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Articles by Andreas Kappler
Survival of cyanobacteria and mitigation of Fe(II) toxicity effects in a silica-rich Archean ocean - Nature Communications
Abstract Banded iron formations (BIF) were deposited abundantly between 2.7-2.4 Ga from iron- and silica-rich oceans, with cyanobacterial oxygen (O2) as a possible oxidant for Fe(II)(aq) oxidation and Fe(III) oxyhydroxide precipitation. However, toxic reactive oxygen species (ROS) from Fe(II)/O2 interactions might have inhibited cyanobacterial growth, contributing to the delay between cyanobacterial evolution (>3.0 Ga) and the Great Oxidation Event (2.5 Ga).
Deciphering the origin of electron exchange capacities in floodplain sediments - Communications Earth & Environment
Abstract Floodplain sediments play a central role in redox-driven biogeochemical cycles through their electron exchange capacity, yet its origin remains unclear because of strong chemical heterogeneity. Here we quantified the electron-accepting and electron-donating capacities of 45 sediments from two Yangtze River floodplains using mediated electrochemical analysis.
Isolation of ‘Candidatus Ferrigenium straubiae’ - a microaerophilic Fe(II)-oxidizing bacterium and nitrate-reducing Fe(II)-oxidizer within the community of culture KS | Microbiology Society
Volume 75, Issue 11 Article metrics loading... /content/journal/ijsem/10.1099/ijsem.0.006949 Metrics Download as PowerPoint /deliver/fulltext/ijsem/75/11/ijsem006949.html?itemId=/content/journal/ijsem/10.1099/ijsem.0.006949&mimeType=html&fmt=ahah References Hanert HH et al. The Genus Gallionella. In Dworkin M, Falkow S, Rosenberg E.
Biogeochemistry of an Iron‐ and Manganese‐Rich Stratified Lake: Tasik Biru, Malaysia, as a Modern Model Habitat for the Ancient Ocean
1 Introduction Life and Earth have coevolved over 4.5 billion years (Ga), resulting in different periods of Earth's history marked by progressive oxygenation of the atmosphere and the ocean. In the Archean eon (2.4–4 Ga), Earth was devoid of free oxygen (O2), and the ancient ocean was thought to be anoxic and rich in dissolved iron (Fe) and manganese (Mn). The rise of O2 and mild oxygenation of the surface water led to a stratified ocean with an anoxic, Fe-rich (ferruginous) bottom water.
Quantitative Enhancement of Arsenate Immobilization Induced by Vacancy Defects on Various Exposed Lattice Facets of Hematite
Quantitative Enhancement of Arsenate Immobilization Induced by Vacancy Defects on Various Exposed Lattice Facets of Hematite | Environmental Science & Technology
Climate induced microbiome alterations increase cadmium bioavailability in agricultural soils with pH below 7 - Communications Earth & Environment
Abstract Climate change and metals independently stress soil microbiomes, but their combined effects remain unresolved. Here we show that future climate affects soil cadmium through altered soil microbiome and nutrient cycles, with soil pH as critical factor. In soils with pH<7 and during summer temperatures, future climate increased porewater cadmium, shifting total and potentially active taxonomic microbiome structures.
Iron transformation mediates phosphate retention across a permafrost thaw gradient - Communications Earth & Environment
Abstract Phosphorus limits primary productivity in many (Sub-)Arctic ecosystems and may constrain biological carbon sequestration. Iron (III) oxides strongly bind phosphate in soils but can dissolve under flooded, reducing conditions induced by permafrost thaw and ground collapse. The ability for iron to regulate phosphate storage and solubility in thawing permafrost landscapes remains unclear.
Acidophilic sulphate‐reducing bacteria: Diversity, ecophysiology, and applications
INTRODUCTION Acidophilic sulphate-reducing bacteria (aSRB) belong to a very specific prokaryotic group that performs dissimilatory sulphate reduction (DSR) in acidic environments (pH < 5.0), thus contributing to sulphur cycling under these extreme conditions (Baker & Banfield, 2003; Johnson & Hallberg, 2003; Meier et al., 2004). Mining pit lakes, acid rock drainages, acid mine drainages (AMD), and acidic thermal environments are some examples of low pH habitats in which aSRB have been reported.
