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PubMed2026

Genetic Diversity and Pathogenicity of Thielaviopsis paradoxa Isolates and Implications for Coconut Palm Disease Management.

Thielaviopsis paradoxa is an important soilborne pathogen causing bleeding disease and stem rot of coconut and other palm species, posing a serious threat to coconut production in Hainan Province, China. This study investigated the biological characteristics, pathogenic variability, and genetic diversity of T. paradoxa isolates collected from coconut palms in this region, where population-level data remain limited. Isolates exhibited variability in mycelial growth and sporulation under different temperature, pH, and nutrient conditions, indicating physiological differentiation among strains. Pathogenicity assays across multiple coconut varieties revealed four pathogenicity types, with some isolates consistently showing greater aggressiveness. Genetic analysis based on ISSR markers revealed a high level of genetic diversity (82.96% polymorphism). Genetic clustering showed partial associations with geographic origin, host source, and pathogenicity patterns; however, these relationships are correlative and do not imply causality. Overall, this study provides the first region-specific synthesis of physiological traits, pathogenic variability, and ISSR-based genetic diversity of T. paradoxa in Hainan, contributing baseline information for future population genomic studies and supporting the development of improved disease management strategies for coconut palms.[Formula: see text] Copyright © 2026 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

China↗

PubMed2026

Mapping Wastewater Pathogens and Their Associated Environmental and Public Health Risk Factors: A Systematic Review and Meta-Analysis.

BACKGROUND: Wastewater-based epidemiology (WBE) has emerged as a critical tool for public health surveillance, yet its application across diverse pathogens and geographical settings remains inconsistent. This systematic review synthesizes global evidence on wastewater surveillance to identify associated risk factors. METHODS: Following PRISMA 2020 guidelines (PROSPERO: CRD420261297382), a systematic search was conducted across PubMed, Scopus, Google Scholar, and Web of Science for studies published between 2000 and 2025. RESULTS: Thirty-nine peer-reviewed studies were included. The evidence base is geographically skewed toward the European Region (48.7%) and the Americas (23.1%), with significant underrepresentation in LMICs. Viruses were the primary biological target (89.7%), followed by bacteria (7.7%) and parasites (2.6%). A proportion meta-analysis of 31 eligible studies demonstrated a pooled wastewater pathogen detection prevalence of 62% (95% CI: 47.5-74.6%), with the European Region yielding the highest regional estimate (73%) and the African Region the lowest (8.3%). Conventional PCR and sequencing methods showed higher pooled detection rates (92.4% and 90.1%, respectively) than RT-qPCR (47.9%). CONCLUSION: WBE provides a robust early-warning system indicating a need for broader pathogen diversity, incorporating bacterial and parasitic surveillance and expansion into rural and resource-limited regions.

Contamination↗

PubMed2026

Modeling reptile virus infection in vitro using Python regius airway organoids.

Zoonoses pose substantial global health risks, highlighting the need to better understand animal-to-human transmission. Reptiles are increasingly recognized as hosts of diverse pathogens, including numerous viruses, yet the diversity and prevalence of reptile pathogens, as well as their potential risk to humans, remain poorly understood. Here, we establish and characterize airway organoids derived from Python regius, providing an in vitro model to study reptile airway infection. Through de novo assembly of a Python regius reference genome, we characterize airway organoids at single-cell resolution, which suggests the presence of diverse cell populations including ionocytes, ciliated, secretory, goblet, endocrine, tuft, and basal cells. The organoids support productive infection with Ball Python Nidovirus (BPNV) and mount a robust epithelial antiviral response through the induction of interferon-stimulated genes, cytokines, and genes involved in chemical defense. As a proof-of-concept, treating organoids with antiviral drugs during infection reduces BPNV levels, highlighting the model's utility for drug testing. By providing a reductionist system of the serpentes airway, these organoids constitute a physiologically relevant in vitro model to study reptile viruses and host-pathogen interactions in their native host.

