Publications by authors named "Hochstrasser R"

Cell-free enzymatic assays are highly useful tools in early compound profiling due to their robustness and scalability. However, their inadequacy to reflect the complexity of target engagement in a cellular environment may lead to a significantly divergent pharmacology that is eventually observed in cells. The discrepancy that emerges from properties like permeability and unspecific protein binding may largely mislead lead compound selection to undergo further chemical optimization.

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Two six-month old female Lacaune lambs with severe skeletal malformations of both front limbs were presented to the Department of Farm Animals, University of Zurich. The clinical examination showed alert animals with a high body weight and body condition score as well as a valgus deformation without pain or swelling. Radiographic examination showed severe irregularities in the epiphysial plate of the metacarpal bones in both lambs.

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Alzheimer's Disease (AD) is the most widespread form of dementia, with one of the pathological hallmarks being the formation of neurofibrillary tangles (NFTs). These tangles consist of phosphorylated Tau fragments. Asparagine endopeptidase (AEP) is a key Tau cleaving enzyme that generates aggregation-prone Tau fragments.

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The environmental bacterium Legionella pneumophila causes the pneumonia Legionnaires' disease. The opportunistic pathogen forms biofilms and employs the Icm/Dot type IV secretion system (T4SS) to replicate in amoebae and macrophages. A regulatory network comprising the Legionella quorum sensing (Lqs) system and the transcription factor LvbR controls bacterial motility, virulence and biofilm architecture.

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species are facultative intracellular pathogens that cause a life-threatening pneumonia termed Legionnaires' disease. Legionella pneumophila employs the Lqs-LvbR ( quorum sensing- virulence and biofilm regulator) network to regulate virulence and motility, but its role for growth in media is ill-defined. Here, we report that compared to the L.

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The Gram-negative bacterium Legionella pneumophila is the causative agent of Legionnaires' disease and replicates in amoebae and macrophages within a distinct compartment, the Legionella-containing vacuole (LCV). The facultative intracellular pathogen switches between a replicative, non-virulent and a non-replicating, virulent/transmissive phase. Here, we show on a single-cell level that at late stages of infection, individual motile (P -GFP-positive) and virulent (P - and P -GFP-positive) L.

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Aldosterone synthase (CYP11B2) inhibitors have been explored in recent years as an alternative therapeutic option to mineralocorticoid receptor (MR) antagonists to reduce elevated aldosterone levels, which are associated with deleterious effects on various organ systems including the heart, vasculature, kidney, and central nervous system (CNS). A benzamide pyridine hit derived from a focused screen was successfully developed into a series of potent and selective 3-pyridyl isoindolin-1-ones CYP11B2 inhibitors. Our systematic structure-activity relationship study enabled us to identify unique structural features that result in high selectivity against the closely homologous cortisol synthase (CYP11B1).

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Bacterial gene regulation occurs through complex networks, wherein linear systems respond to intracellular or extracellular cues and engage on vivid crosstalk. The ubiquitous water-borne bacterium Legionella pneumophila colonizes various distinct environmental niches ranging from biofilms to protozoa, and - as an 'accidental' pathogen - the human lung. Consequently, L.

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The water-borne bacterium Legionella pneumophila replicates in environmental protozoa and upon inhalation destroys alveolar macrophages, thus causing a potentially fatal pneumonia termed 'Legionnaires' disease'. L. pneumophila employs the Legionella quorum sensing (Lqs) system to control its life cycle, pathogen-host cell interactions, motility and natural competence.

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The amoeba-resistant bacterium Legionella pneumophila infects humans through aerosols and thereby can cause a life-threatening pneumonia termed Legionnaires' disease. In the environment L. pneumophila forms and colonizes biofilms, which usually comprise complex multispecies communities.

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The causative agent of Legionnaires' disease, Legionella pneumophila, colonizes amoebae and biofilms in the environment. The opportunistic pathogen employs the Lqs (Legionella quorum sensing) system and the signalling molecule LAI-1 (Legionella autoinducer-1) to regulate virulence, motility, natural competence and expression of a 133 kb genomic "fitness island", including a putative novel regulator. Here, we show that the regulator termed LvbR is an LqsS-regulated transcription factor that binds to the promoter of lpg1056/hnox1 (encoding an inhibitor of the diguanylate cyclase Lpg1057), and thus, regulates proteins involved in c-di-GMP metabolism.

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The importance of Discoidin Domain Receptor 1 (DDR1) in renal fibrosis has been shown via gene knockout and use of antisense oligonucleotides; however, these techniques act via a reduction of DDR1 protein, while we prove the therapeutic potential of inhibiting DDR1 phosphorylation with a small molecule. To date, efforts to generate a selective small-molecule to specifically modulate the activity of DDR1 in an in vivo model have been unsuccessful. We performed parallel DNA encoded library screens against DDR1 and DDR2, and discovered a chemical series that is highly selective for DDR1 over DDR2.

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Between September 2016 and February 2017 a survey in Swiss deer farms were conducted to gain information about their husbandry. Questions about the business, feeding, management, health and deworming strategies were asked. 98 (19%) out of 527 registered farms (2016) participated in the survey.

