Proc Natl Acad Sci U S A
November 2024
Pdr5 is the most abundant ABC transporter in Saccharomyces cerevisiae and plays a major role in the pleiotropic drug resistance (PDR) network, which actively prevents cell entry of a large number of structurally unrelated compounds. Due to a high level of asymmetry in one of its nucleotide binding sites (NBS), Pdr5 serves as a perfect model system for asymmetric ABC transporter such as its medical relevant homologue Cdr1 from Candida albicans. In the past 30 years, this ABC transporter was intensively studied in vivo and in plasma membrane vesicles.
View Article and Find Full Text PDFTo enter epithelial cells, the obligate intracellular pathogen Chlamydia pneumoniae secretes early effector proteins, which bind to and modulate the host-cell's plasma membrane and recruit several pivotal endocytic host proteins. Here, we present the high-resolution structure of an entry-related chlamydial effector protein, SemD. Co-crystallisation of SemD with its host binding partners demonstrates that SemD co-opts the Cdc42 binding site to activate the actin cytoskeleton regulator N-WASP, making active, GTP-bound Cdc42 superfluous.
View Article and Find Full Text PDFToxoplasma gondii is a widely distributed apicomplexan parasite causing toxoplasmosis, a critical health issue for immunocompromised individuals and for congenitally infected foetuses. Current treatment options are limited in number and associated with severe side effects. Thus, novel anti-toxoplasma agents need to be identified and developed.
View Article and Find Full Text PDFIntroduction: The impact of multiple health conditions on bowel cancer screening is currently unknown. We explored the impact of multiple health conditions on bowel cancer screening perceptions, experience and clinical management decisions following a positive stool test.
Methods: Semi-structured qualitative interviews were conducted remotely with Bowel Screening Wales staff (n = 16) stratified by regional location and role and with screening participants (n = 19) stratified by age, gender and comorbidity.
Background: Factor (F)XII triggers contact activation by binding to foreign surfaces, with the epidermal growth factor-like 1 (EGF-1) domain being the primary binding site. Blocking FXII surface-binding might hold therapeutic value to prevent medical device-induced thrombosis.
Objectives: To unravel and prevent EGF-1-mediated FXII surface-binding with a variable domain of heavy chain-only antibody (VH).
Background: UK cancer mortality is worse than in many other high-income countries, partly because of diagnostic delays in primary care.
Aim: To understand beliefs and behaviours of GPs, and systems of general practice teams, to inform the Think Cancer! intervention development.
Design And Setting: An embedded qualitative study guided by behaviour change models (COM-B [Capability, Opportunity, Motivation - Behaviour] and theoretical domains framework [TDF]) in primary care in Wales, UK.
Type I secretion systems (T1SS) facilitate the secretion of substrates in one step across both membranes of Gram-negative bacteria. A prime example is the hemolysin T1SS which secretes the toxin HlyA. Secretion is energized by the ABC transporter HlyB, which forms a complex together with the membrane fusion protein HlyD and the outer membrane protein TolC.
View Article and Find Full Text PDFvon Willebrand factor (VWF) is an essential contributor to microvascular thrombosis. Physiological cleavage by ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) limits its prothrombotic properties, explaining why ADAMTS13 deficiency leads to attacks of microthrombosis in patients with thrombotic thrombocytopenic purpura (TTP). We previously reported that plasminogen activation takes place during TTP attacks in these patients.
View Article and Find Full Text PDFClinically used pan and class I HDACi cause severe side effects, whereas class IIa HDACi are less cytotoxic. Here, we present the synthesis and anticancer effects of a series of 5-(trifluoromethyl)-1,2,4-oxadiazole (TFMO)-based amides and alkoxyamides derived from the previously reported class IIa HDACi YAK540. The most active class IIa inhibitor 1a showed nanomolar inhibition of the class IIa enzymes 4, 5, 7 (IC HDAC4: 12 nM) and high selectivity (selectivity index >318 for HDAC4) over non-class IIa HDACs.
View Article and Find Full Text PDFGuanylate-binding proteins (GBPs) are essential interferon-γ-activated large GTPases that play a crucial role in host defense against intracellular bacteria and parasites. While their protective functions rely on protein polymerization, our understanding of the structural intricacies of these multimerized states remains limited. To bridge this knowledge gap, we present dimer models for human GBP1 (hGBP1) and murine GBP2 and 7 (mGBP2 and mGBP7) using an integrative approach, incorporating the crystal structure of hGBP1's GTPase domain dimer, crosslinking mass spectrometry, small-angle X-ray scattering, protein-protein docking, and molecular dynamics simulations.