Animals↗

PubMed2026

TRIM21 induces selective autophagy of viruses and bacteria.

TRIM21 is an exceptionally versatile ubiquitin ligase that can be directed by antibodies to target oligomeric protein scaffolds, viral capsids, and proteopathic aggregates for intracellular degradation. How the cell degrades these typically resistant substrates remains poorly understood. To address this, we used TRIM21 viral restriction to create a genome-wide phenotypic screen for antibody-dependent capsid degradation. We identify an antimicrobial selective macroautophagy pathway in mammalian cells, which we term "antibody-directed xenophagy" (ADX). We show that this mechanism restricts structurally diverse pathogens, including adenovirus and Salmonella. Using quantitative microscopy, we demonstrate that TRIM21 rapidly intercepts antibody-pathogen complexes, leading to ubiquitin ligase activation. Following this, selective autophagy adaptors are recruited, and viral cargoes are delivered to lysosomes. This process reduces Salmonella pathology and bacterial tissue invasion in mice. We propose that TRIM21 evolved through competition with pathogens to induce autophagy of diverse and complex substrates, potentially explaining its versatility for targeted protein degradation.

TRIM21 Protein↗

PubMed2025

A major trade-off between growth and defense in Arabidopsis thaliana can vanish in field conditions.

When wild plants defend themselves from pathogens, this often comes with a trade-off: the same genes that protect a plant from disease can also reduce its growth and fecundity in the absence of pathogens. One protein implicated in a major growth-defense trade-off is ACCELERATED CELL DEATH 6 (ACD6), an ion channel that modulates salicylic acid (SA) synthesis to potentiate a wide range of defenses. Wild Arabidopsis thaliana populations maintain significant functional variation at the ACD6 locus, with some alleles making the protein hyperactive. In the greenhouse, plants with hyperactive ACD6 alleles are resistant to diverse pathogens, yet they are of smaller stature, their leaves senesce earlier, and they set fewer seeds compared to plants with the standard allele. We hypothesized that ACD6 hyperactivity would not only affect the growth of microbial pathogens but also more generally change leaf microbiome assembly. To test this in an ecologically meaningful context, we compared plants with hyperactive, standard, and defective ACD6 alleles in the same field-collected soil, both outdoors and in naturally lit and climate-controlled indoor conditions, taking advantage of near-isogenic lines as well as a natural accession and a CRISPR-edited derivative. We surveyed visual phenotypes, gene expression, hormone levels, seed production, and the microbiome in each environment. The genetic precision of CRISPR-edited plants allowed us to conclude that ACD6 genotype had no effect on mature field plants in our setting, despite reproducibly dramatic effects on greenhouse plants. We conclude that additional abiotic and/or microbial signals present outdoors-but not in the greenhouse-greatly modulate ACD6 activity. This raises the possibility that the fitness costs of other commonly studied immune system genes may be grossly misjudged without field studies.

Arabidopsis↗

PubMed2025

Temporal and geographical lineage dynamics of invasive Streptococcus pyogenes in Australia from 2011 to 2023: a retrospective, multicentre, clinical and genomic epidemiology study.

