A5015324999- Geophysics and Gravity Measurements
- Astrophysics and Cosmic Phenomena
- Ionosphere and magnetosphere dynamics
- Metabolomics and Mass Spectrometry Studies
- Methane Hydrates and Related Phenomena
- Fungal Infections and Studies
- Peatlands and Wetlands Ecology
- Seismic Waves and Analysis
- Mass Spectrometry Techniques and Applications
- Analytical Chemistry and Chromatography
- Enzyme Structure and Function
- Digestive system and related health
- Amino Acid Enzymes and Metabolism
- Antifungal resistance and susceptibility
- Microbial Natural Products and Biosynthesis
- Earthquake Detection and Analysis
- GABA and Rice Research
- Gut microbiota and health
- Streptococcal Infections and Treatments
- Ethnobotanical and Medicinal Plants Studies
- Cannabis and Cannabinoid Research
- Seismology and Earthquake Studies
- Probiotics and Fermented Foods
- Climate change and permafrost
- Natural product bioactivities and synthesis
Pacific Northwest National Laboratory
2016-2024
Bruker (United States)
2019-2024
University of Pretoria
2007-2022
Metabolon (United States)
2022
Environmental Molecular Sciences Laboratory
2021
Albert Einstein College of Medicine
2020
Bruker (Germany)
2019
University of Johannesburg
2015
Outer membrane vesicles produced by Gram-negative bacteria have been studied for half a century but the possibility that Gram-positive secrete extracellular (EVs) was not pursued until recently due to assumption thick peptidoglycan cell wall would prevent their release environment. However, following discovery in fungi, which also walls, EVs now described variety of bacteria. purified from are implicated virulence, toxin release, and transference host cells, eliciting immune responses,...
Candida auris was first described in Japan 2009 and has now been the cause of significant outbreaks across globe. The high number isolates that are resistant to one or more antifungals, as well mortality rates from patients with bloodstream infections, attracted attention medical mycology, infectious disease, public health communities this pathogenic fungus. In current work, we performed a broad multi-omics approach on two clinical isolated New York, most affected area United States found...
Significance While peatlands have historically stored massive amounts of soil carbon, warming is expected to enhance decomposition, leading a positive feedback with climate change. In this study, unique whole-ecosystem experiment was conducted in northern Minnesota warm peat profiles 2 m deep while keeping water flow intact. After nearly y, enhanced the degradation organic matter and increased greenhouse gas production. Changes quality were accompanied by stimulation methane production...
Candida auris is a recently described multidrug-resistant pathogenic fungus that increasingly responsible for health care-associated outbreaks across the world. Bloodstream infections of this cause death in up to 70% cases. Aggravating scenario, disease-promoting mechanisms C. are poorly understood. Fungi release extracellular vesicles (EVs) carry broad range molecules, including proteins, lipids, carbohydrates, pigments, and RNA, many which virulence factors. Here, we carried out...
The full potential of the herbal market is mainly not realised due to lack knowledge chemical composition most products. growth medicine industry can only be achieved if standardised ensure proper quality control and accountability. Plant-based nuclear magnetic resonance metabolomics one such way ensuring quick reliable metabolite profiling reproducibility medicine. Nuclear resonance-based robust relatively easy use, thus that verified controlled much quicker more accurate than currently...
ATP synthase, H+ transporting, mitochondrial F1 complex, δ subunit (ATP5F1D; formerly ATP5D) is a of synthase and plays an important role in coupling proton translocation production. Here, we describe two individuals, each with homozygous missense variants ATP5F1D, who presented episodic lethargy, metabolic acidosis, 3-methylglutaconic aciduria, hyperammonemia. Subject 1, for c.245C>T (p.Pro82Leu), recurrent decompensation starting the neonatal period, subject 2, c.317T>G (p.Val106Gly),...
Abstract Sphagnum mosses dominate peatlands by employing harsh ecosystem tactics to prevent vascular plant growth and microbial degradation of these large carbon stores. Knowledge about ‐produced metabolites, their structure function, is important better understand the mechanisms, underlying this sequestration phenomenon in face climate variability. It currently unclear which compounds are responsible for inhibition organic matter decomposition mechanisms occurs. Metabolite profiling fallax...
The utility of metabolomics is well documented; however, its full scientific promise has not yet been realized due to multiple technical challenges. These grand challenges include accurate chemical identification all observable metabolites and the limiting depth-of-coverage current methods. Here, we report a combinatorial solution aid in both using UHPLC-trapped ion mobility spectrometry coupled tandem mass (UHPLC-TIMS-TOF-MS). TIMS offers additional through increased peak capacities with...
