A5007885976- Microbial bioremediation and biosurfactants
- Microbial Community Ecology and Physiology
- Mass Spectrometry Techniques and Applications
- Methane Hydrates and Related Phenomena
- Microbial Metabolic Engineering and Bioproduction
- Geology and Paleoclimatology Research
- Surfactants and Colloidal Systems
- Environmental DNA in Biodiversity Studies
- Petroleum Processing and Analysis
- Isotope Analysis in Ecology
- Environmental Chemistry and Analysis
- Enzyme Production and Characterization
- Bacterial Genetics and Biotechnology
- Spectroscopy Techniques in Biomedical and Chemical Research
- Atmospheric and Environmental Gas Dynamics
- Toxic Organic Pollutants Impact
- Climate change and permafrost
- Genomics and Phylogenetic Studies
- Hydrocarbon exploration and reservoir analysis
- Biosensors and Analytical Detection
- CO2 Sequestration and Geologic Interactions
- Polar Research and Ecology
- Bacterial biofilms and quorum sensing
- Geochemistry and Elemental Analysis
- Pesticide Exposure and Toxicity
Freie Universität Berlin
2022-2024
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung
2020-2024
GFZ Helmholtz Centre for Geosciences
2016-2020
European Space Research and Technology Centre
2011-2014
University of Ulster
2005-2013
Università degli Studi della Tuscia
2005
Abstract Oil spills from pipeline ruptures are a major source of terrestrial petroleum pollution in cold regions. However, our knowledge the bacterial response to crude oil contamination regions remains be further expanded, especially terms community shifts and potential development hydrocarbon degraders. In this study we investigated changes microbial diversity, population size keystone taxa permafrost soils at four different sites along China-Russia prior after perturbation with oil. We...
The self-assembly in solution and adsorption at the air−water interface, measured by small-angle neutron scattering, SANS, reflectivity, NR, of monorhamnose dirhamnose rhamnolipids (R1, R2) their mixtures, are discussed. production deuterium-labeled (required for NR studies) from a Pseudomonas aeruginosa culture separation into pure R1 R2 components is described. At exhibit Langmuir-like isotherms, with saturated area/molecule values about 60 75 Å2, respectively. In R1/R2 there strong...
Abstract Pronounced glacial and interglacial climate cycles characterized northern ecosystems during the Pleistocene. Our understanding of resultant community transformations past ecological interactions strongly depends on taxa found in fossil assemblages. Here, we present a shotgun metagenomic analysis sedimentary ancient DNA ( seda DNA) to infer ecosystem‐wide biotic composition (from viruses megaherbivores) from Middle Late Pleistocene at Batagay megaslump, East Siberia. The records...
The use of small angle neutron scattering, SANS, reflectivity, NR, and surface tension to study the mixing properties biosurfactant rhamnolipid with a conventional anionic surfactant, sodium dodecyl 6-benzene sulfonate, LAS, is reported. monorhamnose rhamnolipid, R1, mixes close ideally LAS at air−water interface, whereas for mixtures dirhamnose R2, strongly partitions interface relative probably because steric hindrance larger R2 headgroup. These trends in binary are also reflected ternary...
The self-assembly in aqueous solution of the acidic (AS) and lactonic (LS) forms sophorolipid biosurfactant, their mixtures, mixtures with anionic surfactant sodium dodecyl benzene sulfonate, LAS, has been studied using predominantly small-angle neutron scattering, SANS, at relatively low concentrations <30 mM. more hydrophobic small unilamellar vesicles concentrations, concentration range 0.2 to 3 mM, transforms via a larger vesicle structure 7 mM disordered dilute phase tubules higher 10...
Soil microcosms have been used to demonstrate the ability of indigenous soil thermophiles degrade effectively a representative alkane (n-hexadecane). A fragment mono-oxygenase gene (alkB) was amplified from thermophilic Geobacillus thermoleovorans strain T70 by PCR using degenerate primers. The amplicon demonstrated 96% sequence similarity with alkB Rhodococcus erythropolis. Critical controls ensured that positive signal detected not result mesophilic organisms. reverse transcription...
The adsorption of the lactonic (LS) and acidic (AS) forms sophorolipid their mixtures with anionic surfactant sodium dodecyl benzene sulfonate (LAS) has been measured at air/water interface by neutron reflectivity, NR. AS LS sophorolipids adsorb Langmuir-like isotherms. more hydrophobic is surface active than AS, a lower critical micellar concentration, CMC, stronger adsorption, an area/molecule ∼70 Å(2) compared 85 for AS. shows maximum in its CMC which appears to be associated mixture...
The impact of Ca2+ counterions on the adsorption at air–water interface and self-assembly in aqueous solution rhamnolipid biosurfactant its mixture with anionic surfactant sodium dodecylbenzenesulfonate, LAS, has been studied using neutron reflectometry small-angle scattering. results illustrate how rhamnolipids are calcium tolerant their blending conventional surfactants improves tolerance surfactant. relatively little effect upon monorhamnose, R1, dirhamnose, R2, rhamnolipids, even high...
Following a screening of Antarctic glacier forefield-bacteria for novel cold-active enzymes, psychrophilic strain Psychrobacter sp. 94-6PB was selected further characterization enzymatic activities. The produced lipases and proteases in the temperature range 4-18°C. coding sequence an extracellular serine-protease then identified via comparative analysis across genomes, PCR-amplified our expressed heterologous host E. coli. purified enzyme (80 kDa) resulted to be alkaline protease,...
Aerosols from dust storms generated in the Sahara-Sahel desert area of Africa are transported north over Europe and periodically result dry precipitation Mediterranean region. Samples collected Turkey Greece following two distinct storm events contained viable thermophilic organisms genus Geobacillus, namely G. thermoglucosidasius thermodenitrificans, recently reclassified Aeribacillus pallidus (formerly Geobacillus pallidus). We present here evidence that African create an atmospheric...
We have applied an image-based approach combining epifluorescence microscopy, electron microscopy and nanoscale secondary ion mass spectrometry (nanoSIMS) with stable isotope probing to examine directly the characteristic cellular features involved in expression of cold phenotype Antarctic bacterium Clostridium psychrophilum exposed a temperature range from +5 −15 °C under anoxic conditions. observed dramatic morphological changes depending on temperature. At temperatures below −10 °C, cell...
Abstract The study of environmental ancient DNA provides us with the unique opportunity to link ecosystem change over a millennial timescale. Paleorecords such as lake sediments contain genetic pools past living organisms that are valuable source information reconstruct how ecosystems were and they changed in response climate past. Here, we report on paleometagenomics sedimentary record northern Siberia covering 6700 years. We integrated taxonomic functional gene analysis, which enabled shed...
Abstract This study utilizes nanoscale Fourier transform infrared spectroscopy (nanoFTIR) to perform stable isotope probing (SIP) on individual bacteria cells cultured in the presence of 13 C-labelled glucose. SIP-nanoFTIR simultaneously quantifies single-cell metabolism through and acquires cellular morphological information via atomic force microscopy. The redshift amide I peak corresponds isotopic enrichment newly synthesized proteins. These observations translational activity are...
This study utilizes nanoscale Fourier transform infrared spectroscopy (nanoFTIR) to perform stable isotope probing (SIP) on individual bacteria cells cultured in the presence of