Adjuvant strategies to tackle -mediated polymyxin resistance.

The emergence of the () gene is a demonstrable threat contributing to the worldwide antibiotic resistance crisis. The gene is encoded on plasmids and can easily spread between different bacterial strains. encodes a phosphoethanolamine (pEtN) transferase, which catalyses the transfer of the pEtN moiety from phosphatidylethanolamine to lipid A, the head group of lipopolysaccharides (LPS).

IL-9 sensitizes human T2 cells to proinflammatory IL-18 signals in atopic dermatitis.

Background: T2 cells crucially contribute to the pathogenesis of atopic dermatitis (AD) by secreting high levels of IL-13 and IL-22. Yet the upstream regulators that activate T2 cells in AD skin remain unclear. IL-18 is a putative upstream regulator of T2 cells because it is implicated in AD pathogenesis and has the capacity to activate T cells.

Host-Guest Interactions Facilitated by Chalcogen Bonding within Selenadiazole Functionalised Porphyrin Nanotubes.

The structural rigidity of tetrakis(4-pyridyl)porphyrin (TPyP) has been utilised to prepare a robust novel porous coordination polymer of composition Cd(TPyP)(sez) (TPyP=5,10,15,20-tetra(4-pyridyl)porphyrin, sez=1,2,5-benzoselenadiazole-5-carboxylate). The coordination polymer may be described as a hexagonal porphyrin nanotube (PNT) and has the potential to bind guest molecules through chalcogen bonding. Single crystal X-ray diffraction (SCXRD) data indicate an internal pore diameter ~9 Å which represents ~35 % of the crystal volume.

Combined inhibition of histone methyltransferases EZH2 and DOT1L is an effective therapy for neuroblastoma.

Background: The child cancer, neuroblastoma (NB), is characterised by a low incidence of mutations and strong oncogenic embryonal driver signals. Many new targeted epigenetic modifier drugs have failed in human trials as monotherapy.

Methods: We performed a high-throughput, combination chromatin-modifier drug screen against NB cells.

Expanding the Library of Covalent Cysteine Cathepsin Probes Featuring Sulfoxonium Ylide Electrophiles.

Covalent activity-based probes are invaluable tools to monitor protease activity in vitro and in vivo. We recently discovered that dimethyl sulfoxonium ylides (SYs) bind selectively to cysteine cathepsin proteases in a mechanism-dependent manner. Herein, we present the synthetic routes and characterization of an expanded library of SY probes with a greater diversity in recognition sequences.

Generating mammalian knock-out cell lines to investigate mitochondrial protein complex assembly.

The development of easy-to-use gene-editing approaches has revolutionized the study of mitochondrial protein complex assembly in mammalian cells. Once the domain of classical cell biology models such Saccharomyces cerevisiae, human knockout cell lines lacking expression of a specific protein can be made at low cost and in as little as two to three weeks. In this chapter we outline our approach to generation of knockouts in commonly used transformed laboratory cell lines, with a view toward their use in the study of mitochondrial respiratory chain complex assembly and mitochondrial biology.

Structural and biophysical characterisation of ubiquitin variants that inhibit the ubiquitin conjugating enzyme Ube2d2.

The ubiquitin-conjugating E2 enzymes play a central role in ubiquitin transfer. Disruptions to the ubiquitin system are implicated in multiple diseases, and as a result, molecules that modulate the activity of the ubiquitin system are of interest. E2 enzyme function relies on interactions with partner proteins, and the disruption of these is an effective way to modulate activity.

The structure of the IL-11 signalling complex provides insight into receptor variants associated with craniosynostosis.

Interleukin 11 (IL-11), a member of the IL-6 family of cytokines, has roles in haematopoiesis, inflammation, bone metabolism, and craniofacial development. IL-11 also has pathological roles in chronic inflammatory diseases, fibrosis, and cancer. In this structural snapshot, we explore our recently published cryo-EM structure of the human IL-11 signalling complex to understand the molecular mechanisms of complex formation and disease-associated mutations.

Monitoring the in vitro import and assembly of mitochondrial precursor proteins into mammalian mitochondria.

Mitochondrial protein import is a complex process governing the delivery of the organelle's proteome. This process, in turn, is essential for maintaining mitochondrial function and cellular homeostasis. Initiated by protein synthesis in the cytoplasm, precursor proteins destined for the mitochondria possess targeting signals that guide them to the mitochondrial surface.