View Article and Find Full Text PDFThe nasal and bronchial epithelium are unified parts of the respiratory tract that are affected in the monogenic disorder cystic fibrosis (CF). Recent studies have uncovered that nasal and bronchial tissues exhibit intrinsic variability, including differences in mucociliary cell composition and expression of unique transcriptional regulatory proteins which relate to germ layer origin. In the present study, we explored whether intrinsic differences between nasal and bronchial epithelial cells persist in cell cultures and affect epithelial cell functioning in CF.
View Article and Find Full Text PDFBiochim Biophys Acta Proteins Proteom
January 2024
CBL1 is an EF hand Ca binding protein from A. thaliana that is involved in the detection of cellular Ca signals and the downstream signal transmission by interaction with the protein kinase CIPK23. So far, the structure and calcium ion binding affinities of CBL1 remain elusive.
View Article and Find Full Text PDFSynthetic cytokine receptors can modulate cellular functions based on an artificial ligand to avoid off-target and/or unspecific effects. However, ligands that can modulate receptor activity so far have not been used clinically because of unknown toxicity and immunity against the ligands. Here, we developed a fully synthetic cytokine/cytokine receptor pair based on the antigen-binding domain of the respiratory syncytial virus-approved mAb Palivizumab as a synthetic cytokine and a set of anti-idiotype nanobodies (AIP) as synthetic receptors.
View Article and Find Full Text PDFPolyethylene terephthalate (PET) is a commodity polymer known to globally contaminate marine and terrestrial environments. Today, around 80 bacterial and fungal PET-active enzymes (PETases) are known, originating from four bacterial and two fungal phyla. In contrast, no archaeal enzyme had been identified to degrade PET.
View Article and Find Full Text PDFBackground: A quasi-experimental study investigated a pharmacist-led intervention aimed at deprescribing and medication management among adult patients with type 2 diabetes at risk of hypoglycaemia.
Objective: This study aimed to evaluate the process of implementing the intervention consisting of a tailored clinical medication review (CMR) supported by a training and a toolbox.
Methods: Mixed-methods study based on the Grant framework, including the domains "recruitment," "delivery of intervention" and "response" of pharmacists and patients.
Polyethylene terephthalate (PET) is a widely used synthetic polymer and known to contaminate marine and terrestrial ecosystems. Only few PET-active microorganisms and enzymes (PETases) are currently known, and it is debated whether degradation activity for PET originates from promiscuous enzymes with broad substrate spectra that primarily act on natural polymers or other bulky substrates, or whether microorganisms evolved their genetic makeup to accepting PET as a carbon source. Here, we present a predicted diene lactone hydrolase designated PET40, which acts on a broad spectrum of substrates, including PET.
View Article and Find Full Text PDFThe plant hormone receptor ETR1 regulates many highly relevant agronomic processes. Today, significant functional and structural questions remain unanswered regarding its multi-pass transmembrane sensor domain able to bind and respond to the gaseous plant hormone ethylene at femtomolar concentrations. A significant reason for this is the lack of structural data on full-length ETR1 in a lipid environment.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
August 2023
Secretion of proteins into the extracellular space has great advantages for the production of recombinant proteins. Type 1 secretion systems (T1SS) are attractive candidates to be optimized for biotechnological applications, as they have a relatively simple architecture compared to other classes of secretion systems. A paradigm of T1SS is the hemolysin A type 1 secretion system (HlyA T1SS) from Escherichia coli harboring only three membrane proteins, which makes the plasmid-based expression of the system easy.
View Article and Find Full Text PDFThe chromatophores in are evolutionary-early-stage photosynthetic organelles. Biological processes in chromatophores depend on a combination of chromatophore and nucleus-encoded proteins. Interestingly, besides proteins carrying chromatophore-targeting signals, a large arsenal of short chromatophore-targeted proteins (sCTPs; <90 amino acids) without recognizable targeting signals were found in chromatophores.
View Article and Find Full Text PDFWe present a protocol to generate organoids from air-liquid-interface (ALI)-differentiated nasal epithelia. We detail their application as cystic fibrosis (CF) disease model in the cystic fibrosis transmembrane conductance regulator (CFTR)-dependent forskolin-induced swelling (FIS) assay. We describe steps for isolation, expansion and cryostorage of nasal brushing-derived basal progenitor cells, and their differentiation in ALI cultures.
View Article and Find Full Text PDFCopy number alterations (CNA) are powerful prognostic markers in myelodysplastic neoplasms (MDS) and are routinely analyzed by conventional cytogenetic analysis (CCA) on bone marrow (BM). Although CCA is still the gold standard, it requires extensive hands-on time and highly trained staff for the analysis, making it a laborious technique. To reduce turn-around-time per case, shallow whole genome sequencing (sWGS) technologies offer new perspectives for the diagnostic work-up of this disorder.
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