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The viability of lithium-sulfur batteries as an energy storage technology depends on unlocking long-term cycle stability. Most instability stems from the release and transport of polysulfides from the cathode, which causes mossy growth on the lithium anode, leading to continuous consumption of electrolyte. Therefore, development of a durable cathode with minimal polysulfide escape is critical. Here, we present a saccharide-based binder system that has a capacity for the regulation of polysulfides due to its reducing properties. Furthermore, the binder promotes the formation of viscoelastic filaments during casting which endows the sulfur cathode with a desirable web-like microstructure. Taken together this leads to 97% sulfur utilisation with a cycle life of 1000 cycles (9 months) and capacity retention (around 700 mAh g −1 after 1000 cycles). A pouch cell prototype with a specific energy of up to 206 Wh kg −1 is produced, demonstrating the promising potential for practical applications. The long-term cycling of Li-S batteries depends on the polysulfides shuttling regulation. Here, the authors present a saccharide-based binder system to control the polysulfides migration and improve the cycle life of a Li-S pouch cell.

Omega-3 long-chain (≥C20) polyunsaturated fatty acids (ω3 LC-PUFA) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are critical for human health and development [corrected].. Numerous studies have indicated that deficiencies in these fatty acids can increase the risk or severity of cardiovascular, inflammatory and other diseases or disorders. EPA and DHA are predominantly sourced from marine fish although the primary producers are microalgae. Much work has been done to engineer a sustainable land-based source of EPA and DHA to reduce pressure on fish stocks in meeting future demand, with previous studies describing the production of fish oil-like levels of DHA in the model plant species, Arabidopsis thaliana. In this study we describe the production of fish oil-like levels (>12%) of DHA in the oilseed crop species Camelina sativa achieving a high ω3/ω6 ratio. The construct previously transformed in Arabidopsis as well as two modified construct versions designed to increase DHA production were used. DHA was found to be stable to at least the T5 generation and the EPA and DHA were found to be predominantly at the sn-1,3 positions of triacylglycerols. Transgenic and parental lines did not have different germination or seedling establishment rates. DHA can be produced at fish oil-like levels in industrially-relevant oilseed crop species using multi-gene construct designs which are stable over multiple generations. This study has implications for the future of sustainable EPA and DHA production from land-based sources.

Plant seeds have long been promoted as a production platform for novel fatty acids such as the ω3 long-chain (≥ C20) polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) commonly found in fish oil. In this article we describe the creation of a canola ( Brassica napus ) variety producing fish oil-like levels of DHA in the seed. This was achieved by the introduction of a microalgal/yeast transgenic pathway of seven consecutive enzymatic steps which converted the native substrate oleic acid to α-linolenic acid and, subsequently, to EPA, docosapentaenoic acid (DPA) and DHA. This paper describes construct design and evaluation, plant transformation, event selection, field testing in a wide range of environments, and oil profile stability of the transgenic seed. The stable, high-performing event NS-B50027-4 produced fish oil-like levels of DHA (9–11%) in open field trials of T3 to T7 generation plants in several locations in Australia and Canada. This study also describes the highest seed DHA levels reported thus far and is one of the first examples of a deregulated genetically modified crop with clear health benefits to the consumer.

Metalloenzymes preorganize the reaction environment to steer substrate(s) along the required reaction coordinate. Here, we show that phosphine ligands selectively facilitate protonation of binuclear silver hydride cations, [LAg 2 (H)] + by optimizing the geometry of the active site. This is a key step in the selective, catalysed extrusion of carbon dioxide from formic acid, HO 2 CH, with important applications (for example, hydrogen storage). Gas-phase ion-molecule reactions, collision-induced dissociation (CID), infrared and ultraviolet action spectroscopy and computational chemistry link structure to reactivity and mechanism. [Ag 2 (H)] + and [Ph 3 PAg 2 (H)] + react with formic acid yielding Lewis adducts, while [(Ph 3 P) 2 Ag 2 (H)] + is unreactive. Using bis(diphenylphosphino)methane (dppm) reshapes the geometry of the binuclear Ag 2 (H) + scaffold, triggering reactivity towards formic acid, to produce [dppmAg 2 (O 2 CH)] + and H 2 . Decarboxylation of [dppmAg 2 (O 2 CH)] + via CID regenerates [dppmAg 2 (H)] + . These gas-phase insights inspired variable temperature NMR studies that show CO 2 and H 2 production at 70 °C from solutions containing dppm, AgBF 4 , NaO 2 CH and HO 2 CH. Designing catalysts and understanding the influence of ligands for particular transformations remains a highly challenging task. Here, the authors show that bisphosphine ligands can alter the geometry of the active site in silver catalysts, driving protonation and ultimately extrusion of carbon dioxide from formic acid.

