A5006134761- Photosynthetic Processes and Mechanisms
- Plant nutrient uptake and metabolism
- Plant Stress Responses and Tolerance
- Plant Molecular Biology Research
- RNA modifications and cancer
- Redox biology and oxidative stress
- Legume Nitrogen Fixing Symbiosis
- Enzyme Structure and Function
- Amino Acid Enzymes and Metabolism
- Viral Infectious Diseases and Gene Expression in Insects
- Advanced Proteomics Techniques and Applications
- Plant Micronutrient Interactions and Effects
- Endoplasmic Reticulum Stress and Disease
- Plant responses to water stress
- Islanding Detection in Power Systems
- Electron Spin Resonance Studies
- Genetic and Kidney Cyst Diseases
- Polysaccharides and Plant Cell Walls
- Protist diversity and phylogeny
- Fungal and yeast genetics research
- Neural dynamics and brain function
- Drug Transport and Resistance Mechanisms
- Porphyrin Metabolism and Disorders
- Methane Hydrates and Related Phenomena
- Clostridium difficile and Clostridium perfringens research
Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau
2023
University of Kaiserslautern
2010-2022
University of Würzburg
2010
University of Stuttgart
2010
Weizmann Institute of Science
2009
The tonoplast monosaccharide transporter (TMT) family comprises three isoforms in Arabidopsis thaliana, and TMT-green fluorescent protein fusion proteins are targeted to the vacuolar membrane. TMT promoter-beta-glucuronidase plants revealed that TONOPLAST MONOSACCHARIDE TRANSPORTER1 (TMT1) TMT2 genes exhibit a tissue- cell type-specific expression pattern, whereas TMT3 is only weakly expressed. TMT1 induced by drought, salt, cold treatments sugar. During adaptation, tmt knockout lines...
Abstract The extent to which vacuolar sugar transport activity affects molecular, cellular, and developmental processes in Arabidopsis (Arabidopsis thaliana) is unknown. Electrophysiological analysis revealed that overexpression of the tonoplast monosaccharide transporter TMT1 a tmt1-2::tDNA mutant led increased proton-coupled import into isolated mesophyll vacuoles comparison with wild-type vacuoles. overexpressor mutants grew faster than plants on soil high-glucose (Glc)-containing liquid...
Copper is an essential micronutrient for all organisms because it serves as a cofactor of several proteins involved in electron transfer. Elevated copper concentrations can cause toxic effects and have established suitable mechanisms to regulate the uptake internal distribution balance content at optimal concentration. In recent studies, family transporters (COPT) with high homology other eukaryotic (Ctr) has been identified Arabidopsis thaliana. this study we clarified physiological...
Because they are immotile organisms, higher plants have developed efficient strategies for adaptation to temperature changes. During cold acclimation, accumulate specific types of solutes enhance freezing tolerance. The vacuole is a major solute storage organelle, but until now the role tonoplast proteins in acclimation has not been investigated. In comparative proteome analysis, we identified several membrane with altered abundance upon acclimation. We found an increased protein...
Sucrose (Suc) is one of the most important types sugars in plants, serving inter alia as a long-distance transport molecule, carbon and energy storage compound, an osmotically active solute, fuel for many anabolic reactions. Suc biosynthesis degradation pathways are well known; however, regulation intracellular distribution poorly understood. In particular, cellular function chloroplast reserves transporters involved accumulating these substantial levels remain uncharacterized. Here, we...
Abstract Plants represent an important source of molybdenum in the human diet. Recently, MOT1 has been identified as a transport protein responsible for molybdate import Arabidopsis thaliana L.; however, function homologous MOT2 not resolved. Interestingly, MOT2‐GFP analysis indicated vacuolar location this carrier protein. By site directed mutagenesis at N‐terminal end MOT2, we di‐leucine motif that is essential driving into membrane. Molybdate quantification isolated vacuoles showed...
Summary Arabidopsis vacuoles harbor, besides sugar transporter of the TMT ‐type, an early response to dehydration like 6 ( ERDL 6) protein involved in glucose export into cytosol. However, mode transport and plant's feedback overexpression its activity on essential properties such as, for example, seed germination or freezing tolerance, remain unexplored. Using patch‐clamp studies expressing At we demonstrated directly that this carrier operates as a proton‐driven exporter. Overexpression Bv...
Acclimation is the capacity to adapt environmental changes within lifetime of an individual. This ability allows plants cope with continuous variation in ambient conditions which they are exposed as sessile organisms. Because and extremes becoming even more pronounced due current period climate change, enhancing efficacy plant acclimation a promising strategy for mitigating consequences global warming on crop yields. At cellular level, chloroplast plays central role many responses, acting...
Summary Vacuolar solute accumulation is an important process during plant development, growth and stress responses. Although several vacuolar carriers have been identified recently, knowledge regarding the regulation of transport still limited. Solute may be controlled by various factors, such as alterations in carrier abundance or activity. Phosphorylation via kinases a well‐known principle for activation deactivation proteins. Several phosphorylated proteins tonoplast proteome; however,...
Specific generation of reactive oxygen species (ROS) is important for signalling and defence in many organisms. In plants, different types ROS perform useful biological functions the extracellular space (apoplast) supporting processes such as polymerisation cell wall remodelling. addition, increased formation superoxide hydrogen peroxide occurs during immune responses. Our current knowledge apoplastic dynamics based on luminescence assays, staining methods indirect evidence via changes to...