Histoplasma capsulatum is a dimorphic fungus that most frequently causes pneumonia, but can also disseminate and proliferate in diverse tissues. has complex secretion system mediates the release of macromolecule-degrading enzymes virulence factors. The formation extracellular vesicles (EVs) are an important mechanism for non-conventional both ascomycetes basidiomycetes. EVs contain proteins associated with immunologically active. Despite growing knowledge from H. other pathogenic fungi,...
Due to the recently uncovered health benefits and anti-HIV activities of dicaffeoylquinic acids (diCQAs), understanding their structures functions is great interest for drug discovery efforts. DiCQAs are analytically challenging identify quantify since they commonly exist as a diverse mixture positional geometric (cis/trans) isomers. In this work, we utilized ion mobility spectrometry coupled with mass separate various isomers before after UV irradiation. The experimental collision cross...
Warming-induced permafrost thaw could enhance microbial decomposition of previously stored soil organic matter (SOM) to carbon dioxide (CO2) and methane (CH4), one the most significant potential feedbacks from terrestrial ecosystems atmosphere in a changing climate. The environmental parameters regulating microbe-organic interactions greenhouse gas (GHG) emissions peatlands are however still largely unknown. objective this work is understand controls on SOM degradation its impact GHG across...
The rise of infection caused by 'superbugs' is alarming and one the most problematic resistant bacteria methicillin-resistant Staphylococcus aureus (MRSA). This bacterium can cause a range ailments like pneumonia, mastitis, meningitis, urinary tract infection, post operational infection. Ten medicinal plants were investigated for their efficacy against drug-sensitive drug-resistant strains S. aureus. Ethanol extracts Melianthus comosus Vahl (Melianthaceae), major L Dodonaea viscosa Jacq....
Cryptococcus neoformans is an encapsulated yeast that causes disease mainly in immunosuppressed hosts. It considered a facultative intracellular pathogen because of its capacity to survive and replicate inside phagocytes, especially macrophages. This ability heavily dependent on various virulence factors, particularly the glucuronoxylomannan (GXM) component polysaccharide capsule. Inflammasome activation phagocytes usually protective against fungal infections, including cryptococcosis....
Helichrysum species are widely used in traditional medicine with potential against infectious diseases. Extraction of the aerial parts 32 was done using polar (methanol:water (1:1)) and non-polar (hexane, dichloromethane acetone) solvent systems. Anti-human immunodeficiency virus (HIV) bioassays revealed that extracts H. mimetes chrysargyrum (2.5 μg/mL), cephaloideum (25 μg/mL) zeyheri, setosum, platypterum kraussii at had greater than 90% inhibitory activity. The extract (100 exhibited...
Metabolomics—the endpoint of the omics cascade—is increasingly recognized as a preferred method for understanding ultimate responses biological systems to stress. Flow injection electrospray (FIE) mass spectrometry (MS) has advantages untargeted metabolic fingerprinting due its simplicity and capability high-throughput screening but requires high-resolution spectrometer resolve metabolite features. In this study, we developed validated highly reproducible metabolomics platform integrating...
Abstract Peatlands, which store one third of the terrestrial carbon (C), are subject to large disturbances under a changing climate. It is crucial understand how microbial and physiochemical factors affect vulnerability these C stores predict climate‐induced greenhouse gas fluxes. Here, we used combination mass spectrometry spectroscopy techniques, sequential biotic abiotic degradation pathways Sphagnum fallax leachate in an anaerobic incubation experiment, presence absence microorganisms....
Chemical investigations of a marine sponge-associated Bacillus revealed six new imidazolium-containing compounds, bacillimidazoles A–F (1–6). Previous reports related natural products are rare. Initially unveiled by timsTOF (trapped ion mobility spectrometry) MS data, extensive HRMS and 1D 2D NMR analyses enabled the structural elucidation 1–6. In addition, plausible biosynthetic pathway to is proposed based on isotopic labeling experiments invokes highly reactive glycolytic adduct...
Herbivory in some Nicotiana species is known to induce alkaloid production. This study examined herbivore-induced defenses the nornicotine-rich African tobacco N. africana, only indigenous Africa. We tested predictions that: 1) africana will have high constitutive levels of leaf, flower and nectar alkaloids; 2) leaf herbivory by bollworm Helicoverpa armigera increased leaves, flowers nectar; 3) concentrations herbivore-damaged plants negatively affect larval growth. grew large pots a...
Natural organic matter (NOM) is composed of a highly complex mixture thousands compounds which, historically, proved difficult to characterize. However, understand the thermodynamic and kinetic controls on greenhouse gas (carbon dioxide [CO2] methane [CH4]) production resulting from decomposition NOM, molecular-level characterization coupled with microbial proteome analyses necessary. Further, climate environmental changes are expected perturb natural ecosystems, potentially upsetting...