BACKGROUND: Defining the temporal dynamics of invasive Streptococcus pyogenes (group A Streptococcus) and differences between hyperendemic and lower-incidence regions provides crucial insights into pathogen evolution and, in turn, informs preventive measures. We aimed to examine the clinical and temporal lineage dynamics of S pyogenes across different disease settings in Australia to improve understanding of drivers of pathogen diversity. METHODS: In this retrospective, multicentre, clinical and genomic epidemiology study, we identified cases of invasive S pyogenes infection from normally sterile sites between Jan 1, 2011, and Feb 28, 2023. Data were collected from five hospital networks across low-incidence regions in temperate southeast Australia and the hyperendemic, tropical, and largely remote Top End of the Northern Territory of Australia. The crude incidence rate ratio (IRR) of bloodstream S pyogenes infection comparing the Top End and southeast Australia and in First Nations people compared with non-First Nations people was estimated by quasi-Poisson regression. We estimated odds ratios (ORs) of intensive care unit (ICU) admission, in-hospital mortality, and 30-day mortality for the Top End versus southeast Australia using logistic regression. Retrieved and successfully sequenced isolates were assigned lineages at whole-genome resolution. Temporal trends in the composition of co-circulating lineages were compared between the two regions. We used an S pyogenes-specific multistrain simulated transmission model to examine the relationship between host population-specific parameters and observed pathogen lineage dynamics. The prevalence of accessory genes (those present in 5-95% of all genomes) was compared across geographies and temporal periods to investigate genomic drivers of diversity. FINDINGS: We identified 500 cases of invasive S pyogenes infection in patients in the Top End and 495 cases in patients in southeast Australia. The crude IRR of bloodstream infection for the Top End compared with southeast Australia was 5·97 (95% CI 4·61-7·73) across the entire study period; in the Top End, infection disproportionately affected First Nations people compared with non-First Nations people (5·41, 4·28-6·89). The odds of in-hospital mortality (OR 0·43, 95% CI 0·26-0·70), 30-day mortality (0·38, 0·23-0·63), and ICU admission (0·42, 0·30-0·59) were lower in the Top End than in southeast Australia. Longitudinal lineage analysis of 642 S pyogenes genomes identified waves of replacement with distinct lineages in the Top End, whereas southeast Australia had a small number of dominant lineages that persisted and cycled in frequency. The transmission model qualitatively reproduced a similar pattern of replacement with distinct lineages when using a high transmission rate, small population size, and high levels of human movement-characteristics similar to those of communities in the hyperendemic Top End. Using a lower transmission rate, larger population size, and lower levels of migration similar to those of communities in urbanised southeast Australia, the transmission model qualitatively reproduced a pattern of dominant lineages that cycled in frequency. Despite distinct circulating lineages, the prevalence of accessory genes in the bacterial population was maintained across geographies and temporal periods. INTERPRETATION: In a hyperendemic setting, the replacement of distinct S pyogenes lineages occurred in waves, which could be linked to the disproportionate burden of disease and sparse human population in this setting. The maintenance of bacterial gene frequency could be consistent with multilocus selection. These findings suggest that lineage-specific interventions-such as vaccines under development-should consider disease setting and, without broad cross-protection, might lead to lineage replacement. FUNDING: National Health and Medical Research Council, and Leducq Foundation.

Humans↗

PubMed2026

Bridging the airway microbiome and targeted therapy in bronchiectasis: multi-omics insights, endotypes and emerging therapies.

Bronchiectasis is a heterogeneous chronic airway disease primarily driven by persistent infection, microbial dysbiosis and dysregulated host immunity. While culture-based microbiology has historically informed clinical management, advances in high-throughput sequencing and multi-omic technologies have transformed our understanding of the airway ecosystem, revealing that disease activity is shaped not only by individual pathogens, but by complex and dynamic host-microbe interactions. Despite the breadth of descriptive microbiome data, translation into clinically actionable diagnostics or therapies has been limited. Importantly, cross-sectional correlations between microbiota and inflammation do not establish cause and effect, underscoring the need to embed host-microbiome profiling within both longitudinal and interventional therapeutic trials. In this review, we critically appraise current microbial and host multi-omics research in bronchiectasis, integrating microbiome studies with host inflammatory, proteomic and immunophenotyping data. We highlight themes emerging across cohorts, including low microbial diversity, pathogen dominance, loss of commensal networks and neutrophil-driven inflammation, and discuss how these features align with biological endotypes associated with exacerbations and treatment response. Drawing on lessons from host-directed therapeutic successes, we examine translational roadblocks limiting microbiome-guided care. We further review emerging microbiome-modulating strategies such as pathogen-specific biologics, bacteriophage therapy, live biotherapeutic products, biofilm-targeting adjuncts and precision antibiotic stewardship. Finally, we propose a roadmap toward microbiome-informed precision medicine through harmonised methodologies, integration of host and microbial biomarkers into clinical trials, and embedding multi-omics pipelines within large international registries. Collectively, these advances have the potential to shift bronchiectasis research and clinical management towards rationally designed, precision medicine-driven therapeutic strategies.