Energy parasitism by ATP/ADP transport proteins is an essential, common feature of intracellular bacteria such as chlamydiae and rickettsiae, which are major pathogens humans. Although several have so far been characterized, some fundamental questions regarding their function remained unaddressed. In this study, we focused on the detailed biochemical analysis a representative transporter (PamNTT1), from amoeba symbiont Protochlamydia amoebophila (UWE25) to further clarify principle energy...
ENT1 of Arabidopsis thaliana was the first member equilibrative nucleoside transporter (ENT) family to be identified in plants and characterized as a cellular, high-affinity importer. Evidence is presented here for tonoplast localization based on proteome data Western blot analyses. Increased export adenosine from reconstituted preparations 35S:ENT1 mutants compared with those wild type ENT1-RNAi support this view. Furthermore, increased vacuolar 2′3′-cAMP (an intermediate RNA catabolism)...
The ability of plants to withstand cold temperatures relies on their photosynthetic activity. Thus, the chloroplast is utmost importance for acclimation and acquisition freezing tolerance. During acclimation, properties change markedly. To provide most comprehensive view protein repertoire envelope, we analyzed this membrane system in Arabidopsis (Arabidopsis thaliana) using mass spectrometry-based proteomics. Profiling envelope membranes was achieved by a cross comparison intensities across...
A single-chain antibody fragment directed against fimbriae of enterotoxigenic Escherichia coli was produced by recombinant Pichia pastoris under control the methanol-inducible AOX1 promoter. In high-cell-density cultivation on defined medium, methanol-limited and methanol-saturated conditions were compared. After batch fed-batch phase glycerol, methanol concentration controlled to 1% (v/v) or fed with an exponentially increasing rate. Whereas limitation impaired cell integrity product...
Structure–function relationships of the plastidic ATP/ADP transporter from Arabidopsis thaliana have been determined using site‐directed mutants at positions K155, E245, E385, and K527. These charged residues are found within highly conserved domains homologous transport proteins plants bacteria located in predicted transmembrane regions. Mutants K155 to K155E, K155R, or K155Q reduced ATP values between 4 16% wild‐type uptake, whereas ADP was always less then 3% value. Site‐directed...
Measurements of protein abundance changes are important for biological conclusions on protein-related processes such as activity or complex formation. Proteomic analyses in general almost routine tasks many laboratories, but a precise and quantitative description (absolute) require careful experimental design data quality. Today, vast choice metabolic labeling label-free quantitation protocols available, the trade-off between precision proteome coverage quantified proteins including missing...
Essential for the biological function of light-driven proton pump, bacteriorhodopsin (BR), and light sensor, sensory rhodopsin II (SRII), is coupling activated retinal chromophore to hosting protein moiety. In order explore dynamics this process we have performed ultrafast transient mid-infrared spectroscopy on isotopically labeled BR SRII samples. These include in D2O buffer, H218O medium, with 15N-labeled protein, 13C1413C15-labeled chromophore. Via observed shifts infrared difference...
Secretory production of a single-chain antibody fragment (scFv) by recombinant Pichia pastoris using the methanol inducible AOX1 promoter is limited biochemically retarded secretion, and economically high demand for pure oxygen. To address problem, adaptation phase with growth-limiting feeding glycerol before was optimized. In standard procedure short glycerol-feeding induction, scFv accumulated in supernatant only after 15 h. Conversely, started to appear immediately medium upon induction...
Vacuoles of plants fulfill various biologically important functions, like turgor generation and maintenance, detoxification, solute sequestration, or protein storage. Different types plant vacuoles (lytic versus storage) are characterized by different functional properties apparently caused a composition/abundance regulation transport proteins in the surrounding membrane, tonoplast. Proteome analyses allow identification vacuolar provide an informative basis for assigning observed processes...
Abstract Maltose, the major product of starch breakdown in Arabidopsis (Arabidopsis thaliana) leaves, exits chloroplast via maltose exporter1 MEX1. Consequently, mex1 loss-of-function plants exhibit substantial accumulation, a starch-excess phenotype and specific chlorotic during leaf development. Here, we investigated whether introduction an alternative metabolic route could suppress marked developmental defects typical for mutants. To this end, ectopically expressed chloroplasts functional...
The plant vacuole recycles proteins and RNA delivered to it by autophagy. In this study, isolating intact vacuoles from Arabidopsis plants, followed subsequent purification, deep sequencing, we provide a comprehensive characterization of vacuolar RNAome. the RNAome, detected ribosomal RNAs, transfer including those chloroplast origin, in addition small types. As autophagy is main mechanism for transport vacuole, atg5-1 mutants deficient were included our analysis. We observed severely...
Redox status of protein cysteinyl residues is mediated via glutathione (GSH)/glutaredoxin (GRX) and thioredoxin (TRX)-dependent redox cascades. An oxidative challenge can induce post-translational modifications on thiols, such as S-glutathionylation. Class I GRX are small thiol-disulfide oxidoreductases that reversibly catalyse S-glutathionylation disulfide formation. TRX GSH/GRX systems provide partial backup for each other in several subcellular compartments, but not the plastid stroma...