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Bialaphos resistance (BAR) and phosphinothricin acetyltransferase (PAT) genes, which convey resistance to the broad-spectrum herbicide phosphinothricin (also known as glufosinate) via N-acetylation, have been globally used in basic plant research and genetically engineered crops . Although early in vitro enzyme assays showed that recombinant BAR and PAT exhibit substrate preference toward phosphinothricin over the 20 proteinogenic amino acids , indirect effects of BAR-containing transgenes in planta, including modified amino acid levels, have been seen but without the identification of their direct causes . Combining metabolomics, plant genetics and biochemical approaches, we show that transgenic BAR indeed converts two plant endogenous amino acids, aminoadipate and tryptophan, to their respective N-acetylated products in several plant species.

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To optimize future DNA-encoded library design, we have attempted to quantify the library size at which the signal becomes undetectable. To accomplish this we (i) have calculated that percent yields of individual library members following a screen range from 0.002 to 1%, (ii) extrapolated that ∼1 million copies per library member are required at the outset of a screen, and (iii) from this extrapolation predict that false negative rates will begin to outweigh the benefit of increased diversity at library sizes >10.

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The ubiquitous Gram-negative bacterium parasitizes environ mental amoebae and, upon inhalation, replicates in alveolar macrophages, thus causing a life-threatening pneumonia called "Legionnaires' disease." The opportunistic pathogen employs a bi-phasic life cycle, alternating between a replicative, non-virulent phase and a stationary, transmissive/virulent phase. employs the Lqs ( quorum sensing) system as a major regulator of the growth phase switch.

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Background: In a recent acupuncture study, volunteers were able to sense stimulation by ‘therapeutic Qi' even when mechanical and psychological causes were excluded. Here, we investigated if ‘therapeutic Qi' also influences the heart rate variability.

Methods: This was a controlled, randomized, single-blind crossover study with 30 volunteers.

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So far, most research attempts to explain the mechanism of the action of acupuncture have focused mostly on mechanically-triggered active factors and have produced inconclusive findings. In this study, we investigate whether acupuncture might also involve nonmechanical, nonpsychological active factors originating in the therapist. In 30 individuals, an acupuncture needle was inserted in the acupoint PC6 using a special device without touching the needle.

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Unlabelled: The general stress response (GSR) allows bacteria to monitor and defend against a broad set of unrelated, adverse environmental conditions. In Alphaproteobacteria, the key step in GSR activation is phosphorylation of the response regulator PhyR. In Sphingomonas melonis Fr1, seven PhyR-activating kinases (Paks), PakA to PakG, are thought to directly phosphorylate PhyR under different stress conditions, but the nature of the activating signals remains obscure.

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The general stress response (GSR) in Alphaproteobacteria was recently shown to be controlled by a partner-switching mechanism that is triggered by phosphorylation of the response regulator PhyR. Activation of PhyR ultimately results in release of the alternative extracytoplasmic function sigma factor σ(EcfG), which redirects transcription toward the GSR. Little is known about the signal transduction pathway(s) controlling PhyR phosphorylation.

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Water is an integral part of the homotetrameric M2 proton channel of the influenza A virus, which not only assists proton conduction but could also play an important role in stabilizing channel-blocking drugs. Herein, we employ two dimensional infrared (2D IR) spectroscopy and site-specific IR probes, i.e.

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Drug discovery is a multifaceted endeavor encompassing as its core element the generation of structure-activity relationship (SAR) data by repeated chemical synthesis and biological testing of tailored molecules. Herein, we report on the development of a flow-based biochemical assay and its seamless integration into a fully automated system comprising flow chemical synthesis, purification and in-line quantification of compound concentration. This novel synthesis-screening platform enables to obtain SAR data on b-secretase (BACE1) inhibitors at an unprecedented cycle time of only 1 h instead of several days.

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The design and synthesis of alanine-rich α-helical peptides constrained in a partially unfolded state by incorporation of the S,S-tetrazine phototrigger has been achieved, permitting, upon photochemical release, observation by 2D-IR spectroscopy of the subnanosecond conformational dynamics that govern the early steps associated with α-helix formation. Solid-phase peptide synthesis was employed to elaborate the requisite fragments, with full peptide construction via solution-phase fragment condensation. The fragment union tactic was also employed to construct (13)C═(18)O isotopically edited amides to permit direct observation of conformational motion at or near specific peptide bonds.

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Molecular ions undergoing ultrafast conformational changes on the same time scale of water motions are of significant importance in condensed phase dynamics. However, the characterization of systems with fast molecular motions has proven to be both experimentally and theoretically challenging. Here, we report the vibrational dynamics of the non-degenerate (C12,C13)-oxalate anion, an ultrafast rotor, in aqueous solution.

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The relaxation of helical structures very close to equilibrium is observed via transient 2D IR spectroscopy. An initial distribution of synthetically distorted helices having an unnatural bridge linking the 10th and 12th residues of an alanine-rich α-helix is released to evolve into the equilibrium distribution of α-helix conformations. The bridge constrains the structure to be slightly displaced from the full α-helix equilibrium near these residues, yet the peptide is not unfolded completely.

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