Publications by Horst Arthur Vogel

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

Biological cells continuously change shape allowing essential functions such as cell motility, vesicle-mediated release/uptake of soluble and membrane components or nanotube-mediated cell–cell communications. Here we use single cell micromanipulation to in ...

The secondary structure of lactose permease (I) of Escherichia coli reconstituted in lipid membranes was detd. by Raman spectroscopy. The a-helix content was .apprx.70%, the b-strand content was

This paper presents a switched-capacitor (SC) current integrator circuit for impedance measurement of tethered bilayer lipid membrane (tBLM) biosensors. The circuit comprises a small number of high performance components enabling enhanced experimental flex ...

G-protein-coupled receptors (GPCRs) are important targets for treating severe diseases. However why certain molecules act as activators whereas others, with similar structures, block GPCR activation, is poorly understood since the same molecule can activat ...

A new method is presented for measuring sensitively the interactions between ligands and their membrane-bound receptors in situ by using integrated optics, thus avoiding the need for addnl. labels. Phospholipid bilayers were attached covalently to waveguides by a novel protocol that can in principle be used with any glass-like surface. In a first step, phospholipids carrying head-group thiols were covalently immobilized onto SiO2-TiO2 waveguide surfaces. This was accomplished by acylation of aminated wavegu

ClC-2 transports chloride ions across plasma membranes and plays critical roles in cellular homeostasis. Its dysfunction is involved in diseases including leukodystrophy and primary aldosteronism. AK-42 was recently reported as a specific inhibitor of ClC- ...

Despite the importance of trafficking for regulating G protein-coupled receptor signaling, for many members of the seven transmembrane helix protein family, such as odorant receptors, little is known about this process in live cells. Here, the complete lif ...

Analysis of genetic and functional variability in populations of living cells requires experimental techniques capable of monitoring cellular processes such as cell signaling of many single cells in parallel while offering the possibility to sort interesti ...

The mouse serotonin 5-HT3A receptor is a homo-pentameric ligand-gated ion channel (pLGIC) mediating fast excitatory neurotransmission in the central nervous system. The molecular mechanism of ion permeation of 5-HT3A receptors triggered by the neurotransmi ...

The outer membrane protein OmpF from Escherichia coli is a member of a large family of b-barrel membrane proteins. Some, like OmpF, are pore-forming proteins while others are active transporters or enzymes. We have previously shown that the receptor-binding domain (R-domain) of the toxin colicin N binds with high affinity to OmpF reconstituted into tethered lipid bilayers on gold electrodes. The binding can be measured by surface plasmon resonance (SPR) and ion channel blockage (impedance spectroscopy, IS).

The coat protein of bacteriophage Pf3 forms discrete and stable ion channels of uniform size in planar bilayers of asolectin. Its primary sequence suggests a channel formed by a bundle of transmembrane helixes. Since the apparent transmembrane region only consists of strongly hydrophobic residues, it represents a new class of channel-forming proteins. The channel activity is strongly voltage-dependent. The single-channel conductance of 60 pS (at 100 mV) in 0.2 M NaCl is slightly voltage-dependent, indicatin

The secondary structure of alamethicin in lipid membranes below and above the lipid phase transition temp. Tt is detd. by Raman spectroscopy and CD measurements. In both cases structural data are obtained by fitting the exptl. spectra by a superposition of the spectra of 15 ref. proteins of known 3-dimensional structure. According to the Raman expts., in a lipid bilayer above Tt, alamethicin is helical from residue 1 to 12, whereas below Tt the helix extends from residue 1 to 16. The remaining C-terminal pa

The mol. self-organization and structural properties of peptide assemblies at different interfaces, using either amphipathic or hydrophobic polypeptide helixes, is described. The two peptides under investigation form stable monolayers on the water surface under the conservation of their mol. conformation, as studied by CD and polarization-modulation Fourier transform IR (FTIR) spectroscopy. Using surface plasmon resonance and reflection-absorption FTIR, we show that such mol. layers can be transferred unalt

Rhodopsin-transducin coupling was used as an assay to investigate a laterally patterned membrane reconstituted with a receptor and its G protein. It served as a model system to show the feasibility to immobilize G protein-coupled receptors on solid supports and investigate receptor activation and interaction with G proteins by one-dimensional imaging surface plasmon resonance. Supported membranes were formed by the self-assembly of lipids and rhodopsin from detergent soln. onto functionalized gold surfaces.

