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Viral replication often depends on RNA maturation and degradation processes catalyzed by viral ribonucleases, which are therefore candidate targets for antiviral drugs. Here, we synthesized and studied the antiviral properties of a novel nitrocatechol compound (1c) and other analogs that are structurally related to the catechol derivative dynasore. Interestingly, compound 1c strongly inhibited two DEDD box viral ribonucleases, HIV-1 RNase H and SARS-CoV-2 nsp14 3′-to-5′ exoribonuclease (ExoN). While 1c inhibited SARS-CoV-2 ExoN activity, it did not interfere with the mRNA methyltransferase activity of nsp14. In silico molecular docking placed compound 1c in the catalytic pocket of the ExoN domain of nsp14. Finally, 1c inhibited SARS-CoV-2 replication but had no toxicity to human lung adenocarcinoma cells. Given its simple chemical synthesis from easily available starting materials, these results suggest that 1c might be a lead compound for the design of new antiviral compounds that target coronavirus nsp14 ExoN and other viral ribonucleases. [ABSTRACT FROM AUTHOR]

The fibronectin type II (FnII) domain, present in diverse vertebrate proteins, plays crucial roles in several fundamental biological processes. PDC‐109, the major bovine seminal plasma protein, contains two FnII domains that bind to choline phospholipids on sperm plasma membrane and induce lipid efflux crucial for successful fertilization. PDC‐109 also exhibits chaperone‐like activity and protects other proteins against various types of stress. Here, we show that a core tryptophan residue is highly conserved across species in the FnII domains. Mutation of conserved tryptophan residues W47, W93, and W106 in the FnII domains of PDC‐109 to alanine leads to drastic decrease or complete abolition of membrane‐binding and chaperone‐like activities. These observations suggest that conserved tryptophans are important for the function of FnII proteins. [ABSTRACT FROM AUTHOR]

The paradigm of the organisation as service provider dominates current research. Most work focuses on the adoption of services by product-centred organisations, promoting the concept of a service continuum. This paper explores whether alternatives are possible, documenting a case study which apparently ‘reverses' this continuum – a service-based SME which has developed in-house manufacturing capability to improve the customer solution. The findings suggest that this could develop the current understanding of servitisation, however further work is outlined to test this. [ABSTRACT FROM AUTHOR]

Abstract: Aberrant copper homeostasis and oxidative stress have critical roles in several neurodegenerative diseases. Expression of heat-shock protein 27 (Hsp27) is elevated under oxidative stress as well as upon treatment with Cu2+, and elevated levels of Hsp27 are found in the brains of patients with Alzheimer and Parkinson diseases. We demonstrate, using steady-state and time-resolved fluorescence spectroscopy as well as isothermal titration calorimetry studies, that Hsp27 binds Cu2+ with high affinity (K d ~10?11 M). Treating IMR-32 human neuroblastoma cells with Cu2+ leads to upregulation of endogenous Hsp27. Further, overexpression of Hsp27 in IMR-32 human neuroblastoma cells confers cytoprotection against Cu2+-induced cell death. Hsp27 prevents the deleterious interaction of Cu2+ with ?-synuclein, the protein involved in Parkinson disease and synucleinopathies. Hsp27 attenuates Cu2+- or Cu2+–?-synuclein-mediated generation of reactive oxygen species and confers cytoprotection on IMR-32 cells as well as on mouse primary neural precursor cells. Hsp27 prevents Cu2+–ascorbate or Cu2+–?-synuclein–ascorbate treatment-induced increase in mitochondrial superoxide level and mitochondrial disorganization in IMR-32 cells. Hsp27 dislodges the ?-synuclein-bound Cu2+ and prevents the Cu2+-mediated amyloidogenesis of ?-synuclein. Our findings that Hsp27 binds Cu2+ with high affinity leading to beneficial effects and that Hsp27 can dislodge Cu2+ from ?-synuclein, preventing amyloid fibril formation, indicate potential therapeutic strategies for neurodegenerative diseases involving aberrant Cu2+ homeostasis. [Copyright &y& Elsevier]

