A5004621734- Photosynthetic Processes and Mechanisms
- Cellular transport and secretion
- Drug Transport and Resistance Mechanisms
- Calcium signaling and nucleotide metabolism
- Algal biology and biofuel production
- RNA Interference and Gene Delivery
- Amino Acid Enzymes and Metabolism
- Lipid Membrane Structure and Behavior
- Autophagy in Disease and Therapy
- Metalloenzymes and iron-sulfur proteins
- Photoreceptor and optogenetics research
- Protist diversity and phylogeny
- Hemoglobin structure and function
- bioluminescence and chemiluminescence research
- Mitochondrial Function and Pathology
- Lysosomal Storage Disorders Research
- Microbial Community Ecology and Physiology
- Bacterial Genetics and Biotechnology
- Spectroscopy and Quantum Chemical Studies
- ATP Synthase and ATPases Research
- Metal-Catalyzed Oxygenation Mechanisms
- Plant Stress Responses and Tolerance
- Trace Elements in Health
Osnabrück University
2021-2025
University of Tübingen
2018-2020
Max Planck Institute of Biophysics
2020
Czech Academy of Sciences, Institute of Microbiology
2018
Lysosomes are essential for cellular recycling, nutrient signaling, autophagy, and pathogenic bacteria viruses invasion. Lysosomal fusion is fundamental to cell survival requires HOPS, a conserved heterohexameric tethering complex. On the membranes be fused, HOPS binds small membrane-associated GTPases assembles SNAREs fusion, but how complex fulfills its function remained speculative. Here, we used cryo-electron microscopy reveal structure of HOPS. Unlike previously reported, significant...
Abstract Cells depend on their endolysosomal system for nutrient uptake and downregulation of plasma membrane proteins. These processes rely endosomal maturation, which requires multiple fusion steps. Early endosome is promoted by the Rab5 GTPase its effector, hexameric CORVET tethering complex, homologous to lysosomal HOPS. How these related complexes recognize specific target membranes remains entirely elusive. Here, we solve structure cryo-electron microscopy revealed minimal requirements...
Fusion at the lysosome (or yeast vacuole) requires conserved hexameric HOPS tethering complex. binds to vacuolar Rab7-like GTPase Ypt7 via its subunits Vps41 and Vps39 supports fusion by promoting SNARE assembly. In contrast sister complex CORVET, Ypt7-interacting domain of in is connected core a long, extended α-solenoid domain. Here, we show that this solenoid acts as molecular ruler position Ypt7-interaction part relative support function. Mutant complexes with shortened or still tether...
The oxidative pentose phosphate (OPP) pathway is a fundamental carbon catabolic route for generating reducing power and metabolic intermediates biosynthetic processes. In addition, its first two reactions form the OPP shunt, which replenishes Calvin-Bassham cycle under certain conditions. Glucose-6-phosphate dehydrogenase (G6PDH) catalyzes rate-limiting reaction of this route. photosynthetic organisms, G6PDH redox-regulated to allow fine-tuning prevent futile cycles while being fixed....
Abstract High-resolution structure determination of membrane proteins typically requires isolation from the native lipid bilayer and reconstitution into artificial mimics. For this purpose, numerous detergents, amphipols, polymers scaffold are available. The choice specific substitute can strongly affect protein’s activity, stability conformational spectrum, potentially leading to errors or misinterpretation during analysis. bacterial ATP-binding cassette transporter MsbA is a prominent...
Anabaena sp. PCC 7120 is a filamentous cyanobacterium able to fix atmospheric nitrogen in semi-regularly spaced heterocysts. For correct heterocyst function, special cell envelope consisting of glycolipid layer and polysaccharide essential. We investigated the role genes hgdB hgdC, encoding domains putative ABC transporter, maturation. subcellular localization fusion protein HgdC-GFP followed differential expression hgdC during Using single recombination approach, we created mutant gene...
Abstract The nitrogenase complex in the heterocysts of filamentous freshwater cyanobacterium Anabaena sp. PCC 7120 fixes atmospheric nitrogen to allow diazotrophic growth. heterocyst cell envelope protects from oxygen and consists a polysaccharide glycolipid layer that are formed by process involving recruitment different proteins. Here, we studied function putative nucleoside‐diphosphate‐sugar epimerase HgdA, which along with HgdB HgdC is essential for deposition growth without combined...
