A5031720787- Metal-Catalyzed Oxygenation Mechanisms
- Metalloenzymes and iron-sulfur proteins
- Electron Spin Resonance Studies
- Photosynthetic Processes and Mechanisms
- Hemoglobin structure and function
- Free Radicals and Antioxidants
- Electrochemical Analysis and Applications
- Mitochondrial Function and Pathology
- Particle physics theoretical and experimental studies
- Coenzyme Q10 studies and effects
- Metal complexes synthesis and properties
- Porphyrin Metabolism and Disorders
- Cosmology and Gravitation Theories
- Ion channel regulation and function
- Diet, Metabolism, and Disease
- Enzyme Structure and Function
- Porphyrin and Phthalocyanine Chemistry
- Collagen: Extraction and Characterization
- Electrochemical sensors and biosensors
- Black Holes and Theoretical Physics
- Electrocatalysts for Energy Conversion
- Advanced battery technologies research
- Microbial metabolism and enzyme function
- Magnetism in coordination complexes
- Dark Matter and Cosmic Phenomena
Saarland University
2015-2024
Robert Bosch (Germany)
2023
Applied BioPhysics (United States)
2015
Technical University of Munich
2009-2012
Universitätsklinikum des Saarlandes
1999-2011
Max Planck Institute for Physics
2010-2011
University of Bayreuth
2008
University of Münster
2004-2008
Eastman Chemical Company (United States)
2007
Carl von Ossietzky Universität Oldenburg
1997-2004
Abstract Ferroptosis is a type of cell death caused by radical-driven lipid peroxidation, leading to membrane damage and rupture. Here we show that enzymatically produced sulfane sulfur (S 0 ) species, specifically hydropersulfides, scavenge endogenously generated free radicals and, thereby, suppress peroxidation ferroptosis. By providing for S biosynthesis, cysteine can support ferroptosis resistance independently the canonical GPX4 pathway. Our results further suggest hydropersulfides...
Efflux pump (e.g., P-gp, MRP1, and BCRP) inhibition has been recognized as a strategy to overcome multi-drug resistance improve drug bioavailability. Besides small-molecule inhibitors, surfactants such Tween 80, Cremophor EL, several Pluronics, Vitamin E TPGS (TPGS 1000) are known modulate efflux activity. Competitive of substrate binding, alteration membrane fluidity, ATPase have proposed possible mechanisms. Focusing on 1000, the aim our study was unravel inhibitory mechanism by comparing...
The benefit of the β1-adrenergic receptor (β1-AR) agonist dobutamine for treatment acute heart failure in peripartum cardiomyopathy (PPCM) is controversial. Cardiac STAT3 expression reduced PPCM patients. Mice carrying a cardiomyocyte-restricted deletion (CKO) develop PPCM. We hypothesized that STAT3-dependent signalling networks may influence response to β-AR patients and analysed this hypothesis CKO mice.Follow-up analyses 27 with severe (left ventricular ejection fraction ≤25%) revealed...
The glycyl radical (Gly-734) contained in the active form of pyruvate formate-lyase (PFL) <i>Escherichia coli</i> is generated by <i>S</i>-adenosylmethionine-dependent formate-lyase-activating enzyme (PFL activase). A 5′-deoxyadenosyl intermediate produced activase has been suggested as species that abstracts pro-<i>S</i> hydrogen glycine 734 residue PFL (Frey, M., Rothe, Wagner, A. F. V., and Knappe, J. (1994) <i>J. Biol. Chem.</i> 269, 12432–12437). To enable mechanistic investigations...
Summary Spontaneous melanoma phenotype switching is controlled by unknown environmental factors and may determine outcome responsiveness to anticancer therapy. We show that O rai1 STIM 2 are highly expressed control store‐operated C a 2+ entry in human melanoma. Lower extracellular or silencing of rai1/ caused decrease intracellular , which correlated with enhanced proliferation increased expression microphthalmia‐associated transcription factor, marker for proliferative phenotype. In...