Inhibition of phototrophic iron oxidation by nitric oxide in ferruginous environments - Nature Geoscience
Abstract Anoxygenic phototrophic Fe(II) oxidizers (photoferrotrophs) are thought to have thrived in Earth’s ancient ferruginous oceans and played a primary role in the precipitation of Archaean and Palaeoproterozoic (3.8–1.85-billion-year-old) banded iron formations (BIFs). The end of BIF deposition by photoferrotrophs has been interpreted as the result of a deepening of water-column oxygenation below the photic zone, concomitant with the proliferation of cyanobacteria.
Environmental versus litter traits as drivers of microbial decomposer functions
Abstract Plant litter decomposition is a key ecosystem process with significant implications for global carbon cycling, soil fertility and plant productivity. Given that microbial decomposers are the main players in the decomposition process, it is surprising how little is known about their functional diversity in different habitats or their ability to respond to environmental changes.
Hydrothermal sulfidation of biogenic magnetite produces framboid-like pyrite - Communications Earth & Environment
Abstract Biogenic magnetite is a potential biosignature for microbial iron cycling in hydrothermal sulfide systems, critical environments for unraveling the emergence and early evolution of life. However, the preservation potential of biogenic magnetite under hydrothermal conditions is poorly understood. Here, we show that the hydrothermal sulfidation of abiogenic and biogenic magnetite (sulfide/iron = 4, 80 °C) yields pyrite with various distinct morphologies, including framboid-like spheroids.
Emerging investigator series: Preferential adsorption and coprecipitation of permafrost organic matter with poorly crystalline iron minerals
Emerging investigator series: Preferential adsorption and coprecipitation of permafrost organic matter with poorly crystalline iron minerals Future permafrost thaw will likely lead to substantial release of greenhouse gases due to thawing of previously unavailable organic carbon (OC). Accurate predictions of this release are limited by poor knowledge of the bioavailabity of mobilized OC during thaw.
Phototrophic Fe(II) oxidation benefits from light/dark cycles
INTRODUCTION Iron is ubiquitous in the environment and influences most other major nutrient cycles: acting as a source or sink for heavy metals, carbon, nutrients and/or toxins during mineral formation and dissolution (Eickhoff et al., 2014; Kappler et al., 2021; Mu et al., 2016; Tipping, 1981). One kind of bacteria that can facilitate Fe(II) oxidation are anoxygenic phototrophic Fe(II)-oxidizers (photoferrotrophs) like Chlorobium ferrooxidans KoFox (Heising et al., 1999; Widdel et al., 1993).
The interplay between microbial communities and soil properties - Nature Reviews Microbiology
Abstract In recent years, there has been considerable progress in determining the soil properties that influence the structure of the soil microbiome. By contrast, the effects of microorganisms on their soil habitat have received less attention with most previous studies focusing on microbial contributions to soil carbon and nitrogen dynamics.
Global Business Reports - Andreas Kappler
"A few years ago, we had to bring up Industry 4.0 topics to our clients. Now, our clients proactively discuss digitalization topics, and this is a big shift." HEAD - VERTICAL MANAGEMENT CHEMICAL & PHARMA ASEAN, SIEMENS SINGAPORE Can you present your role within Siemens, and the firm’s recent achievements in Singapore? I joined in November 2022 as Head of Vertical Management for the Chemical Industry in the ASEAN region. Our main updates are in the realms of resiliency and sustainability.
Stabilization of mineral-associated organic carbon in Pleistocene permafrost - Nature Communications
Abstract Ice-rich Pleistocene-age permafrost is particularly vulnerable to rapid thaw, which may quickly expose a large pool of sedimentary organic matter (OM) to microbial degradation and lead to emissions of climate-sensitive greenhouse gases. Protective physico-chemical mechanisms may, however, restrict microbial accessibility and reduce OM decomposition; mechanisms that may be influenced by changing environmental conditions during sediment deposition.
