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Lancet Planet Health. 2027 Mar 3:101445. doi: 10.1016/j.lanplh.2026.101445. Online ahead of print.

ABSTRACT

BACKGROUND: Antimicrobial resistance (AMR) emerges primarily through antibiotic exposure and the resulting selection pressure, but climate change is likely to accelerate the dissemination of AMR, particularly for zoonotic diseases, such as those caused by Salmonella. However, the link between climatic factors and antimicrobial resistance genes (ARGs) carried by Salmonella remains poorly characterised. This longitudinal ecological study aimed to link climate change to ARGs using multiple regression models.

METHODS: We analysed a comprehensive dataset of 488 232 Salmonella genomes and multiple potential predictors from 139 countries or regions over the period 1940-2023. Robustness was verified via Tobit and generalised additive models. Climate-related changes of average ARG abundance in Salmonella were quantified through counterfactual scenarios. Future ARG trends were projected to 2100 using integrated Shared Socioeconomic Pathways (SSPs) with Representative Concentration Pathways scenarios (SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5).

FINDINGS: The global average ARG abundance in Salmonella has increased by 38% (0·50 copies per cell) in the time period considered. Multiple regression models revealed that variability in ARGs follows a non-linear quadratic response to temperature and precipitation. Climate change is associated with a 10% (95% CI 5·4-13·3) global rise in the abundance of Salmonella ARGs, with increases observed in 82 (82%) of 100 countries. By 2100, the emergence of ARGs is projected to be further intensified by warming; however, achieving low-emission (SSP1-2.6) targets alongside strengthened antibiotic stewardship programmes could reduce Salmonella ARGs by 24% (95% CI 21-29) as compared with high-emission scenarios (SSP5-8.5).

INTERPRETATION: This study provides global evidence linking climate change to ARG dynamics in Salmonella. Warming and shifting precipitation patterns are associated with rising ARG abundance and are projected to further exacerbate AMR risks under high-emission scenarios (SSP2-4.5, SSP3-7.0, and SSP5-8.5). These findings highlight the need to integrate climate considerations into AMR surveillance and stewardship, providing a quantitative basis for climate-informed strategies to restrict future resistance escalation.

FUNDING: National Key Research and Development Program of China, the National Natural Science Foundation of China, Zhejiang Provincial Natural Science Foundation of China, and Beijing Municipal Sci-Tech Project on Ecology and Environment.

PMID:42190676 | DOI:10.1016/j.lanplh.2026.101445

Photosynth Res. 2026 May 25;164(3):31. doi: 10.1007/s11120-026-01218-0.

ABSTRACT

Photosynthetic microorganisms may show extracellular electron transfer (EET), in which some of the electrons generated by photosynthesis or respiration are lost from the cell. Most studies have focussed on cyanobacteria, with very few on eukaryotic algae. Here we demonstrate EET from the eukaryotic dinoflagellate alga Symbiodinium microadriaticum, a species that can form symbiosis with corals and other Cnidaria. We show that the EET involves diffusible electroactive species, which may represent a previously unsuspected route for communication between symbionts and hosts. We show that EET can be used to study photosynthetic and respiratory functions in the dinoflagellate. We also show that it can provide information on the effects of environmental stresses including changes in temperature (linked to coral bleaching), pH and light intensity. The electrochemical platform outlined in this study offers a novel tool for studying dinoflagellate physiology, the coral-dinoflagellate symbiosis, and the molecular mechanisms of bleaching.

PMID:42184070 | DOI:10.1007/s11120-026-01218-0

Wellcome Open Res. 2025 Oct 1;10:529. doi: 10.12688/wellcomeopenres.24735.1. eCollection 2025.

ABSTRACT

BACKGROUND: The COVID-19 pandemic exposed critical vulnerabilities in global laboratory supply chains, disrupting the availability of key reagents and jeopardising the continuity of genomic surveillance essential for epidemic response. Sustaining sequencing capacity during supply shortages requires practical, locally accessible alternatives to commercial kits.

METHODS: We developed ARTIC HELP (Homebrew Enzymes for Library Preparation), an open-source adaptation of the ARTIC nanopore sequencing protocol for viral genomic surveillance. We described cost-effective, generic replacements for all enzyme mixes used in tiling multiplex RT-PCR and the nanopore native barcoding workflow, including end-prep (EP), barcode ligation (BL), and adapter ligation (AL). Through systematic evaluation, we tested wild-type M-MLV reverse transcriptase and two types of proofreading DNA polymerases, (i) B-family Pfu-based polymerases fused to an Sso7d DNA-binding domain, and (ii) blends of A-family (Taq-based) and B-family (Pfu-based) polymerases, against standard reagents. We validated the workflow on clinical SARS-CoV-2 and Norovirus GII samples.