<title>Abstract</title> High-resolution structure determination of membrane proteins typically requires isolation from the native lipid bilayer and reconstitution into artificial mimics. For this purpose, numerous detergents, amphipols, polymers scaffold are available. The choice specific substitute can strongly affect protein’s activity, stability conformational spectrum, potentially leading to errors or misinterpretation during analysis. bacterial ATP-binding cassette transporter MsbA is a...
The oxidative pentose phosphate (OPP) pathway is a fundamental carbon catabolic route for generating reducing power and metabolic intermediates biosynthetic processes. In addition, its first two reactions form the OPP shunt, which replenishes Calvin-Benson cycle under certain conditions. Glucose-6-phosphate dehydrogenase (G6PDH) catalyzes rate-limiting reaction of this route. photosynthetic organisms, G6PDH redox-regulated to allow fine-tuning prevent futile cycles while being fixed....
The filamentous heterocyst-forming cyanobacterium Anabaena sp. PCC 7120 is an important model organism for studying cell differentiation, nitrogen fixation, and photosynthesis. This possesses a high number of membrane transporters. Not much known about the roles transporters, especially ATP-binding cassette (ABC) in multidrug resistance this cyanobacterium. In present work, we performed mutational analysis genes alr4280/alr4281/alr4282 alr3647/alr3648/alr3649 that code components putative...
Acid stress is an environmental problem for plants and fresh water cyanobacteria like the filamentous, heterocyst forming species Anabaena sp. PCC 7120 (hereafter sp.). Heterocyst differentiation, cell-cell communication nitrogen fixation has been deeply studied in this model organism, but little known about cellular response of to decreased pH values, causing acid stress. ATP-binding cassette (ABC) transporters are involved other bacteria, by exporting proteins responsible survival under...
Abstract Cells depend on their endolysosomal system for nutrient uptake and downregulation of plasma membrane proteins. These processes rely endosomal maturation, which requires multiple fusion steps. Early endosome is promoted by the Rab5 GTPase its effector, hexameric CORVET tethering complex, homologous to lysosomal HOPS. How these related complexes recognize specific target membranes remains entirely elusive. Here, we solved structure cryo-electron microscopy revealed minimal...
Abstract Lysosomes are of central importance in cellular recycling, nutrient signaling 1,2 and endocytosis, tightly connected to autophagy 3 the invasion pathogenic bacteria viruses 1,4 . Lysosomal fusion events fundamental cell survival require HOPS, a conserved heterohexameric tethering complex 5,6 HOPS recognizes binds small membrane-associated GTPases on lysosomes organelles, assembles membrane bound SNAREs for 7,8 Through tethering, brings membranes close proximity each other...
The nitrogenase complex in the heterocysts of filamentous freshwater cyanobacterium Anabaena sp. PCC 7120 fixes atmospheric nitrogen to allow diazotrophic growth. heterocyst cell envelope protects from oxygen and consists a polysaccharide glycolipid layer that are formed by process involving recruitment different proteins. Here we studied function putative nucleoside-diphosphate-sugar epimerase HgdA, which along with HgdB HgdC is essential for deposition growth without combined source. Using...
Abstract Magnesium chelatase is a conserved enzyme complex responsible for the first committed step of chlorophyll biosynthesis in photosynthetic organisms, which addition magnesium to precursor, protoporphyrin IX. The composed catalytic subunit ChlH, bridging ChlD, and ChlI, serves as motor that drives entire complex. Although well-characterized functionally, high-resolution structures are available only individual subunits. Hence, full assembly molecular mechanism remains unknown. Here, we...
Photosynthesis is an essential life process that relies on chlorophyll. In photosynthetic organisms, chlorophyll synthesis involves multiple steps and depends magnesium chelatase. This enzyme complex responsible for inserting into the precursor, but molecular mechanism of this not fully understood. By using cryogenic electron microscopy conducting functional analyses, we have discovered motor subunit ChlI chelatase undergoes conformational changes in presence ATP. Our findings offer new...