A5048867125- Microbial Community Ecology and Physiology
- Wastewater Treatment and Nitrogen Removal
- Microbial Fuel Cells and Bioremediation
- Protist diversity and phylogeny
- Marine and coastal ecosystems
- Marine Sponges and Natural Products
- Water Treatment and Disinfection
- Polar Research and Ecology
- Synthetic Organic Chemistry Methods
- Synthesis and Biological Activity
- Marine Biology and Environmental Chemistry
- Genomics and Phylogenetic Studies
- Methane Hydrates and Related Phenomena
- Paleontology and Stratigraphy of Fossils
- Marine Toxins and Detection Methods
- Oral microbiology and periodontitis research
- Environmental DNA in Biodiversity Studies
- Medical Imaging and Pathology Studies
- Geochemistry and Elemental Analysis
- Chemical Reactions and Isotopes
- Nuclear Physics and Applications
- Distributed systems and fault tolerance
- Isotope Analysis in Ecology
- Ammonia Synthesis and Nitrogen Reduction
- Gut microbiota and health
Max Planck Institute for Marine Microbiology
2018-2025
University of Vienna
2014-2024
Ecologie Microbienne Lyon
2023
Significance Nitrification, the sequential aerobic oxidation of ammonia via nitrite to nitrate, is a key process biogeochemical nitrogen cycle and catalyzed by two microbial guilds (nitrifiers): oxidizers nitrite-oxidizing bacteria (NOB). NOB are generally considered as metabolically restricted dependent on oxidizers. Here, we report that, surprisingly, many ecosystems ( Nitrospira ) convert urea, an important source in nature, CO 2 . Thus, supply urease-negative with receive produced...
Abstract Nitrogen (N 2 ) fixation in oligotrophic surface waters is the main source of new nitrogen to ocean 1 and has a key role fuelling biological carbon pump . Oceanic N been attributed almost exclusively cyanobacteria, even though genes encoding nitrogenase, enzyme that fixes into ammonia, are widespread among marine bacteria archaea 3–5 Little known about these non-cyanobacterial fixers, direct proof they can fix so far lacking. Here we report discovery -fixing symbiont, ‘ Candidatus...
Microorganisms are responsible for nutrient removal and resource recovery in wastewater treatment plants (WWTPs), their diversity is often studied by 16S rRNA gene amplicon sequencing. However, this approach underestimates the abundance of Patescibacteria due to low coverage commonly used PCR primers highly divergent bacterial phylum. Therefore, our current understanding global diversity, distribution, ecological role WWTPs very incomplete. This particularly relevant as considered be...
ABSTRACT Nitrification is a key process of the biogeochemical nitrogen cycle and biological wastewater treatment. The second step, nitrite oxidation to nitrate, catalyzed by phylogenetically diverse, chemolithoautotrophic nitrite-oxidizing bacteria (NOB). Uncultured NOB from genus “ Candidatus Nitrotoga” are widespread in natural engineered ecosystems. Knowledge about their biology sparse, because no genomic information pure Ca . culture was available. Here we obtained first isolate...
Abstract Nitrification, the oxidation of ammonia via nitrite to nitrate, is a key process in marine nitrogen (N) cycling. Although oceanic and are balanced, ammonia-oxidizing archaea (AOA) vastly outnumber main oxidizers, bacterial Nitrospinae. The ecophysiological reasons for this discrepancy abundance unclear. Here, we compare substrate utilization growth Nitrospinae AOA Gulf Mexico. Based on our results, more than half cellular N-demand met by organic-N compounds urea cyanate, while...
Nitrite-oxidizing bacteria of the genus Nitrospira are key players biogeochemical nitrogen cycle. However, little is known about their occurrence and survival strategies in extreme pH environments. Here, we report on discovery physiologically versatile, haloalkalitolerant that drive nitrite oxidation at exceptionally high pH. distribution, diversity, ecophysiology were studied hypo- subsaline (1.3-12.8 g salt/l), highly alkaline (pH 8.9-10.3) lakes by amplicon sequencing, metagenomics,...
Abstract Mitochondria are specialized eukaryotic organelles that have a dedicated function in oxygen respiration and energy production. They evolved about 2 billion years ago from free-living bacterial ancestor (probably an alphaproteobacterium), process known as endosymbiosis 1,2 . Many unicellular eukaryotes since adapted to life anoxic habitats their mitochondria undergone further reductive evolution 3 As result, obligate anaerobic with mitochondrial remnants derive mostly fermentation 4...
Abstract Blooms of dark pigmented microalgae accelerate glacier and ice sheet melting by reducing the surface albedo. However, role nutrient availability in regulating algal growth on remains poorly understood. Here, we investigate algae Greenland Ice Sheet, providing single-cell measurements carbon:nitrogen:phosphorus (C:N:P) ratios assimilation rates dissolved inorganic carbon (DIC), ammonium nitrate following amendments. The analyses reveal high C:N C:P atomic biomass as well...