Fungal-Mineral Interactions Modulating Intrinsic Peroxidase-like Activity of Iron Nanoparticles: Implications for the Biogeochemical Cycles of Nutrient Elements and Attenuation of Contaminants | Environmental Science & Technology
Fungal-mediated extracellular reactive oxygen species (ROS) are essential for biogeochemical cycles of carbon, nitrogen, and contaminants in terrestrial environments. These ROS levels may be modulated by iron nanoparticles that possess intrinsic peroxidase (POD)-like activity (nanozymes). However, it remains largely undescribed how fungi modulate the POD-like activity of the iron nanoparticles with various crystallinities and crystal facets.
Meta-omics reveal Gallionellaceae and Rhodanobacter as interdependent key players for Fe(II) oxidation and nitrate reduction in the autotrophic enrichment culture KS
Geomicrobiology Yu-Ming Huang, Daniel Straub, Nia Blackwell, Andreas Kappler, Sara Kleindienst DOI: 10.1128/AEM.00496-21 ABSTRACT Nitrate reduction coupled to iron(II) oxidation (NRFO) has been recognized as an environmentally important microbial process in many freshwater ecosystems.
Potentially bioavailable iron produced through benthic cycling in glaciated Arctic fjords of Svalbard
Abstract The Arctic has the highest warming rates on Earth. Glaciated fjord ecosystems, which are hotspots of carbon cycling and burial, are extremely sensitive to this warming. Glaciers are important for the transport of iron from land to sea and supply this essential nutrient to phytoplankton in high-latitude marine ecosystems. However, up to 95% of the glacially-sourced iron settles to sediments close to the glacial source.
An evolving view on biogeochemical cycling of iron
Abstract Biogeochemical cycling of iron is crucial to many environmental processes, such as ocean productivity, carbon storage, greenhouse gas emissions and the fate of nutrients, toxic metals and metalloids. Knowledge of the underlying processes involved in iron cycling has accelerated in recent years along with appreciation of the complex network of biotic and abiotic reactions dictating the speciation, mobility and reactivity of iron in the environment.
Coupled anaerobic methane oxidation and reductive arsenic mobilization in wetland soils
Abstract Anaerobic methane oxidation is coupled to the reduction of electron acceptors, such as sulfate, and contributes to their biogeochemical cycling in the environment. However, whether arsenate acts as an alternative electron acceptor of anaerobic methane oxidation and how this influences global arsenic transformations remains elusive. Here, we present incubations of arsenate-contaminated wetland soils from seven provinces in China.
Arsenic mobilization by anaerobic iron-dependent methane oxidation
Abstract Arsenic groundwater contamination threatens the health of millions of people worldwide, particularly in South and Southeast Asia. In most cases, the release of arsenic from sediment was caused by microbial reductive dissolution of arsenic-bearing iron(III) minerals with organic carbon being used as microbial electron donor. Although in many arsenic-contaminated aquifers high concentrations of methane were observed, its role in arsenic mobilization is unknown.
Fungal Nanophase Particles Catalyze Iron Transformation for Oxidative Stress Removal and Iron Acquisition
Highlights • Biogenic ferrihydrite nanoparticles were formed during fungus-hematite interactions • Biogenic ferrihydrite nanoparticles can perform as catalysts that imitate peroxidase • Non-lattice oxygen in the nanomaterials was responsible for the catalytic activity Summary Microbe-mineral interactions have shaped the surface of the Earth and impacted the evolution of plants and animals.
Role of Iron Sulfide Phases in the Stability of Noncrystalline Tetravalent Uranium in Sediments
Download Hi-Res ImageDownload to MS-PowerPointCite This:Environ. Sci. Technol. 2020, XXXX, XXX Learn More about expanded access to ACS Publications research. RETURN TO ARTICLES ASAPPREVArticleNEXT Luca Loreggian Julian Sorwat Julian Sorwat Center for Applied Geoscience (ZAG), Eberhard Karls Universitaet Tuebingen, Sigwartstrasse 10, Tuebingen 72076, Germany James M.
Influence of Physical Perturbation on Fe(II) Supply in Coastal Marine Sediments
Iron (Fe) biogeochemistry in marine sediments is driven by redox transformations creating Fe(II) and Fe(III) gradients. As sediments are physically mixed by wave action or bioturbation, Fe gradients re-establish regularly. In order to identify the response of dissolved Fe(II) (Fe2+) and Fe mineral phases toward mixing processes, we performed voltammetric microsensor measurements, sequential Fe extractions, and Mössbauer spectroscopy of 12 h light–dark cycle incubated marine coastal sediment.