Rifaximin prophylaxis causes resistance to the last-resort antibiotic daptomycin.

Multidrug-resistant bacterial pathogens like vancomycin-resistant Enterococcus faecium (VREfm) are a critical threat to human health. Daptomycin is a last-resort antibiotic for VREfm infections with a novel mode of action, but for which resistance has been widely reported but is unexplained. Here we show that rifaximin, an unrelated antibiotic used prophylactically to prevent hepatic encephalopathy in patients with liver disease, causes cross-resistance to daptomycin in VREfm.

Shear-Sensing by C-Reactive Protein: Linking Aortic Stenosis and Inflammation.

Background: CRP (C-reactive protein) is a prototypical acute phase reactant. Upon dissociation of the pentameric isoform (pCRP [pentameric CRP]) into its monomeric subunits (mCRP [monomeric CRP]), it exhibits prothrombotic and proinflammatory activity. Pathophysiological shear rates as observed in aortic valve stenosis (AS) can influence protein conformation and function as observed with vWF (von Willebrand factor).

An integrated multi-omics approach allowed ultra-rapid diagnosis of a deep intronic pathogenic variant in PDHX and precision treatment in a neonate critically ill with lactic acidosis.

The diagnosis of mitochondrial disorders is complex. Rapid whole genome sequencing is a first line test for critically ill neonates and infants allowing rapid diagnosis and treatment. Standard genomic technology and bioinformatic pipelines still have an incomplete diagnostic yield requiring complementary approaches.

Direct recognition of an intact foreign protein by an αβ T cell receptor.

αβ T cell receptors (αβTCRs) co-recognise antigens when bound to Major Histocompatibility Complex (MHC) or MHC class I-like molecules. Additionally, some αβTCRs can bind non-MHC molecules, but how much intact antigen reactivities are achieved remains unknown. Here, we identify an αβ T cell clone that directly recognises the intact foreign protein, R-phycoerythrin (PE), a multimeric (αβ)γ protein complex.

On the function of TRAP substrate-binding proteins: Conformational variation of the sialic acid binding protein SiaP.

Tripartite ATP-independent periplasmic (TRAP) transporters are analogous to ABC transporters in that they use a substrate-binding protein to scavenge metabolites (e.g., N-acetylneuraminate) and deliver them to the membrane components for import.

Membrane association and polar localization of the T4SS DotO ATPase mediated by two nonredundant receptors.

The Dot/Icm type IVB secretion system (T4BSS) is a large, multisubunit complex that exports a vast array of substrates into eukaryotic host cells. DotO, a distant homolog of the T4ASS ATPase VirB4, associates with the bacterial inner membrane despite lacking hydrophobic transmembrane domains. Employing a genetic approach, we found DotO's membrane association is mediated by three inner-membrane Dot/Icm components, IcmT, and a combined DotJ-DotI complex (referred to as DotJI).

Crystal structure of Alzheimer's disease phospholipase D3 provides a molecular basis for understanding its normal and pathological functions.

Human 5'-3' exonuclease PLD3, a member of the phospholipase D family of enzymes, has been validated as a therapeutic target for treating Alzheimer's disease. Here, we have determined the crystal structure of the luminal domain of the enzyme at 2.3 Å resolution, revealing a bilobal structure with a catalytic site located between the lobes.

Advances in the cell biology of the trafficking and processing of amyloid precursor protein: impact of familial Alzheimer's disease mutations.

The production of neurotoxic amyloid-β peptides (Aβ) is central to the initiation and progression of Alzheimer's disease (AD) and involves sequential cleavage of the amyloid precursor protein (APP) by β- and γ-secretases. APP and the secretases are transmembrane proteins and their co-localisation in the same membrane-bound sub-compartment is necessary for APP cleavage. The intracellular trafficking of APP and the β-secretase, BACE1, is critical in regulating APP processing and Aβ production and has been studied in several cellular systems.

Blood Distribution of SARS-CoV-2 Lipid Nanoparticle mRNA Vaccine in Humans.

Lipid nanoparticle mRNA vaccines are an exciting but emerging technology used in humans. There is limited understanding of the factors that influence their biodistribution and immunogenicity. Antibodies to poly(ethylene glycol) (PEG), which is on the surface of the lipid nanoparticle, are detectable in humans and boosted by human mRNA vaccination.