Severe acute respiratory syndrome coronavirus (SARS-CoV)-2 has caused millions of deaths since its emergence in 2019. Innate immune antagonism by lethal CoVs such as SARS-CoV-2 is crucial for optimal replication and pathogenesis. The conserved nonstructural protein 15 (nsp15) endoribonuclease (EndoU) limits activation of double-stranded (ds)RNA-induced pathways, including interferon (IFN) signaling, protein kinase R (PKR), and oligoadenylate synthetase/ribonuclease L (OAS/RNase L) during diverse CoV infections including murine coronavirus and Middle East respiratory syndrome (MERS)-CoV. To determine how nsp15 functions during SARS-CoV-2 infection, we constructed a recombinant SARS-CoV-2 (nsp15mut) expressing catalytically inactivated nsp15, which we show promoted increased dsRNA accumulation. Infection with SARS-CoV-2 nsp15mut led to increased activation of the IFN signaling and PKR pathways in lung-derived epithelial cell lines and primary nasal epithelial air-liquid interface (ALI) cultures as well as significant attenuation of replication in ALI cultures compared to wild-type virus. This replication defect was rescued when IFN signaling was inhibited with the Janus activated kinase (JAK) inhibitor ruxolitinib. Finally, to assess nsp15 function in the context of minimal (MERS-CoV) or moderate (SARS-CoV-2) innate immune induction, we compared infections with SARS-CoV-2 nsp15mut and previously described MERS-CoV nsp15 mutants. Inactivation of nsp15 had a more dramatic impact on MERS-CoV replication than SARS-CoV-2 in both Calu3 cells and nasal ALI cultures suggesting that SARS-CoV-2 can better tolerate innate immune responses. Taken together, SARS-CoV-2 nsp15 is a potent inhibitor of dsRNA-induced innate immune response and its antagonism of IFN signaling is necessary for optimal viral replication in primary nasal ALI cultures. [ABSTRACT FROM AUTHOR]

The food manufacturing sector is one of the most dominant consumers of energy across the globe. Food processing methods such as drying, baking, frying, malting, roasting, etc. rely heavily on the heat released from burning fossil fuels, mainly natural gas or propane. Less than half of this heat contributes to the actual processing of the product and the remaining is released to the surroundings as waste heat, primarily through exhaust gases at 150 to 250 °C. Recovering this waste heat can deliver significant fuel, cost and CO2 savings. However, selecting an appropriate sink for this waste heat is challenging due to the relatively low source temperature. This study investigates a novel application of gas-to-air low temperature waste heat recovery technology for a confectionary manufacturing process, through a range of experiments. The recovered heat is used to preheat a baking oven's combustion air at inlet before it enters the fuel-air mixture. The investigated technology is compared with other waste heat recovery schemes involving Regenerative Organic Rankine Cycles (RORC), Vapour Absorption Refrigeration (VAR) and hot water production. The findings indicate that utilising an oven's exhaust gases to preheat combustion air can deliver up to 33% fuel savings, provided a sufficiently large heat sink in the form of oven combustion air is available. Due to a lower investment cost, the technology also offers a payback period of only 1.57 years, which makes it financially attractive when compared to others. The studied waste heat recovery technologies can deliver a CO2 savings of 28–356 tonnes per year from a single manufacturing site. The modelling and comparison methodology, observations and outcomes of this study can be extended to a variety of low temperature food manufacturing processes. [ABSTRACT FROM AUTHOR]

A new polarizable water model is developed for molecular dynamics (MD) simulations of the proton transport process. The interatomic potential model has three important submodels corresponding to electrostatic interactions, making and breaking of covalent bonds, and treatment of electron exchange and correlation through a van der Waals potential. A polarizable diffuse charge density function was used to describe Coulombic interactions between atoms. Most of the model parameters were obtained from ab initio data for a lone water molecule. Molecules respond realistically to their electrochemical environment by the use of coupled fluctuating charge and fluctuating dipole dynamics, which controlled the charge density. The main purpose of the work is to develop a general model and framework for future studies, though some validation work was performed here. We applied the model to a MD simulation study of bulk properties of liquid water at room temperature and model gave good agreement with thermodynamic and transport properties at the same conditions. The model was then applied to a preliminary study of proton transfer, in which multiple proton transfer events were observed, though the rate of proton transfer was under-predicted by a factor of 5. [ABSTRACT FROM AUTHOR]

