A5066879109- Photoreceptor and optogenetics research
- Viral Infectious Diseases and Gene Expression in Insects
- Biofield Effects and Biophysics
- Electrocatalysts for Energy Conversion
- Spectroscopy and Quantum Chemical Studies
- Metalloenzymes and iron-sulfur proteins
- Neural dynamics and brain function
- Advanced battery technologies research
- Photosynthetic Processes and Mechanisms
- Chemical Reactions and Isotopes
- Mass Spectrometry Techniques and Applications
- Neuroscience and Neuropharmacology Research
- Electrochemical Analysis and Applications
- Molecular Sensors and Ion Detection
- Receptor Mechanisms and Signaling
- Silk-based biomaterials and applications
- Molecular Communication and Nanonetworks
- Neuroscience and Neural Engineering
- Advanced Drug Delivery Systems
- Solid-state spectroscopy and crystallography
- Light effects on plants
- Retinal Development and Disorders
- Analytical Chemistry and Sensors
- Advanced Fluorescence Microscopy Techniques
- Dental Implant Techniques and Outcomes
Freie Universität Berlin
2011-2022
Abstract Bacteriorhodopsin (bR) is a light-driven proton pump. The primary photochemical event upon light absorption isomerization of the retinal chromophore. Here we used time-resolved crystallography at an X-ray free-electron laser to follow structural changes in multiphoton-excited bR from 250 femtoseconds 10 picoseconds. Quantum chemistry and ultrafast spectroscopy were identify sequential two-photon process, leading excitation tryptophan residue flanking chromophore, as first...
Chloride transport by microbial rhodopsins is an essential process for which molecular details such as the mechanisms that convert light energy to drive ion pumping and ensure unidirectionality of have remained elusive. We combined time-resolved serial crystallography with spectroscopy multiscale simulations elucidate mechanism a chloride-pumping rhodopsin structural dynamics throughout cycle. traced transient anion-binding sites, obtained evidence how used in mechanism, identified steric...
The atomic structure of an electrodeposited Ni catalyst film is dominated by extensive di-μ-oxido bridging between NiIII/IV ions, as revealed X-ray absorption spectroscopy. surprisingly similar to that analogous Co-based and colloidal Mn-based catalysts. Structural requirements for water oxidation are discussed.
Channelrhodopsins are light-gated ion channels with extensive applications in optogenetics. Channelrhodopsin-1 from Chlamydomonas augustae (CaChR1) exhibits a red-shifted absorption spectrum as compared to Channelrhodopsin-2, which is highly beneficial for optogenetic application. The primary event the photocycle of CaChR1 involves an isomerization protein-bound retinal chromophore. Here, we apply time-resolved vibronic spectroscopy reveal electronic and structural dynamics associated first...
Bistable opsins are photopigments expressed in both invertebrates and vertebrates. These light-sensitive G-protein-coupled receptors undergo a reversible reaction upon illumination. A first photon initiates the cis to trans isomerization of retinal chromophore-attached protein through protonated Schiff base-and series transition states that eventually results formation thermally stable active Meta state. Excitation by second reverts this process recover original ground On other hand,...
Mid-IR spectroscopy is a powerful and label-free technique to investigate protein reactions. In this study, we use quantum-cascade-laser-based dual-comb probe conformational changes protonation events by single-shot experiment. By using well-characterized membrane protein, bacteriorhodopsin, provide comparison between our homebuilt tunable quantum cascade laser (QCL)-based scanning spectrometer as tools monitor irreversible reactions with high time resolution. conclusion, QCL-based infrared...
LOV (light oxygen voltage) proteins are photosensors ubiquitous to all domains of life. A variant the short protein from Dinoroseobacter shibae (DsLOV) exhibits an exceptionally fast photocycle. We performed time-resolved molecular spectroscopy on DsLOV-M49S and characterized formation thio-adduct state with a covalent bond between reactive cysteine (C72) C4a FMN. By use tunable quantum cascade laser, weak absorption change vibrational band S-H stretching vibration C57 was resolved time...
The [4Fe-4S] cluster containing scaffold complex HypCD is the central construction site for assembly of [Fe](CN)2CO cofactor precursor [NiFe]-hydrogenase. While importance well established, not much known about mechanism by which CN− and CO ligands are transferred attached to iron ion. We report an efficient expression purification system producing from E. coli with complete metal content. This enabled in-depth spectroscopic characterizations. results obtained EPR Mössbauer spectroscopy...
Channelrhodopsins (ChRs) belong to the unique class of light-gated ion channels. The structure channelrhodopsin-2 from Chlamydomonas reinhardtii (CrChR2) has been resolved, but mechanistic link between light-induced isomerization chromophore retinal and channel gating remains elusive. Replacements residues C128 D156 (DC gate) resulted in drastic effects closure. T127 is localized close Schiff base links DC gate base. homologous residue bacteriorhodopsin (T89) shown be crucial for visible...
The [4Fe-4S] cluster containing scaffold complex HypCD is the central construction site for assembly of [Fe](CN)2CO cofactor precursor [NiFe]-hydrogenase. While importance well established, not much known about mechanism by which CN– and CO ligands are transferred attached to iron ion. We developed an efficient protocol production isolation functional that facilitated detailed spectroscopic investigations. results obtained UV/Vis-, electron paramagnetic Resonance (EPR)-, Raman-,...