors while reducing the amount of starting target material in the picogram range. Ancient bone samples from four Egyptian mummies were examined by combining laser microdissection, conventional DNA extraction, and low-volume PCR. Initially, several bone particles (osteons) in the micrometer range were extracted by laser microdissection. Subsequently, ancient DNA amplification was performed to verify our extraction method. Amelogenin and β-actin gene specific fragments were amplified via low-volume PCR in a total reaction volume of 1 μl. Results of microdissected mummy DNA samples were compared to mummy DNA, which was extracted using a standard DNA extraction method based on pulverization of bone material. Our results highlight the combination of laser microdissection and low-volume PCR as a promising new technique in ancient DNA analysis. © 2010 Wiley-Liss, Inc. Source
Hall E.K.,University of Vienna |
Singer G.A.,University of Vienna |
Polzl M.,University of Vienna |
Hammerle I.,University of Vienna |
And 5 more authors.
ISME Journal | Year: 2011
Stoichiometry of microbial biomass is a key determinant of nutrient recycling in a wide variety of ecosystems. However, little is known about the underlying causes of variance in microbial biomass stoichiometry. This is primarily because of technological constraints limiting the analysis of macromolecular composition to large quantities of microbial biomass. Here, we use Raman microspectroscopy (MS), to analyze the macromolecular composition of single cells of two species of bacteria grown on minimal media over a wide range of resource stoichiometry. We show that macromolecular composition, determined from a subset of identified peaks within the Raman spectra, was consistent with macromolecular composition determined using traditional analytical methods. In addition, macromolecular composition determined by Raman MS correlated with total biomass stoichiometry, indicating that analysis with Raman MS included a large proportion of a cell's total macromolecular composition. Growth phase (logarithmic or stationary), resource stoichiometry and species identity each influenced each organism's macromolecular composition and thus biomass stoichiometry. Interestingly, the least variable peaks in the Raman spectra were those responsible for differentiation between species, suggesting a phylogenetically specific cellular architecture. As Raman MS has been previously shown to be applicable to cells sampled directly from complex environments, our results suggest Raman MS is an extremely useful application for evaluating the biomass stoichiometry of environmental microorganisms. This includes the ability to partition microbial biomass into its constituent macromolecules and increase our understanding of how microorganisms in the environment respond to resource heterogeneity. © 2011 International Society for Microbial Ecology All rights reserved. Source
Structural and functional characterisation of the chlorite dismutase from the nitrite-oxidizing bacterium " Candidatus Nitrospira defluvii": Identification of a catalytically important amino acid residue
Kostan J.,University of Vienna |
Sjoblom B.,University of Vienna |
Maixner F.,University of Vienna |
Maixner F.,Institute for Mummies and the Iceman |
And 7 more authors.
Journal of Structural Biology | Year: 2010
Chlorite dismutase (Cld) is a unique heme enzyme which transforms chlorite to chloride and molecular oxygen (reaction: ClO2-→Cl-+O2). Since bacteria with Cld play significant roles in the bioremediation of industrially contaminated sites and also in wastewater treatment, it is of high interest to understand the molecular mechanism of chlorite detoxification. Here we investigate a highly active Cld from Candidatus Nitrospira defluvii (NdCld), a key nitrifier in biological wastewater treatment, using a comprehensive structural, biochemical and bioinformatics approach. We determined the crystal structure of Cld from Candidatus Nitrospira defluvii and showed that functional NdCld is a homopentamer possessing a fold found in other Clds and Cld-like enzymes. To investigate the Cld function in more detail, site-directed mutagenesis of a catalytically important residue (Arg173) was performed and two enzyme mutants were structurally and biochemically characterized. Arginine 173 is demonstrated to play a key role in (i) controlling of ligand and substrate access and binding and (ii) in chlorite dismutation reaction. The flexible residue modulates the electrostatic potential and size of the active site entrance and might be involved in keeping transiently formed hypochlorite in place for final molecular oxygen and chloride formation. Furthermore, using a structure-based sequence alignment, we show that the residue corresponding to Arg173 is conserved in all known active forms of Cld and propose it as a marker for Cld activity in yet uncharacterized Cld-like proteins. Finally, our analysis indicates that all Clds and Cld-like enzymes employ a non-covalently bound heme as a cofactor. © 2010 Elsevier Inc. Source
News Article | August 18, 2016
