Search results for "Earth"

2020

ABSTRACT The vertical structuring of methanotrophic communities and its genetic controllers remain understudied in the water columns of oxygen-stratified lakes. Therefore, we used 16S rRNA gene sequencing to study the vertical stratification patterns of methanotrophs in two boreal lakes, Lake Kuivajärvi and Lake Lovojärvi. Furthermore, metagenomic analyses were performed to assess the genomic characteristics of methanotrophs in Lovojärvi and the previously studied Lake Alinen Mustajärvi. The methanotroph communities were vertically structured along the oxygen gradient. Alphaproteobacterial methanotrophs preferred oxic water layers, while Methylococcales methanotrophs, consisting of putative…

Biological and physical modification of carbonate system parameters along the salinity gradient in shallow hypersaline solar salterns in Trapani, Ita…

2017

Abstract We investigated changes in the chemical characteristics of evaporating seawater under the influence of microbial activity by conducting geochemical analyses of the brines and evaporite sediments collected from solar salterns in Trapani, Italy. The microbial activity had a substantial effect on the carbonate system parameters. Dissolved inorganic carbon (DIC) was substantially removed from the brine during the course of evaporation from the seawater to the point where calcium carbonate precipitates, with an accompanying decrease in its carbon isotopic composition (δ 13 C DIC ) to as low as −10.6‰. Although the removal of DIC was due to calcium carbonate precipitation, photosynthesis…

'Palaeoshellomics' reveals the use of freshwater mother-of-pearl in prehistory

2019

The extensive use of mollusc shell as a versatile raw material is testament to its importance in prehistoric times. The consistent choice of certain species for different purposes, including the making of ornaments, is a direct representation of how humans viewed and exploited their environment. The necessary taxonomic information, however, is often impossible to obtain from objects that are small, heavily worked or degraded. Here we propose a novel biogeochemical approach to track the biological origin of prehistoric mollusc shell. We conducted an in-depth study of archaeological ornaments using microstructural, geochemical and biomolecular analyses, including ‘palaeoshellomics’, the first…

Comments on "Dental lessons from past to present: Ultrastructure and composition of teeth from plesiosaurs, dinosaurs, extinct and recent sharks" by …

2016

The paper mentioned in the title suggests that several groups of extinct vertebrates used fluoroapatite as a tooth mineral in dentine and enamel when alive; its authors posit that this tooth mineralization drastically changed in all these lineages at some point during their evolution, leading to the use of hydroxyapatite as an alternative primary tooth mineral, because of hitherto unconsidered environmental changes. These conclusions are based on their finding high fluoride levels (i.e. fluoroapatite) in the dentine of fossilised shark teeth as well as in both the dentine and enamel of plesiosaurs, mosasaurs, and dinosaurs, which is in sharp contrast to recent teeth (which contain almost no…

Ancient cattle genomics, origins, and rapid turnover in the Fertile Crescent

2019

Cattle were domesticated ∼10,000 years ago, but analysis of modern breeds has not elucidated their origins. Verdugo et al. performed genome-wide analysis of 67 ancient Near Eastern Bos taurus DNA samples. Several populations of ancient aurochs were progenitors of domestic cows. These genetic lineages mixed ∼4000 years ago in a region around the Indus Valley. Interestingly, mitochondrial analysis indicated that genetic material likely derived from arid-adapted Bos indicus (zebu) bulls was introduced by introgression.Science, this issue p. 173Genome-wide analysis of 67 ancient Near Eastern cattle, Bos taurus, remains reveals regional variation that has since been obscured by admixture in mode…

The Use of Wild Plants in the Palaeolithic and Neolithic of Northwestern Africa: Preliminary Results from the PALEOPLANT Project

2018

Carrión Marco Y., Morales J., Portillo M., Pérez-Jordà G., Peña-Chocarro L., Zapata L. (2018) The Use of Wild Plants in the Palaeolithic and Neolithic of Northwestern Africa: Preliminary Results from the PALEOPLANT Project. En: Mercuri A., D'Andrea A., Fornaciari R., Höhn A. (eds.) Plants and People in the African Past. Springer, Cham

BIOAEROSOL

2017

Cultural heritage constitutive materials can provide excellent substrates for microbial colonisation, highly influenced by thermo-hygrometric parameters. In cultural heritage-related environments, a detrimental microbial load may be present both on manufact surface and in the aerosol. Confined environments (museums, archives, deposits, caves, hypogea) have peculiar structures and dif- ferent thermo-hygrometric parameters, influencing the development of a wide range of microbial species, able to induce artefact biodeterioration and to release biological particles in the aerosol (spores, cellular debrides, toxins, allergens) potentially dangerous for the human health (visitors/users). In orde…

Reconstruction of Past Dynamics of Methane-Oxidizing Bacteria in Lake Sediments Using a Quantitative PCR Method: Connecting Past Environmental Change…

2019

AbstractIn this study, a quantitative PCR (qPCR) method was applied to amplify ancient DNA (aDNA) of different methane-oxidizing bacteria (MOB) types in lake sediments and to reconstruct microbial community dynamics over the last 1200 years. We also used reconstructions of in-lake nutrients concentrations, air temperature fluctuations, and sedimentary organic matter dynamics to study impacts of past environmental and climatic changes on MOB community composition. DNA preservation in lake sediments is sufficient, and qPCR amplification was successfully applied to the analysis of MOB aDNA. Temporal changes in MOB community showed different patterns between lakes, and drivers of past MOB dynam…

Oil-degrading bacteria from a membrane bioreactor (BF-MBR) system for treatment of saline oily waste: Isolation, identification and characterization …

2016

A collection of forty-two (42) strains was obtained during microbiological screening of a Membrane Bioreactor (MBR) system developed for the treatment of saline oily waste originated from marine transportation. The diversity of the bacterial collection was analyzed by amplification and sequencing of the 16S rRNA gene. Taxonomic analysis showed high level of identity with recognized sequences of seven (7) distinct bacterial genera (Alcanivorax, Erythrobacter, Marinobacter, Microbacterium, Muricauda, Rhodococcus and Rheinheimera). The biotechnological potential of the isolates was screened considering an important factor such as the biosurfactant production. In particular fourteen (14) biosur…

Eawag-Soil in enviPath: a new resource for exploring regulatory pesticide soil biodegradation pathways and half-life data.

2017

Developing models for the prediction of microbial biotransformation pathways and half-lives of trace organic contaminants in different environments requires as training data easily accessible and sufficiently large collections of respective biotransformation data that are annotated with metadata on study conditions. Here, we present the Eawag-Soil package, a public database that has been developed to contain all freely accessible regulatory data on pesticide degradation in laboratory soil simulation studies for pesticides registered in the EU (282 degradation pathways, 1535 reactions, 1619 compounds and 4716 biotransformation half-life values with corresponding metadata on study conditions)…