RESULTS: The HELP workflow delivered genome coverage comparable to the ARTIC LoCost protocol. For SARS-CoV-2 samples (Ct ≤28), wild-type M-MLV RT combined with selected Pfu or AB blend polymerases, alongside optimized HELP EP, BL, and AL mixes, achieved 84.0-99.6% genome coverage. For Norovirus GII samples (Ct ≤32), the HELP workflow enabled >85% coverage across six of eight genotypes tested. While some polymerases showed reduced performance at higher Ct values, they performed reliably at Ct <24, supporting their use as emergency alternatives in rapid outbreak-response sequencing when viral load is high and RNA quality sufficient.

CONCLUSIONS: ARTIC HELP provides a robust and flexible solution to maintain viral sequencing capacity when standard reagents are inaccessible or unaffordable. Our cost analysis highlights stark global disparities in reagent pricing driven by import fees and supply barriers, rather than protocol complexity, underscoring the need for equitable pricing models and local sourcing strategies. By giving laboratories more options for essential reagents, ARTIC HELP strengthens preparedness and resilience for future public health emergencies.

PMID:42181968 | PMC:PMC13197761 | DOI:10.12688/wellcomeopenres.24735.1

Plant Physiol Biochem. 2026 May 16;235:111371. doi: 10.1016/j.plaphy.2026.111371. Online ahead of print.

ABSTRACT

Apyrases (nucleoside triphosphate-diphosphohydrolases) are enzymes that regulate the concentration of NTP and NDP nucleotides in cells by removing their terminal phosphate. Two of the 7 apyrases in Arabidopsis, APY1 and APY2, are 87% identical in primary structure and play important roles in regulating auxin transport and plant growth. To clarify how these apyrases function, this report confirms their localization in purified nuclei and characterizes their enzymatic properties. Immunolocalization and immunoblot assays using a polyclonal antibody (2556) raised to a 24-mer peptide unique to APY1 showed that this calmodulin-binding APY was highly expressed in nuclei purified from etiolated Arabidopsis seedlings, just as a previously characterized calmodulin-binding apyrase, psNTP9, is highly expressed in purified nuclei of etiolated pea seedlings. Crude nuclear extracts assayed by mass spectroscopy identified the presence of APY1. Because nuclei purified from seedlings expressing APY1-GFP and APY2-GFP both showed the GFP signal, both APY1 and APY2 were likely present in the final preparation of APY, which eluted as a 48 kDa monomer from a molecular sieve column. As estimated by silver-staining after its separation on SDS-PAGE, the purified APY was >85% pure. It had a specific activity toward ATP and ADP substrates similar to that of other apyrases purified from plant and animal sources, but did not hydrolyze AMP substrates. These results favor those of prior reports that APY1/2 are nucleoside triphosphate-diphosphohydrolases, but differ from those of an earlier report that found HA-tagged APY1 extracted from light-grown Arabidopsis tissue did not hydrolyze ATP.

PMID:42176408 | DOI:10.1016/j.plaphy.2026.111371

BMC Bioinformatics. 2026 May 19. doi: 10.1186/s12859-026-06473-5. Online ahead of print.

ABSTRACT

BACKGROUND: Deep mutational scanning (DMS) provides comprehensive maps of protein variant effects but remains experimentally intensive. Machine learning (ML) approaches have the potential to reduce experimental burden of DMS by predicting the functional impact of substitutions from limited data.

RESULTS: We introduced a ML classifier trained on normalised DMS scores from SARS-CoV-2 main protease (Mpro) to categorise amino acid substitutions as functional (wild-type-like) or non-functional. Using brute-force feature selection, we identified minimal subsets of six substitution scores per residue that enable accurate classification of the remaining substitutions, achieving minimum (worst accuracy) scores exceeding 90%. Models including support vector machines, random forests, and logistic regression were evaluated without retraining (zero-shot prediction) against additional SARS-CoV-2 Mpro datasets and against unrelated datasets. The zero-shot performance of the models was strongest for other enzymes and more modest when applied to DMS systems that assess protein folding and/or protein-protein interactions.

