A5077576829- Methane Hydrates and Related Phenomena
- Geology and Paleoclimatology Research
- Microbial Community Ecology and Physiology
- Isotope Analysis in Ecology
- Hydrocarbon exploration and reservoir analysis
- Marine and coastal ecosystems
- Geological Studies and Exploration
- Genomics and Phylogenetic Studies
- Photosynthetic Processes and Mechanisms
- Geochemistry and Geologic Mapping
- Protein Structure and Dynamics
- Lipid Membrane Structure and Behavior
- Paleontology and Stratigraphy of Fossils
- Metabolomics and Mass Spectrometry Studies
- Atmospheric and Environmental Gas Dynamics
- Geological formations and processes
- Geological and Geochemical Analysis
- Marine and environmental studies
- Protist diversity and phylogeny
- Porphyrin Metabolism and Disorders
- Groundwater and Isotope Geochemistry
- Marine Bivalve and Aquaculture Studies
- Fluoride Effects and Removal
- Enterobacteriaceae and Cronobacter Research
- Ocean Acidification Effects and Responses
Harvard University
2018-2025
Kiel University
2021-2025
Planetary Science Institute
2018-2025
University of Bremen
2014-2024
Hong Kong Metropolitan University
2023
Leibniz Association
2023
Harvard University Press
2019-2021
Summary Thaumarchaeota are globally distributed and abundant microorganisms occurring in diverse habitats thus represent a major source of archaeal lipids. The scope lipids as taxonomic markers microbial ecological studies is limited by the scarcity comparative data on membrane lipid composition cultivated representatives, including phylum . Here, we comprehensively describe core intact polar (IPL) inventory ten ammonia‐oxidising thaumarchaeal cultures representing all four characterized...
Significance The membrane lipids of marine Archaea form the basis temperature proxy called TEX 86 , which is used for paleoclimate reconstructions from Jurassic to present. To date there remains no satisfactory explanation how planktonic are able record water column temperatures, because does not correlate well with in situ growth temperatures modern ocean. Here we show that lipid ratio changes response cellular rate, controlled by ammonia oxidation rate. This implies variation depth...
A new clade of archaea has recently been proposed to constitute the seventh methanogenic order, Methanomassiliicoccales, which is related Thermoplasmatales and uncultivated archaeal clades deep-sea hydrothermal vent Euryarchaeota group 2 marine II but only distantly other methanogens. In this study, we investigated membrane lipid composition Methanomassiliicoccus luminyensis, sole cultured representative order. The inventory M. luminyensis comprises a unique assemblage novel lipids as well...
The distribution of respiratory quinone electron carriers among cultivated organisms provides clues on both the taxonomy their producers and redox processes these are mediating. Our study inventories 25 archaeal species belonging to phyla Eury-, Cren- Thaumarchaeota facilitates use as chemotaxonomic markers for ecologically important clades. Saturated monounsaturated menaquinones with six isoprenoid units forming alkyl chain may serve Thaumarchaeota. Other diagnostic biomarkers...
Ectoine and hydroxyectoine are compatible solutes widely synthesized by members of the Bacteria to cope with high osmolarity surroundings. Inspection 557 archaeal genomes revealed that only 12 strains affiliated Nitrosopumilus, Methanothrix or Methanobacterium genera harbour ectoine/hydroxyectoine gene clusters. Phylogenetic considerations suggest these Archaea have acquired genes through horizontal transfer events. Using Thaumarchaeon 'Candidatus Nitrosopumilus maritimus' as an example, we...
Summary Membrane lipids of marine planktonic archaea have provided unique insights into archaeal ecology and paleoceanography. However, past studies in suspended particulate matter (SPM) sediments mainly focused on a small class fully saturated glycerol dibiphytanyl tetraether (GDGT) homologues identified decades ago. The apparent low structural diversity GDGTs is strong contrast to the high metabolism taxonomy among archaea. Furthermore, adaptation deep ocean remains poorly constrained. We...
Abstract Hopanoid lipids, bacteriohopanols and bacteriohopanepolyols, are membrane components exclusive to bacteria. Together with their diagenetic derivatives, they commonly used as biomarkers for specific bacterial groups or biogeochemical processes in the geologic record. However, sources of hopanoids marine freshwater environments remain inadequately constrained. Recent marker gene studies suggest a widespread potential hopanoid biosynthesis bacterioplankton, including nitrifying (i.e.,...