Amphotericin B (AmpB) is one of the oldest antifungal drugs in clinical use. It is an effective therapeutic, but it comes with toxicity issues due to the similarities between its fungal target (the membrane lipid ergosterol) and its mammalian counterpart (cholesterol). One strategy to improve its activity/toxicity relationship is by combinatorial therapy with potentiators, which would enable a lower therapeutic dose of AmpB. Here, we report on the discovery of the antibiotic gladiolin as a potentiator of AmpB against several priority human fungal pathogens and fungal biofilms, with no increased toxicity against mammalian cells. We show that gladiolin potentiates AmpB by increasing and accelerating membrane damage. Our findings also provide insights into the on-going debate about the mechanism of action of AmpB by indicating that both proposed mechanisms, extraction of ergosterol from membranes and pore formation, are potentiated by gladiolin.

The Labyrinthulomycetes or Labyrinthulea are a class of protists that produce a network of filaments that enable the cells to glide along and absorb nutrients. One of the main two Labyrinthulea groups is the thraustochytrids, which are becoming an increasingly recognised and commercially used alternate source of long-chain (LC, ≥C20) omega-3 containing oils. This study demonstrates, to our knowledge for the first time, the regiospecificity of the triacylglycerol (TAG) fraction derived from Australian thraustochytrid Aurantiochytrium sp. strain TC 20 obtained using 13C nuclear magnetic resonance spectroscopy (13C NMR) analysis. The DHA present in the TC 20 TAG fraction was determined to be concentrated in the sn-2 position, with TAG (16:0/22:6/16:0) identified as the main species present. The sn-2 preference is similar to that found in salmon and tuna oil, and differs to seal oil containing largely sn-1,3 LC-PUFA. A higher concentration of sn-2 DHA occurred in the thraustochytrid TC 20 oil compared to that of tuna oil.

Fullerenes are a class of carbon nanomaterials that find a wide range of applications in biomedical fields, especially for photodynamic cancer therapy because of its photosensitive effect. However, hydrophobic fullerenes can only be dispersed in organic solvents which hinders their biomedical applications. Here, we report a facile method to prepare highly water‐dispersible fullerene (C60)‐polymer nanoparticles with hydrodynamic sizes of 50–70 nm. Hydrophilic random copolymers containing different ratios of polyethylene glycol methyl ether methacrylate and 2‐aminoethylmethacrylamide were synthesized for conjugating with C60 molecules through efficient nucleophilic Michael addition reaction between amine groups from hydrophilic polymer and carbon‐carbon double bonds from C60. As a result, the amphiphilic C60‐polymer conjugates could be well dispersed and nano‐assembled in water with a C60 concentration as high as 7.8 mg/mL, demonstrating a significant improvement for the solubility of C60 in an aqueous system. Owing to the high C60 content, the C60‐polymer nanoparticles showed a strong photodynamic therapy effect on human lung cancer cells (A549) under light irradiation (450 nm) in both 2D cell culture and 3D spheroid culture, while demonstrating ignorable cytotoxicity under dark. This highly efficient and convenient method to prepare water‐dispersible C60‐polymer conjugates may have a great impact on the future biomedical applications of fullerenes. This work used controlled living free radical polymerization (reversible addition‐fragmentation chain transfer) to prepare copolymers of precise compositions. The conjugation method of C60 molecules with polymers is more efficient and simpler to generate highly water‐dispersible nanoparticles compared to literature methods. In addition, the C60 concentration of this work is much higher than literature reported, yet the stability of nanoparticle aqueous solution is superior, which can be stored at room temperature for more than 1 year without aggregation. Such highly aqueously stable C60 nanoparticles showed non‐cytotoxicity under dark conditions but high photo‐cytotoxicity with light irradiation (visible light, short time and low intensity), which can lead to targeted killing of cancer cells.