Cell-membrane sheets suitable for in-vitro functional fluorescence studies have been prepd. by direct detachment from cell membranes using poly-L-lysine-coated glass slides. The resulting transferred planar membranes conserve the compn. as well as most pro ...

We present an extremely versatile method for the lateral organization of nano-scale objects (NOs) based on the phenomenon of polymer demixing. NOs are suspended in a soln. of two immiscible polymers, which is used to form a thin polymer film by spin coating. During spin coating the two polymers sep. to give a microphase structure, whose length scale depends on the exptl. conditions. The NOs spontaneously partition into one or other of the polymer phases resulting in their lateral organization. In this work,

Traditional drug discovery processes are typically expensive, time-consuming, and have a very high failure rate. Artificial intelligence (AI) is currently reshaping this field in unprecedented ways, promising to significantly improve the efficiency and success rate of drug development. This article systematically compares and analyzes the application of AI for two major drug types: small molecule vs. peptide drugs. It explores their applications in several key stages of drug development, including virtual s

Tethered lipid bilayers, containing a transmembrane synthetic ligand-gated ion channel (SLIC), have been formed on gold surfaces. The SLIC was designed as a highly selective receptor and reporter protein to detect antibodies in whole blood, which are of im ...

Cellular signalling is classically investigated by measuring optical or electrical properties of single or populations of living cells. Here we show how cell-derived vesicles can be used for anlaysing transmembrane signalling. The vesicles are derived from live mammalian cells by using either chemicals, or by optical tweezers and they comprise parts of the plasma membrane and cytosol of the mother cell. We measured in vesicles derived from individual cells with single molecule sensitivity the different step

The secondary structure of bacterio-opsin (BO), the retinal free protein-component of bacteriorhodopsin (BR), was detd. by Raman spectroscopy. Addnl. CD measurements revealed only negligible conformational differences between BO in apomembranes and BR in purple membranes. Therefore, the secondary structure of BR was derived from the Raman data of BO. The protein conformation consists of 72-82% helixes, 2-11% b-strands, and 11-17% b-turns. Only about half of the helical structures correspond to aI-helixes, t

Horst Arthur Vogel

Chat with Graph Search

Membrane nanotubes drawn by optical tweezers transmit electrical signals between mammalian cells over long distances

The structure of the lactose permease derived from Raman spectroscopy and prediction methods

Real-time high-sensitivity impedance measurement interface for tethered BLM biosensor arrays

The Mechanism of Ligand-Induced Activation or Inhibition of - and -Opioid Receptors

Covalent attachment of functionalized lipid bilayers to planar waveguides for measuring protein binding to biomimetic membranes

Cryo-EM structures of ClC-2 chloride channel reveal the blocking mechanism of its specific inhibitor AK-42

Visualizing odorant receptor trafficking in living cells down to the single-molecule level

Microfluidic array cytometer based on refractive optical tweezers for parallel trapping, imaging and sorting of individual cells

Two-dimensional crystallization of the mouse serotonin 5-HT3A receptor

Stable self-assembly of a protein engineering scaffold on gold surfaces

Pf3 coat protein forms voltage-gated ion channels in planar lipid bilayers

Comparison of the conformation and orientation of alamethicin and melittin in lipid membranes

Formation of stable polypeptide monolayers at interfaces: controlling molecular conformation and orientation

Incorporation of Rhodopsin in Laterally Structured Supported Membranes: Observation of Transducin Activation with Spatially and Time-Resolved Surface Plasmon Resonance

Supported cell-membrane sheets for functional fluorescence imaging of membrane proteins

Organization of nanoscale objects via polymer demixing

A Comparative Review of Artificial Intelligence Applications in Small Molecule Versus Peptide Drug Discovery

A synthetic membrane protein in tethered lipid bilayers for immunosensing in whole blood

Cell-derived plasma membrane vesicles as minimal cells for analyzing transmembrane signaling

The secondary structure of bacteriorhodopsin determined by Raman and circular dichroism spectroscopy