Abstract The Paleocene‐Eocene Thermal Maximum (PETM) was a transient global warming event and is recognized in the geologic record by prolonged negative carbon isotope excursion (CIE). onset of CIE due to rapid influx 13 C‐depleted into ocean‐atmosphere system. However, mechanisms required sustain remains unclear. Enhanced mobilization oxidation petrogenic organic (OC petro ) has been invoked explain elevated atmospheric dioxide concentrations after CIE. existing evidence limited...
Abstract The TEX 86 proxy, based on the distribution of isoprenoid glycerol dialkyl tetraethers (iGDGTs) from planktonic Thaumarchaeota, is widely used to reconstruct sea surface temperature (SST). Recent observations species‐specific and regionally dependent ‐SST relationships in cultures modern ocean raise question whether nonthermal factors may have impacted paleorecords. Here we evaluate effects ecological changes using one Pliocene two Pleistocene sapropels Mediterranean Sea. We find...
Abstract Sediment-hosted CO2-rich aquifers deep below the Colorado Plateau (USA) contain a remarkable diversity of uncultivated microorganisms, including Candidate Phyla Radiation (CPR) bacteria that are putative symbionts unable to synthesize membrane lipids. The origin organic carbon in these ecosystems is unknown and source CPR lipids remains elusive. We collected cells from groundwater brought surface by eruptions Crystal Geyser, sequenced community, analyzed whole community lipidome...
Abstract. A growing body of observations reveals rapid changes in both the total inventory and distribution marine oxygen over later half 21st century, leading to increased interest extending oxygenation records into past. Use paleo-oxygen proxies have potential extend spatial temporal range current records, bound pre-anthropogenic baselines, provide datasets necessary test climate models under different boundary conditions, ultimately understand how ocean responds beyond decadal scale...
Abstract A negative carbon isotope excursion recorded in terrestrial and marine archives reflects massive emissions into the exogenic reservoir during Paleocene-Eocene Thermal Maximum. Yet, discrepancies estimates from different sample types lead to substantial uncertainties source, scale, timing of emissions. Here we show that membrane lipids planktonic archaea reliably record both surface ocean warming Novel records isotopic composition crenarchaeol constrain global magnitude −4.0 ± 0.4‰,...
Abstract. A growing body of observations has revealed rapid changes in both the total inventory and distribution marine oxygen over latter half 20th century, leading to increased interest extending oxygenation records into past. The use paleo-oxygen proxies potential extend spatial temporal range current records, constrain pre-anthropogenic baselines, provide datasets necessary test climate models under different boundary conditions, ultimately understand how ocean responds beyond...
The dominant organisms in modern oxic ecosystems rely on respiratory quinones with high redox potential (HPQs) for electron transport aerobic respiration and photosynthesis. diversification of quinones, from low (LPQ) anaerobes to HPQs aerobes, is assumed have followed Earth's surface oxygenation ~2.3 billion years ago. However, the evolutionary origins remain unresolved. Here, we characterize structure biosynthetic pathway an ancestral HPQ, methyl-plastoquinone (mPQ), that unique bacteria...
Over the last 50 years, permanently anoxic regions in ocean have quadrupled size due to deoxygenation derived from global warming and climate change. Marine basins are characterized by strong vertical redox variability. In deep, waters of these basins, bulk measurements showed an increase concentration some dissolved organic matter (DOM) components such as carbon (DOC) sulfur (DOS). However, direct abiotic effect oxygen variability into DOM composition remains unclear. this study, we...
ABSTRACT The stable hydrogen isotope composition (δ 2 H) of lipid biomarkers can track environmental processes and remain over geologically relevant time scales, enabling studies past climate, hydrology, ecology. Most research has focused on lipids from the domain Eukarya (e.g., plant waxes, long-chain alkanes), potential prokaryotic Archaea to offer unique insights into environments not captured by eukaryotic remains unclear. Here, we investigate H-isotope biphytanes in Sulfolobus...
Abstract. Marine glycerol dialkyl tetraethers (GDGTs) are used in various proxies (such as TEX86) to reconstruct past ocean temperatures. Over 20 years of improvements GDGT sample processing, analytical techniques, data interpretation and our understanding proxy functioning have led the collective development a set best practices all these areas. Further, importance Open Science research has increased emphasis on systematic documentation generation, reporting archiving processes for optimal...
Summary Heterotrophic P roteobacteria and A ctinobacteria were isolated from L ake M atano, I ndonesia, a stratified, ferruginous (iron‐rich), ultra‐oligotrophic lake with phosphate concentrations below 50 nM. Here, we describe the growth of eight strains heterotrophic bacteria on variety soluble insoluble sources phosphorus. When transferred to medium without added phosphorus ( ), isolates grow slowly, their RNA content falls as low 1% cellular dry weight, 86–100% membrane lipids are...