A5079136155- Redox biology and oxidative stress
- Malaria Research and Control
- Glutathione Transferases and Polymorphisms
- Sulfur Compounds in Biology
- Mosquito-borne diseases and control
- Endoplasmic Reticulum Stress and Disease
- Metal-Catalyzed Oxygenation Mechanisms
- Research on Leishmaniasis Studies
- Heat shock proteins research
- Toxoplasma gondii Research Studies
- Trace Elements in Health
- Trypanosoma species research and implications
- Advanced Glycation End Products research
- Mitochondrial Function and Pathology
- Fungal and yeast genetics research
- Drug Transport and Resistance Mechanisms
- Photosynthetic Processes and Mechanisms
- Parasite Biology and Host Interactions
- ATP Synthase and ATPases Research
- Invertebrate Immune Response Mechanisms
- Peptidase Inhibition and Analysis
- Parasites and Host Interactions
- Electron Spin Resonance Studies
- Enzyme Structure and Function
- Protease and Inhibitor Mechanisms
University of Kaiserslautern
2009-2025
Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau
2023-2025
University of Koblenz and Landau
2023-2024
Heidelberg University
2011-2021
University Hospital Heidelberg
2011-2012
Ludwig-Maximilians-Universität München
2007-2011
Justus-Liebig-Universität Gießen
2003-2009
UCLouvain
2009
Ludwig Cancer Research
2009
University of Michigan
2005
Abstract Glutaredoxins are key players in cellular redox homoeostasis and exert a variety of essential functions ranging from glutathione-dependent catalysis to iron metabolism. The exact structure–function relationships mechanistic differences among glutaredoxins that active or inactive standard enzyme assays have so far remained elusive despite numerous kinetic structural studies. Here, we elucidate the enzymatic mechanism showing require two distinct glutathione interaction sites for...
Glutaredoxins catalyze the reduction of disulfides and are key players in redox metabolism regulation. While important insights were gained regarding glutathione disulfide substrates, mechanism non-glutathione remains highly debated. Here we determined rate constants for individual reactions between PfGrx, a model glutaredoxin from Plasmodium falciparum, redox-sensitive green fluorescent protein 2 (roGFP2), substrate versatile tool intracellular measurements. We show that PfGrx-catalyzed...
Article7 August 2019Open Access Source DataTransparent process Hyperoxidation of mitochondrial peroxiredoxin limits H2O2-induced cell death in yeast Gaetano Calabrese orcid.org/0000-0002-2212-5280 Department for Chemistry, Institute Biochemistry, University Cologne, Germany Search more papers by this author Esra Peker Prince Saforo Amponsah Biology, Cellular Kaiserslautern, the Saarland, Saarbruecken, Michaela Nicole Hoehne Trine Riemer Marie Mai Gerd Patrick Bienert...
So-called 1-Cys peroxiredoxins (Prx) employ only one cysteine residue for the reduction of hydroperoxides and require an external thiol a reactive sulfenic acid during catalytic cycle. Hence, Prx, which often belong to structural Prx5- or Prx6-type subfamily, are potentially promiscuous enzymes that could react with variety thiols. Furthermore, dependence on affect susceptibility Prx hyperoxidation, i.e., formation sulfinic sulfonic acid. Here, we compared reaction mechanisms kinetics PfAOP...
Two novel monothiol glutaredoxins from yeast (ScGrx6 and ScGrx7) were identified analyzed in vitro. Both proteins are highly suited to study structure-function relationships of glutaredoxin subclasses because they differ all investigated so far share features with dithiol glutaredoxins. ScGrx6 ScGrx7 are, for example, the first showing an activity standard transhydrogenase assay glutathione bis-(2-hydroxyethyl)-disulfide. Steady-state kinetics cysteine-glutathione disulfide similar...
Coevolution of the malarial parasite and its human host has resulted in a complex network interactions contributing to homeodynamics host-parasite unit. As rapidly growing multiplying organism, Plasmodium falciparum depends on an adequate antioxidant defense system that is efficient despite absence genuine catalase glutathione peroxidase. Using different experimental approaches, we demonstrate P. imports redox-active protein peroxiredoxin 2 (hPrx-2, hTPx1) into cytosol. shown by confocal...