Metabolic engineering of the omega-3 (ω3) long chain polyunsaturated fatty acid biosynthesis pathway has generated fish oil-like levels of pharmaceutically and nutritionally important docosahexaenoic acid (DHA) in plant seeds. However, the majority of DHA has been accumulated at the -1 and -3 positions of triacylglycerol (TAG) in these engineered seeds, leaving only a minor amount (∼10%) at -2 position and indicating a strong discrimination (or, a very poor specificity) for DHA by seed lysophosphatidic acid acyltransferases (LPAATs), which mediate the acylation of -2 position of glycerol backbone. In order to increase the level of DHA at -2 position of TAG and to increase overall DHA level in seeds, we attempted to discover DHA-preferring LPAATs. Several LPAATs for acylation of the -2 position of the TAG glycerol backbone were investigated for substrate preference for DHA. In transiently expressing these LPAATs in , a LPAAT had the highest substrate specificity for accumulating DHA onto oleoyl-lysophosphatidic acid (oleoyl-LPA), while the plant LPAATs tested showed lower preference for DHA. In a competition assay with a pool of four ω3 acyl-Coenzyme A (CoA) substrates involved in the DHA biosynthesis pathway, LPAATs from both and showed a high preference for DHA-CoA acylation onto oleoyl-LPA. When docosahexaenoyl-LPA was used as the acyl receiver, LPAAT also showed a high preference for DHA-CoA. Stable overexpression of LPAAT in an Arabidopsis line that expressed the DHA biosynthesis pathway significantly increased both the total DHA levels and the distribution of DHA onto the -2 position of seed TAG. LC-MS analysis of the seed TAG species also confirmed that overexpression of LPAAT increased di-DHA and tri-DHA TAGs, suggesting that the LPAAT could enrich DHA at the TAG -2 position, leading to a metabolic engineering of oil seed for channeling DHA into the -2 position of TAG and to a higher DHA level.

Residues within processed protein fragments bound to major histocompatibility complex class I (MHC-I) glycoproteins have been considered to function as a series of \"independent pegs\" that either anchor the peptide (p) to the MHC-I and/or interact with the spectrum of αβ-T-cell receptors (TCRs) specific for the pMHC-I epitope in question. Mining of the extensive pMHC-I structural database established that many self- and viral peptides show extensive and direct interresidue interactions, an unexpected finding that has led us to the idea of \"constrained\" peptides. Mutational analysis of two constrained peptides (the HLA B44 restricted self-peptide (B44DPα-EEFGRAFSF) and an H2-Db restricted influenza peptide (DbPA, SSLENFRAYV) demonstrated that the conformation of the prominently exposed arginine in both peptides was governed by interactions with MHC-I-orientated flanking residues from the peptide itself. Using reverse genetics in a murine influenza model, we revealed that mutation of an MHC-I-orientated residue (SSLENFRAYV [rightward arrow] SSLENARAYV) within the constrained PA peptide resulted in a diminished cytotoxic T lymphocyte (CTL) response and the recruitment of a limited pMHC-I specific TCR repertoire. Interactions between individual peptide positions can thus impose fine control on the conformation of pMHC-I epitopes, whereas the perturbation of such constraints can lead to a previously unappreciated mechanism of viral escape.

The ongoing use of chemical warfare agents (CWAs) in conflicts, assassinations, and terrorist attacks means that the detection and identification of these compounds are crucial. The forensic identification of organophosphorus nerve agents (OPNAs) and their precursors and degradation products remains challenging due to the destructive nature and extensive preparation required for conventional chromatographic methods. In this study, we characterise precursor and degradation products of Novichok analogues, including 1,1,3,3-tetramethylguanidine, N,N-diethylpentanimidamide, N,N-dipropylbutanimidamide, using 2D ¹H–¹³C heteronuclear multiple quantum coherence (HMQC) NMR. We further investigate mixtures of phosphonate compounds [dimethyl methylphosphonate (DMMP), diisopropyl methylphosphonate (DIMP), diethyl 2,2-diethoxyethylphosphonate (DEOP), and dibutyl butylphosphonate (DBBP)] and a fully degraded VX sample using ¹H diffusion-ordered spectroscopy (DOSY) and 3D ¹H–¹³C DOSY-HMQC NMR. The ¹H DOSY experiments successfully separated components of both amine and phosphonate mixtures, while analysis of the degraded VX sample revealed key degradation products, including ethyl methylphosphonic acid and bis-2-(diisopropylaminoethyl)disulfide. The 3D DOSY-HMQC method provided improved resolution of overlapping signals compared to 2D approaches, representing the first application of this experiment to CWA-related compounds. These results demonstrate that DOSY-based NMR can virtually separate complex mixtures non-destructively, providing complementary capability to GC-MS and LC-MS in forensic CWA investigations. •First use of 3D ¹H‐¹³C DOSY-HMQC NMR for CWA-related compound analysis.•Amidines linked to Novichok analogues characterized using 2D NMR.•DOSY NMR shown to complement GC and LC techniques in forensic CWA investigations.