Metabolic dysfunction-associated steatohepatitis (MASH) is the most prevalent cause of liver disease worldwide, with a single approved therapeutic. Previous research has shown that interleukin-22 (IL-22) can suppress β-cell stress, reduce local islet inflammation, restore appropriate insulin production, reverse hyperglycemia, and ameliorate insulin resistance in preclinical models of diabetes. In clinical trials long-acting forms of IL-22 have led to increased proliferation in the skin and intestine, where the IL-22RA1 receptor is highly expressed.
View Article and Find Full Text PDFBitter taste receptors (T2R) are a subfamily of G protein-coupled receptors that enable humans to detect aversive and toxic substances. The ability to discern bitter compounds varies between individuals and is attributed mainly to naturally occurring T2R polymorphisms. T2Rs are also expressed in numerous non-gustatory tissues, including the heart, indicating potential contributions to cardiovascular physiology.
View Article and Find Full Text PDF"Reagentless" immunosensors are emerging to address the challenge of practical and sensitive detection of important biomarkers in real biological samples without the need for multistep assays and user intervention, with applications ranging from research tools to point-of-care diagnostics. Selective target binding to an affinity reagent is detected and reported in one step without the need for washing or additional reporters. In this study, we used a structure-guided approach to identify a mutation site in an antibody fragment for the polarity-dependent fluorophore, Anap, such that upon binding of the protein target cardiac troponin I, the Anap-labeled antibody would produce a detectable and dose-dependent shift in emission wavelength.
View Article and Find Full Text PDFMonoclonal antibodies (mAbs) are one of the most successful and versatile protein-based pharmaceutical products used to treat multiple pathological conditions. The remarkable specificity of mAbs and their affinity for biological targets has led to the implementation of mAbs in the therapeutic regime of oncogenic, chronic inflammatory, cardiovascular, and infectious diseases. Thus, the discovery of novel mAbs with defined functional activities is of crucial importance to expand our ability to address current and future clinical challenges.
View Article and Find Full Text PDFBiochim Biophys Acta Mol Cell Res
August 2021
The Endoplasmic Reticulum (ER) is responsible for the folding and post-translational modification of secretory proteins, as well as for triaging misfolded proteins. During folding, there is a complex yet only partially understood interplay between disulfide bond formation, which is an enzyme catalyzed event in the oxidizing environment of the ER, along with other post-translational modifications (PTMs) and chaperone-supported protein folding. Here, we used the glycoprotein torsinA as a model substrate to explore the impact of ER redox homeostasis on PTMs and protein biogenesis.
View Article and Find Full Text PDFEngineering antibodies to improve target specificity, reduce detection limits, or introduce novel functionality is an important research area for biosensor development. While various affinity biosensors have been developed to generate an output signal upon varying analyte concentrations, reversible and continuous protein monitoring in complex biological samples remains challenging. Herein, we explore the concept of directed evolution to modulate dissociation kinetics of a high affinity anti-epidermal growth factor receptor (EGFR) single-chain variable antibody fragment (scFv) to enable continuous protein sensing in a label-free binding assay.
View Article and Find Full Text PDFFront Mol Biosci
October 2020
TorsinA is a AAA+ ATPase involved in the severe neurological disease Early Onset Torsion Dystonia. Despite the impressive progress in the field in the recent years, the structural organization and function of this intriguing molecule is still not clear. One outstanding difference between torsinA and other AAA+ ATPases is that torsinA is a glycoprotein.
View Article and Find Full Text PDFIntroduction: Monoclonal antibodies have been utilized in clinical and basic research for the treatment of various malignancies. Whilst all therapeutically approved monoclonal antibodies or fragments thereof are directed against cell-surface receptors or proteins of the human secretome, intracellular antigen targeting strategies still await translation into the clinic. This contradicts the notion of antibodies being the magic bullet concept as many cancer targets are out of reach.
View Article and Find Full Text PDFTyrosinase is a copper-containing enzyme that catalyzes the biosynthesis of melanin. This enzyme is present in bacteria, fungi, plants and animals, and plays multiple roles in pigmentation, wound healing, radiation protection, primary immune responses and the undesirable browning of fruits and vegetables. Selective tyrosinase inhibitors hence have potential application in diverse areas of agriculture, cosmetics and pharmaceuticals.
View Article and Find Full Text PDFThe inhibition of tyrosinase is an established strategy for treating hyperpigmentation. Our previous findings demonstrated that cinnamic acid and benzoic acid scaffolds can be effective tyrosinase inhibitors with low toxicity. The hydroxyl substituted benzoic and cinnamic acid moieties of these precursors were incorporated into new chemotypes that displayed in vitro inhibitory effect against mushroom tyrosinase.