The malarial parasite Plasmodium falciparum possesses a functional thioredoxin and glutathione system comprising the dithiol-containing redox proteins (Trx) glutaredoxin (Grx), as well plasmoredoxin (Plrx), which is exclusively found in species. All three belong to superfamily share conserved Cys-X-X-Cys motif at active site. Only few of their target proteins, are likely be involved reactions, currently known. aim present study was extend our knowledge Trx-, Grx-, Plrx-interactome...
Class I glutaredoxins are enzymatically active, glutathione-dependent oxidoreductases, whilst class II typically inactive, Fe-S cluster-binding proteins. Enzymatically active harbor both a glutathione-scaffold site for reacting with glutathionylated disulfide substrates and glutathione-activator reduced glutathione. Here, using yeast ScGrx7 as model protein, we comprehensively identified characterized key residues from four distinct protein regions, well the covalently bound glutathione...
The homodimeric flavoprotein glutathione reductase (GR) is a central player of cellular redox metabolism, connecting NADPH to the large pool redox-active thiols. In this work, inhibition human GR by novel gold-phosphole inhibitor (GoPI) has been studied in vitro. Two modes are observed, reversible that competitive with GSSG followed irreversible inhibition. When ∼1 nm GoPI incubated NADPH-reduced (1.4 nm) enzyme becomes 50% inhibited. This appears be most potent stable date. Analyzing...
Glutaredoxins represent a ubiquitous family of proteins that catalyze the reduction disulfide bonds in their substrate by use reduced glutathione. In an attempt to identify full complement glutaredoxins baker's yeast, we found three so-far uncharacterized glutaredoxin-like named Grx6, Grx7, and Grx8. Grx6 Grx7 closely related monothiol are synthesized with N-terminal signal sequences. Both located cis-Golgi, thereby representing first compartment secretory pathway. contrast formerly...
Redox-sensitive green fluorescent protein 2 (roGFP2) is a valuable tool for redox measurements in living cells. Here, we demonstrate that roGFP2 can also be used to gain mechanistic insights into catalysis vivo. In vitro enzyme properties such as the rate-limiting reduction of wild type and mutant forms model peroxiredoxin PfAOP are shown correlate with ratiometrically measured degree oxidation corresponding fusion proteins. Furthermore, stopped-flow kinetic oxidative half-reaction support...
Glutathione S-transferase of the malarial parasite Plasmodium falciparum (PfGST) represents a novel class GST isoenzymes. Since architecture PfGST substrate binding site differs significantly from its human counterparts and there is only this one isoenzyme present in parasite, considered highly attractive target for antimalarial drug development. Here we report mechanistic, kinetic, structural characterization as well interaction with different ligands. Our data indicate that solution...
Two dithiol glutaredoxins (Grxs), Grx1 and Grx2, from yeast have been characterized to date. A third putative glutaredoxin-encoding gene (GRX8) has identified in silico. Here we show that deletion of GRX8 does not result a reduced growth rate under oxidative stress conditions, nor it enhance the defects Δgrx1 Δgrx2 single or double mutants. We furthermore compare enzymatic properties recombinant ScGrx8 with monothiol glutaredoxin ScGrx7. Molecular models suggest protein canonical Grx fold,...
Mitochondrial protein import (MPI) is essential for the biogenesis of mitochondria in all eukaryotes. Current models MPI are predominantly based on experiments with one group eukaryotes, opisthokonts. Although fascinating genome database-driven hypotheses evolution machineries have been published, previous experimental research non-opisthokonts usually focused analysis single pathways or components in, example, plants and parasites. In this study, we established kinetoplastid parasite...
Methylene blue and a series of recently developed 1,4-naphthoquinones, including 3-[4-(substituted)benzyl]-menadiones, are potent antimalarial agents in vitro vivo. The activity these structurally diverse compounds against the human malaria parasite Plasmodium falciparum might involve their peculiar redox properties. According to current theory, redox-active methylene 3-[4-(trifluoromethyl)benzyl]-menadione "subversive substrates." These thought shuttle electrons from reduced flavoproteins...