CONCLUSION: The results show that targeted DMS combined with ML can reduce sequencing and reagent costs while preserving classification accuracy, offering a practical route to accelerate variant effect prediction.

PMID:42157089 | DOI:10.1186/s12859-026-06473-5

J Infect. 2026 May 18:106759. doi: 10.1016/j.jinf.2026.106759. Online ahead of print.

ABSTRACT

BACKGROUND: Coronaviruses such as SARS, SARS-CoV-2 and related Sarbeco-Coronaviruses continue to pose global health threats, underscoring the need for vaccines capable of inducing broad cross-sarbecovirus protection. The pEVAC-PS vaccine was developed using Digitally Immune Optimised Synthetic Vaccine (DIOSynVax) technology and pre-clinically selected for the ability to induce broadly protective immune responses across the Sarbecoviruses including SARS, SARS-CoV-2, and related viruses representing potential zoonotic spillovers. For this first-in-human study, the antigen was delivered as a DNA vaccine to enable thermostability and needle-free intradermal administration to support future deployment in resource-limited settings.

METHODS: This open label phase I dose escalation study investigated the safety, tolerability and immunogenicity of the pEVAC-PS vaccine candidate against SARS, SARS-CoV-2 and related Sarbeco Coronaviruses via needle-free intra-dermal delivery using the PharmaJet Tropis Device. Healthy volunteers aged 18 to 50 who had received two or three prior doses of COVID-19 vaccine, and without recent confirmed COVID-19 infection, were enrolled sequentially to receive a dose escalation regime of 0.2mg, 0.4mg, 0.8mg, and 1.2mg of pEVAC-PS, administered at day zero and day 28. The primary outcomes were safety and reactogenicity, documented by solicited and unsolicited adverse events, serious adverse events and adverse events of special interest. Secondary outcomes were immunogenicity measured primarily by humoral responses to SARS-CoV-1 and SARS-CoV-2 antigens at day 56 (28 days after the second dose of vaccine). International Clinical Trials Registry Platform registered, ISRCTN87813400.

FINDINGS: Between December 2021 and September 2023, a total of 39 volunteers were vaccinated. The vaccine was well tolerated at all four doses with no significant safety concerns elicited. Interpretation of immunogenicity outcomes was influenced by high baseline antibody levels and heterogeneous exposure histories due to ongoing waves of Omicron variant infections during recruitment, which differed across dose-escalation cohorts and introduced unavoidable immune bias.

INTERPRETATION: Needle-free intradermal delivery of this novel computationally designed PanSarbeco vaccine was safe and well tolerated. Although immunogenicity was modest in the context of substantial pre-existing immunity, participants developed measurable responses to conserved, vaccine-encoded sarbecovirus epitopes, supporting the feasibility of this antigen design strategy.

PMID:42155675 | DOI:10.1016/j.jinf.2026.106759

Elife. 2026 May 19;14:RP107191. doi: 10.7554/eLife.107191.

ABSTRACT

Trypanosoma brucei, the causal agent of Human and Animal African trypanosomiasis proliferates in the extracellular milieu of mammals. It acquires host macromolecular nutrients by receptor-mediated endocytosis. The best characterised cell surface receptor is for transferrin (TfR), and it has been reported to be preferentially localised in the flagellar pocket domain of the plasma membrane, the sole site of endocytosis. In this location, the TfR may be inaccessible to adaptive immune system effectors. The T. brucei genome encodes ~15 TfR variants, and here we compared two, the first attached to the plasma membrane by a single glycosylphosphatidylinositol (GPI)-anchor and the other by two. Transferrin uptake kinetics were similar and rapid for both. Unexpectedly, initial binding of transferrin occurred over the whole cell surface suggesting the TfR was not localised solely in the flagellar pocket. This localisation was confirmed by immunofluorescence assays and was independent of the number of GPI-anchors. Two other GPI-anchored receptors were investigated to determine whether localisation to the whole cell surface was a general property of GPI-anchored receptors. Haptoglobin-haemoglobin uptake assays and immunofluorescence localisation of complement factor H receptor showed both were also whole cell surface localised. The mechanisms by which trypanosome receptors are protected from antibody-mediated attack are more complex than hiding in a pocket.

PMID:42153621 | DOI:10.7554/eLife.107191

J Immunol. 2026 May 14;215(5):vkag071. doi: 10.1093/jimmun/vkag071.