Guanidine is a chemically stable nitrogen compound that excreted in human urine and widely used manufacturing of plastics, as flame retardant component propellants, well known protein denaturant biochemistry
Abstract Biological N 2 fixation was key to the expansion of life on early Earth. The -fixing microorganisms and nitrogenase type used in Proterozoic are unknown, although it has been proposed that canonical molybdenum-nitrogenase not due low molybdenum availability. We investigate Lake Cadagno, an analogue system sulfidic continental margins, using a combination biogeochemical, molecular single cell techniques. In purple sulfur bacteria (PSB) responsible for high rates, our knowledge...
Deep oligotrophic lakes sustain large populations of the class Nitrososphaeria (Thaumarchaeota) in their hypolimnion. They are thought to be key ammonia oxidizers this habitat, but impact on N-cycling has rarely been quantified. We followed archaeal population one Europe's largest lakes, Lake Constance, for two consecutive years using metagenomics and metatranscriptomics combined with stable isotope-based activity measurements. An abundant (8-39% picoplankton) transcriptionally active...
Ammonia-oxidizing bacteria (AOB) of the betaproteobacterial genera Nitrosomonas and Nitrosospira are key nitrifying microorganisms in many natural engineered ecosystems. Since AOB remain uncultured, fluorescence situ hybridization (FISH) with rRNA-targeted oligonucleotide probes has been one most widely used approaches to study community composition, abundance, other features directly environmental samples. However, established AOB-specific 16S FISH were designed up two decades ago, based on...
Abstract Marine sponges are critical components of marine benthic fauna assemblages, where their filter-feeding and reef-building capabilities provide bentho-pelagic coupling crucial habitat. As potentially the oldest representation a metazoan-microbe symbiosis, they also harbor dense, diverse, species-specific communities microbes, which increasingly recognized for contributions to dissolved organic matter (DOM) processing. Recent omics-based studies sponge microbiomes have proposed...
Stable isotope probing (SIP) is a key tool for identifying the microorganisms catalyzing turnover of specific substrates in environment and to quantify their relative contributions biogeochemical processes. However, SIP-based studies are subject uncertainties posed by cross-feeding, where release isotopically labeled products, which then used other microorganisms, instead incorporating added tracer directly. Here, we introduce SIP approach that has potential strongly reduce cross-feeding...
<title>Abstract</title> Blooms of dark pigmented microalgae accelerate glacier and ice sheet melting by reducing the surface albedo. However, role nutrient availability in regulating their growth remains poorly understood. We studied algae on Greenland Ice Sheet, providing first single-cell based data carbon:nitrogen:phosphorus (C:N:P) ratios assimilation dissolved inorganic carbon (DIC) DIN following various amendments. The dataset revealed high C:N C:P atomic algal biomass presence...
Abstract Ammonia-oxidizing archaea are the most abundant chemolithoautotrophs in ocean, comprising up to 40% of microbial cells deep waters, and assumed dominate dissolved inorganic carbon (DIC) fixation below sunlit surface layer. Yet, supply reduced nitrogen from particulate organic matter flux is insufficient support amount nitrification required sustain measured DIC rates dark ocean. The aim this study was quantify contribution ammonia oxidizers We used phenylacetylene - a specific...
Abstract Background Microorganisms are responsible for nutrient removal and resource recovery in wastewater treatment plants (WWTPs), their diversity is often studied by 16S rRNA gene amplicon sequencing. However, this approach underestimates the abundance of Patescibacteria due to low coverage commonly used PCR primers highly divergent bacterial phylum. Therefore, our current understanding global diversity, distribution, ecological role WWTPs very incomplete. This particularly relevant as...
Abstract Nitrification rate measurements provide critical information on the performance of an environmental process central to N cycle and are best studied using isotope labeling techniques. However, combining high sensitivity techniques with selected inhibition nitrifiers as a whole or specific nitrifier guilds has not been established in limnology. This can be achieved different concentrations commonly used nitrification inhibitor allylthiourea (ATU). In 15 N‐ammonium oxidation technique,...
Abstract Nitrite-oxidizing bacteria of the genus Nitrospira are key players biogeochemical nitrogen cycle. However, little is known about their occurrence and survival strategies in extreme pH environments. Here, we report on discovery physiologically versatile, haloalkalitolerant that drive nitrite oxidation at exceptionally high pH. distribution, diversity, ecophysiology were studied hypo- subsaline (1.3-12.8 g salt/l), highly alkaline (pH 8.9-10.3) lakes by amplicon sequencing,...
Abstract Ammonia-oxidizing bacteria (AOB) of the betaproteobacterial genera Nitrosomonas and Nitrosospira are key nitrifying microorganisms in many natural engineered ecosystems. Since AOB remain uncultured, fluorescence situ hybridization (FISH) with rRNA-targeted oligonucleotide probes has been one most widely used approaches to study community composition, abundance, other features directly environmental samples. However, established AOB-specific 16S FISH were designed up two decades ago,...