Since Otzi the Iceman was discovered on a glacier near the Italian-Austrian border in 1991, his mummified body has been a constant source of study, with researchers working laboriously to discover whatever they can about one of humanity's ancestors. Now, researchers have discovered yet another detail about the iceman: what he wore when he died. Researchers had a solid idea about many aspects of Otzi's life, such as how he died and what his diet consisted of prior to his end, but what he had on at the time continued to elude them. Otzi was found with various leather clothing when he was discovered all those years ago, but due to the limitations of DNA study at the time, they couldn't narrow what he wore down to the species level. Now, thanks to advancements made in that field, not only have researchers discovered what types of leather Otzi wore, but the discovery has revealed quite a bit about his lifestyle. The findings, published in Scientific Reports, revealed that Otzi's clothes were comprised of at least five five different animals when he met his end. – A coat of many fragments, incorporating both sheep and goat skin To reach this conclusion, researchers analyzed the leathers' mitochondrial DNA — the separate, smaller genome found in the tiny compartments that turn food into energy inside living cells. "We analyzed nine samples and for each one, we were able to reconstruct either a whole mitogenome or a partial mitogenome," said the paper's first author Niall O'Sullivan, a PhD student at University College Dublin based at the Institute for Mummies and the Iceman in Bolzano, Italy. "We were very happy with that." While being able to crack a 25-year-old puzzle was a momentous occasion in and of itself, the one of two implications that this discovery suggests is equally important. On one hand, the findings suggests that Copper Age people carefully chose between different wild and domesticated animals when looking for materials to make their clothes. For example, cow leather, which was found in Otzi's shoes, was the sturdiest material on his body, suggesting his boots were made for walking. Sheep leather, which made up parts of his striped coat, would have kept him warmer than other materials. On the other hand, the presence of multiple types of leather could also suggest that choosing articles of clothing was approached haphazardly, with icemen simply picking what they had readily available. Regardless of the outcome, however, it will only serve to clarify what researchers already knew. "It clarifies what we already knew — that the Iceman was an agropastoralist; that the majority [of] the food and resources that he used were of domestic origin." Of course, that "majority" component is important, as it's possible that Otzi got some of his leathers — or even finished pieces of clothing — by trading with people from other regions. Unfortunately, unless researchers happen to come across another similarly well-preserved specimen, they'll never know for sure. © 2016 Tech Times, All rights reserved. Do not reproduce without permission.
News Article | August 21, 2016
It’s said that fashion is cyclical, and that the styles of past decades are inevitably revived for new generations. But for a truly original look, trendsters should dig deeper than the neon spandex tones of the 1980s or the flower child garb of the 1960s. Why not channel the tropes of an even simpler time, beyond the flapper-dressed Jazz Age and into the Copper Age, some 5,300 years ago? Introducing the newest oldest look in the book, pioneered by Ötzi, aka the Iceman, who rocked it right into his icy grave in the Ötztal Alps around 3,300 BCE. First discovered by mountaineers in 1991, Ötzi is Europe’s oldest known natural mummy, and one of the most exquisitely preserved human specimens preserved from the Copper Age. Now, his wardrobe has been reconstructed in unprecedented detail in the latest issue of Scientific Reports. The outfit: Sheepskin loincloth and goat-leather leggings, accessorized with a bear fur hat, a deerskin quiver, a grass-string backback, and some hay-stuffed shoes to round it out. Weaponry, tools, and extensive body tattoos are recommended for optimal veracity. The result: Iceman Chic, a look as timeless as Ötzi himself. Assorted accessories in Iceman’s wardrobe. Image: Institute for Mummies and the Iceman According to one of the new study’s co-authors, archeologist Ron Pinhasi of the University College, Dublin, comprehensive DNA analysis of the Iceman’s clothing reveals that he was “pretty picky” about his threads. “To me it seems pretty sophisticated in terms of the capacities to use so many different materials from different animals,” Pinhasi told the Guardian. Indeed, the new study unearthed new details about Ötzi’s fashion sense, including the first evidence that his quiver of arrows was hewn from the hides of roe deer. The mix of domestic and wild animal origins in his getup raises new questions about the creation and myriad functions of Copper Age clothing. “The Iceman’s garments and quiver are from an assemblage of at least five different species of animal,” the new study points out. “The coat alone was a combination of at least four hides and two species: goat and sheep. This result may indicate a haphazard stitching together of clothing based upon materials that were available to the Iceman, as ancient rudimentary leather is posited to rapidly deteriorate after manufacture.” “However, the leggings were composed of goat leather, which was also used in the manufacture of a 4,500-year-old leggings from Schnidejoch, Switzerland,” the authors continue. “This result lends support to the idea that Copper Age individuals in the Alpine region selected species for specific attributes when manufacturing clothing. This may also indicate a functional choice of material based on flexibility or insulating potential.” In other words, it’s unclear whether the Iceman was more of an improvisational fashionista who worked with whatever he could find, or if there was some grander significance behind his preference for blended materials—be it functional, aesthetic, or even religious. One thing’s for certain though: This was literally a killer look. After Ötzi’s frozen body was exhumed from its alpine grave, scientists found evidence that he had been shot deep with an arrow, wounded in recent hand-to-hand combat, and beaten over the head. It seems the Iceman met with a violent and mysterious end. But damn if he didn’t go out with style.