Abstract The major bovine seminal plasma protein, PDC-109, is a mixture of glycosylated (BSP-A1) and non-glycosylated (BSP-A2) isoforms of a 109-residue long polypeptide. It binds to spermatozoa by specifically recognizing choline phospholipids on the plasma membrane and destabilizes it by penetrating the hydrophobic interior, resulting in lipid efflux, which is necessary for sperm capacitation and successful fertilization. PDC-109 also acts as a molecular chaperone and protects target proteins from denaturation and aggregation induced by various types of stress. In order to investigate the role of glycosylation in these activities, we have separated BSP-A1 and BSP-A2 from PDC-109, and also cloned and expressed BSP-A2 in E. coli and purified the recombinant BSP-A2 (rBSP-A2) to homogeneity. Employing biophysical and biochemical approaches we have investigated the membrane-perturbing and chaperone-like activities (CLA) of PDC-109, BSP-A1, BSP-A2 and recombinant BSP-A2 (rBSP-A2). The results obtained demonstrate that glycan-lacking wild-type BSP-A2 and rBSP-A2 exhibit higher membrane-perturbing activity but decreased CLA as compared to PDC-109. In contrast, BSP-A1 exhibits significantly higher CLA than PDC-109, but its ability to destabilize membranes is considerably lower. This differential modulation of the membrane-perturbing and chaperone-like activities has been explained on the basis of higher membrane-penetrating ability and lower solubility of glycan-lacking BSP-A2 as compared to the glycosylated BSP-A1. Graphical abstract Image 1 Highlights • PDC-109, a bovine seminal plasma protein, is necessary for successful fertilization. • It is a mixture of glycosylated (BSP-A1) and non-glycosylated (BSP-A2) isoforms. • PDC-109 induces membrane lysis and exhibits chaperone-like activity (CLA). • We investigated the role of glycosylation in the membrane lysis and CLA of PDC-109. • Glycosylation decreases the membranolytic activity of PDC-109 but increases its CLA. [ABSTRACT FROM AUTHOR]

A direct correlation between brain iron and Alzheimer's disease (AD) raises questions regarding the transport of non-transferrin-bound iron (NTBI), a toxic but less researched pool of circulating iron that is likely to increase due to pathological and/or iatrogenic systemic iron overload. Here, we compared the distribution of radiolabeled-NTBI (59Fe-NTBI) and transferrin-bound iron (59Fe-Tf) in mouse models of iron overload in the absence or presence of inflammation. Following a short pulse, most of the 59Fe-NTBI was taken up by the liver, followed by the kidney, pancreas, and heart. Notably, a strong signal of 59Fe-NTBI was detected in the brain ventricular system after 2 h, and the brain parenchyma after 24 h. 59Fe-Tf accumulated mainly in the femur and spleen, and was transported to the brain at a much slower rate than 59Fe-NTBI. In the kidney, 59Fe-NTBI was detected in the cortex after 2 h, and outer medulla after 24 hours. Most of the 59Fe-NTBI and 59Fe-Tf from the kidney was reabsorbed; negligible amount was excreted in the urine. Acute inflammation increased the uptake of 59Fe-NTBI by the kidney and brain from 2-24 hours. Chronic inflammation, on the other hand, resulted in sequestration of iron in the liver and kidney, reducing its transport to the brain. These observations provide direct evidence for the transport of NTBI to the brain, and reveal a complex interplay between inflammation and brain iron homeostasis. Further studies are necessary to determine whether transient increase in NTBI due to systemic iron overload is a risk factor for AD. [ABSTRACT FROM AUTHOR]