View Article and Find Full Text PDFHerein, we describe a fluorescent immunosensor designed by incorporating an unnatural amino acid fluorophore into the binding site of an EGFR-specific antibody fragment, resulting in quantifiable EGFR-dependent changes in peak fluorescence emission wavelength. To date, immunosensor design strategies have relied on binding-induced changes in fluorescence intensity that are prone to excitation source fluctuations and sample-dependent noise. In this study, we used a rational design approach to incorporate a polarity indicator (Anap) into specific positions of an anti-EGFR single chain antibody to generate an emission wavelength-dependent immunosensor.
View Article and Find Full Text PDFThe dissemination of multi-resistant bacteria represents an enormous burden on modern healthcare. Plasmid-borne conjugative transfer is the most prevalent mechanism, requiring a type IV secretion system that enables bacteria to spread beneficial traits, such as resistance to last-line antibiotics, among different genera. Inc18 plasmids, like the Gram-positive broad host-range plasmid pIP501, are substantially involved in propagation of vancomycin resistance from Enterococci to methicillin-resistant strains of Staphylococcus aureus.
View Article and Find Full Text PDFImmunocytokines are fusion proteins that combine the specific antigen binding capacities of an antibody or derivative thereof and the potent bioactivity of a cytokine partner. These novel biopharmaceuticals have been directed to various targets of oncological as well as non-oncological origin and a handful of promising constructs are currently advancing in the clinical trial pipeline. Several factors such as the choice of a disease specific antigen, the antibody format and the modulatory nature of the payload are crucial, not only for therapeutic efficacy and safety but also for the commercial success of such a product.
View Article and Find Full Text PDFBackground: The house dust mite (HDM) allergen Der p 18 belongs to the glycoside hydrolase family 18 chitinases. The relevance of Der p 18 for house dust mite allergic patients has only been partly investigated.
Objective: To perform a detailed characterization of Der p 18 on a molecular, structural and immunological level.
Untreatable bacterial infections caused by a perpetual increase of antibiotic resistant strains represent a serious threat to human healthcare in the 21(st) century. Conjugative DNA transfer is the most important mechanism for antibiotic resistance and virulence gene dissemination among bacteria and is mediated by a protein complex, known as type IV secretion system (T4SS). The core of the T4SS is a multiprotein complex that spans the bacterial envelope as a channel for macromolecular secretion.
View Article and Find Full Text PDFConjugative transfer of DNA represents the most important transmission pathway in terms of antibiotic resistance and virulence gene dissemination among bacteria. TraH is a putative transfer protein of the type IV secretion system (T4SS) encoded by the Gram-positive (G+) conjugative plasmid pIP501. This molecular machine involves a multi-protein core complex spanning the bacterial envelope thereby serving as a macromolecular secretion channel.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
September 2014
Conjugative transfer through type IV secretion multiprotein complexes is the most important means of spreading antimicrobial resistance. Plasmid pIP501, frequently found in clinical Enterococcus faecalis and Enterococcus faecium isolates, is the first Gram-positive (G+) conjugative plasmid for which self-transfer to Gram-negative (G-) bacteria has been demonstrated. The pIP501-encoded type IV secretion system (T4SS) protein TraN localizes to the cytoplasm and shows specific DNA binding.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
April 2014
Conjugative plasmid transfer presents a serious threat to human health as the most important means of spreading antibiotic resistance and virulence genes among bacteria. The required direct cell-cell contact is established by a multi-protein complex, the conjugative type IV secretion system (T4SS). The conjugative core complex spans the cellular envelope and serves as a channel for macromolecular secretion.
View Article and Find Full Text PDFpIP501 is a conjugative broad-host-range plasmid frequently present in nosocomial Enterococcus faecalis and Enterococcus faecium isolates. We focus here on the functional analysis of the type IV secretion gene traG, which was found to be essential for pIP501 conjugative transfer between Gram-positive bacteria. The TraG protein, which localizes to the cell envelope of E.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
November 2012
Conjugative plasmid transfer is the most important route for the spread of resistance and virulence genes among bacteria. Consequently, bacteria carrying conjugative plasmids are a substantial threat to human health, especially hospitalized patients. Whilst detailed information about the process has been obtained for Gram-negative type-4 secretion systems, little is known about the corresponding mechanisms in Gram-positive (G+) bacteria.
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