Abstract Lipid droplet (LD) function relies on proteins partitioning between the endoplasmic reticulum (ER) phospholipid bilayer and LD monolayer membrane to control cellular adaptation metabolic changes. It has been proposed that these hairpin integrate into both membranes in a similar monotopic topology, enabling their passive lateral diffusion during emergence at ER. Here, we combine biochemical solvent-accessibility assays, electron paramagnetic resonance spectroscopy intra-molecular...
Quercetinase (QueD) of Streptomyces sp. FLA is an enzyme the monocupin family and catalyzes 2,4-dioxygenolytic cleavage flavonol quercetin. After expression queD gene in Escherichia coli, high specific QueD activity was found crude cell extracts when growth medium supplemented with NiCl2 or CoCl2, but not Mn2+, Fe2+, Cu2+, Zn2+ added. The metal occupancy Ni- Co-QueD purified from these cells ≤50%, presumably due to strong overproduction E. coli. Circular dichroism spectroscopy indicated same...
Coenzyme Q10 (CoQ10) is one of the essential components mitochondrial electron-transport chain (ETC) with primary function to transfer electrons along and protons across inner membrane (IMM). The concomitant proton gradient IMM for process oxidative phosphorylation consequently ATP production. Cytochrome P450 (CYP450) monoxygenase enzymes are known induce structural changes in a variety compounds expressed IMM. However, it unknown if CYP450 interacts CoQ10 how such an interaction would...
We show that hierarchically small vacuum expectation values of the superpotential in supersymmetric theories can be a consequence an approximate R symmetry. briefly discuss role such constants moduli stabilization and understanding huge hierarchy between Planck electroweak scales.
AimsCollateral arteries protect tissue from ischaemia. Heart rate correlates with vascular events in patients arterial obstructive disease. Here, we tested the effect of heart-rate reduction (HRR) on collateral artery growth.
Monocytes adjust deadly reactive oxygen species production by altering the subunit composition of ORAI calcium channel.
Reactive oxygen species (ROS) exhibit different spatial and temporal distributions as well concentrations in- outside the cell, thereby functioning signaling or pathogen-destroying molecules. Especially ROS H2O2 is important for patho/physiological status of an organism. Electrochemistry (EM) electron spin resonance (ESR)-based techniques allow quantification in artificial living systems, coping a concentration range from low nM up to mM. Working electrodes EM are optimized by diverse...
Barth syndrome (BTHS) is caused by mutations of the gene encoding tafazzin, which catalyzes maturation mitochondrial cardiolipin and often manifests with systolic dysfunction during early infancy. Beyond first months life, BTHS cardiomyopathy typically transitions to a phenotype diastolic preserved ejection fraction, blunted contractile reserve exercise, arrhythmic vulnerability. Previous studies traced formation reactive oxygen species (ROS). Because function ROS are regulated...
Flavonol 2,4‐dioxygenase, which catalyzes the cleavage of quercetin to carbon monoxide and 2‐protocatechuoyl‐phloroglucinol carboxylic acid, was purified from culture filtrate Aspergillus niger DSM 821 grown on rutin. It is a glycoprotein (46–54% carbohydrate) with N‐linked oligo‐mannose type glycan chains. The enzyme resolved in SDS polyacrylamide gels diffuse protein band that corresponded molecular mass 130–170 kDa. When flavonol 2,4‐dioxygenase heated, it dissociated into three peptides...
Purple acid phosphatase from sweet potatoes Ipomoea batatas (spPAP) has been purified to homogeneity and characterized using spectroscopic investigations. Matrix‐assisted laser desorption/ionization mass spectrometry analysis revealed a molecular of ≈ 112 kDa. The metal content was determined by X‐ray fluorescence synchrotron radiation. In contrast previous studies it is shown that spPAP contains Fe(III)–Zn(II) center in the active site as previously for purple red kidney bean (kbPAP)....
Significance Heme, traditionally viewed as a stable protein cofactor such in hemoglobin, also serves an acute signaling molecule and is cytotoxic at high concentrations. Here, we show that free intracellular heme potently enhances A-type potassium channel function. Such channels determine action potential frequency excitable cells, their dysfunction often contributes to pathological hyperexcitability, pain epilepsy. Binding of nanomolar concentrations the “ball-and-chain” N terminus...