Fe(III) Photoreduction Producing Feaq2+ in Oxic Freshwater Sediment
Download Hi-Res ImageDownload to MS-PowerPointCite This:Environ. Sci. Technol.
FeII oxidation by molecular O2 during HCl extraction
RESEARCH ARTICLE Previous Next Contents Vol 8(2) Katharina Porsch A B and Andreas Kappler A C + Author Affiliations - Author Affiliations A Geomicrobiology, Center for Applied Geosciences, University of Tuebingen, Sigwartstrasse 10, D-72076 Tuebingen, Germany. B Present address: Helmholtz Centre for Environmental Research – UFZ, Department of Bioenergy, Permoserstrasse 15, D-04318 Leipzig, Germany. C Corresponding author.
Iron Lung: How Rice Roots Induce Iron Redox Changes in the Rhizosphere and Create Niches for Microaerophilic Fe(II)-Oxidizing Bacteria
Paddy soils represent more than 6% of the world’s cultivated and arable land surface.
Cryptic Cycling of Complexes Containing Fe(III) and Organic Matter by Phototrophic Fe(II)-Oxidizing Bacteria
Geomicrobiology Chao Peng, Casey Bryce, Anneli Sundman, Andreas Kappler Isaac Cann, Editor DOI: 10.1128/AEM.02826-18 ABSTRACT Fe-organic matter (Fe-OM) complexes are abundant in the environment and, due to their mobility, reactivity, and bioavailability, play a significant role in the biogeochemical Fe cycle.
Trace Element Concentrations in Firewood and Corresponding Stove Ashes
Julian Tejada*†‡ , Peter Grammer†, Andreas Kappler‡ , and Harald Thorwarth*† † University of Applied Forest Sciences Rottenburg, Schadenweilerhof, D-72108 Rottenburg am Neckar, Germany ‡ Geomicrobiology, Center for Applied Geosciences, University of Tuebingen, Sigwartstrasse 10, D-72076 Tuebingen, Germany Energy Fuels, Article ASAP DOI: 10.1021/acs.energyfuels.8b03732 Publication Date (Web): February 12, 2019 Copyright © 2019 American Chemical Society *E-mail: tejada@hs-rottenburg.de.,...
Cryptic cycling of Fe(III)-organic matter complexes by phototrophic Fe(II)-oxidizing bacteria
Geomicrobiology Chao Peng, Casey Bryce, Anneli Sundman, Andreas Kappler DOI: 10.1128/AEM.02826-18 ABSTRACT Fe-organic matter (Fe-OM) complexes are abundant in the environment and, due to their mobility, reactivity and bioavailability, play a significant role in the biogeochemical Fe cycle.
Impact of Organic Matter on Iron(II)-Catalyzed Mineral Transformations in Ferrihydrite-Organic Matter Coprecipitates
Poorly crystalline Fe(III) (oxyhydr)oxides like ferrihydrite are abundant in soils and sediments and are often associated with organic matter (OM) in the form of mineral-organic aggregates. Under anoxic conditions, interactions between aqueous Fe(II) and ferrihydrite lead to the formation of crystalline secondary minerals, like lepidocrocite, goethite, or magnetite.
Pyrite formation from FeS and H2S is mediated by a novel type of microbial energy metabolism
Pyrite formation from FeS and H2S is mediated by a novel type of microbial energy metabolism Joana Thiel, James Byrne, Andreas Kappler, Bernhard Schink, Michael Pester bioRxiv 396978; doi: https://doi.org/10.1101/396978
Size dependent microbial oxidation and reduction of magnetite nano- and micro-particles
Two types of magnetite were synthesized for these experiments, denoted Nanomag and Micromag in reference to their respective sizes, i.e. Nanomag corresponds to magnetite nanoparticles and Micromag corresponds to magnetite microparticles. Magnetic susceptibility (MS) measurements enable direct measurements of the magnetic changes to the microbe-magnetite cultures in situ without removing any sample (Fig. 1).
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