NO ABSTRACT

PMID:42153523 | DOI:10.1093/jimmun/vkag071

PLoS Negl Trop Dis. 2026 May 18;20(5):e0013343. doi: 10.1371/journal.pntd.0013343. Online ahead of print.

ABSTRACT

Large host-virus association databases are increasingly used to explore broad questions in disease ecology, particularly around host range, pathogen diversity, and the potential for spillover. While these databases have been instrumental in large-scale synthesis of host- pathogen biogeography and zoonotic risk, their potential role in addressing fine-scale questions about pathogen prevalence, maintenance, and transmission dynamics remains underexplored. In this study, we build on previous efforts to assess how different types of data, including both entries in databases and the original studies they draw from, can support targeted research on zoonotic spillover. We selected two zoonotic diseases, Ebola virus disease and Lassa fever, which are characterised by recurrent spillover events and outbreaks in sub-Saharan Africa. We searched the VIRION database for entries corresponding to the respective viral taxa, the genus Orthoebolavirus and the species Mammarenavirus lassaense, and used these entries as case studies. We evaluated the extent to which databases capture crucial contextual metadata, such as spatial and temporal resolution, negative results, and measures of viral load. Guided by a conceptual framework of factors that lead to spillover, we demonstrate that while host- virus databases are valuable for addressing high-level patterns, fine-scale investigations of spillover require specific studies with detailed epidemiological data. Our study adds to a growing body of literature offering practical recommendations for database users and managers and highlights how these tools can be used as starting points in spillover research.

PMID:42149938 | DOI:10.1371/journal.pntd.0013343

Microb Genom. 2026 May;12(5). doi: 10.1099/mgen.0.001635.

ABSTRACT

Ornithobacterium hominis is a recently described Gram-negative bacterium that colonizes the human nasopharynx and may be associated with poor upper respiratory tract health. Here, we describe the isolation of O. hominis from samples collected from a South African birth cohort, creating the first archive of cultured strains of the species from Africa. Sequenced genomes from this archive reveal that South African O. hominis is more similar to Australian strains than those from Southeast Asia and that it may share genes with other members of the microbiome that are relevant for virulence, colonization and antibiotic resistance. Leveraging existing microbiome data from the cohort, O. hominis was found to be closely associated with bacterial co-colonizers that are rare in non-carrier individuals, including Suttonella, Rappaport, Helcococcus, Lwoffella, Moraxella and Gracilibacteria. Their collective acquisition has a significant impact on the diversity of nasopharyngeal communities that contain O. hominis. Individuals who have not yet acquired O. hominis have a higher abundance of Lwoffella lincolnii than individuals who never acquire O. hominis, suggesting that this could be a precursor state for successful colonization.

PMID:42149113 | DOI:10.1099/mgen.0.001635

Biomed Opt Express. 2026 Apr 21;17(5):2523-2532. doi: 10.1364/BOE.586641. eCollection 2026 May 1.

ABSTRACT

Malaria remains a major global health challenge, particularly in low-resource settings where diagnostic infrastructure is limited. The gold standard diagnostic is manual light microscopy which is slow, labor-intensive, and dependent on expert interpretation limiting the management of malaria. Here, we present a magneto-optical (MO) imaging approach that exploits the magnetic anisotropy and optical dichroism of hemozoin crystals to achieve label-free, quantitative detection of malaria infection within a conventional polarizing microscope. In our implementation, an external magnetic field induces torque on the paramagnetic hemozoin crystals, aligning their long axes along the field vector. This alignment modulates the optical anisotropy of the specimen, producing a measurable field-dependent change in transmitted polarization contrast. Unlike previously reported standalone magneto-optical devices, which rely on bulk optical scattering or transmission modulation, our approach integrates MO directly into a conventional polarizing microscope setup, allowing simultaneous imaging and quantitative MO signal analysis at the microscopic scale. By integrating ratiometric intensity analysis and threshold-based segmentation metrics, we advance malaria imaging beyond purely observational assessment, enabling a quantitative correlation between MO signal strength and hemozoin concentration, and thus, with parasite developmental stage. These metrics are also well-suited for automated malaria diagnostics, as they provide stable, objective parameters that can be reliably computed without expert intervention. Moreover, because microscopy expertise is already well established in many malaria-endemic regions, embedding this approach within the familiar framework of microscopy offers a practical and rapid pathway for integrating the technique into routine malaria diagnosis.

PMID:42145676 | PMC:PMC13178579 | DOI:10.1364/BOE.586641