Humans↗

PubMed2026

The Hidden Diversity of Benyviridae and their Polymyxa Vectors: A Comparative Analysis.

The Benyviridae family encompasses multipartite soil-borne phytoviruses characterized by rod-shaped virions and positive single-stranded RNA genomes. The family is mostly known for its type species, the beet necrotic yellow vein virus, the causal agent of rhizomania on sugar beet. However, the recent description of candidate Benyviridae species and "beny-like" sequences suggests a far greater diversity than previously recognized. Also, their increasing relevance in agriculture has drawn attention to this family of viruses. In this review, we provide a comparative analysis of Benyviridae viruses, including newly identified emerging relatives. We highlight recent advances in understanding their diversity, pathogenicity, and interaction with plant hosts and their plasmodiophorid vectors, Polymyxa spp., that remain poorly characterized. Finally, we identify critical knowledge gaps and exciting opportunities-particularly in vector biology, host interactions, and the ecological dynamics of viral spread-that will shape the research ahead.

Plant Viruses↗

PubMed2026

Mannheimia haemolytica strain-level diversity in cattle populations.

High-resolution genomic characterization is essential for understanding diversity, pathogenicity, and transmission dynamics of bacterial pathogens. Mannheimia haemolytica (Mh) is the most consequential bacterial agent associated with bovine respiratory disease (BRD) in cattle, as a leading cause of morbidity, mortality, and antimicrobial use. Historically, BRD pathogens, including Mh, have been studied using culture or PCR approaches that provided limited ability to characterize fine-scale genomic variation across communities. Here, we evaluated target-enriched (TE) shotgun sequencing, a culture-independent method capable of strain-level resolution within metagenomic data, for detecting and characterizing Mh in comparison with qPCR and 16S rRNA gene sequencing. Nasal swabs (10 individual and 2 composited DNA samples per pen) and environmental samples (three ropes hung on pen rails and three water bowl swabs per pen) were collected from four pens in each of five distinct cattle populations. DNA was extracted for TE sequencing to identify Mh at both species and genomic sequence variant (GSV) levels, and to characterize antimicrobial resistance genes across the bacterial communities. qPCR was performed to quantify Mh genome copies, and 16S rRNA gene sequencing was used to assess the broader respiratory microbiome. TE sequencing identified Mh in 100% of TE-tested samples and classified multiple GSVs in all but 3 of 121 samples. GSV profiles clustered within housing groups and varied across cattle populations, indicating structured strain-level diversity. In contrast, Mannheimia spp. were detected in only 47.7% of samples by 16S rRNA sequencing. These findings demonstrate that TE sequencing enables sensitive, strain-level characterization of Mh in cattle and environmental samples and reveals substantial within-population genomic diversity not captured by conventional approaches.IMPORTANCETarget-enriched shotgun sequencing enabled sensitive, strain-level detection of Mannheimia haemolytica (Mh), revealing multiple co-circulating genomic sequence variants (GSVs) within and among cattle groups. This demonstrates greater genetic variability of Mh populations in beef cattle than has been previously recognized. The clustering of GSVs within housing groups, together with the overlap between respiratory and environmental samples, is consistent with the hypothesis that contagious transmission contributes to Mh ecology. These results highlight the potential utility of composite nasal swab and environmental samples for future studies evaluating relationships between Mh genomic variation and disease risk.

Animals↗

PubMed2026

Molecular Bases and Genetic Design of Rice Disease Resistance for Optimized Yield and Sustainable Agriculture.

Rice diseases continue to undermine yield stability and threaten the sustainability of rice production. The central challenge is therefore not simply to maximize immune activation, but to identify genetic interventions that remain effective across diverse pathogen races and environmental conditions without imposing excessive penalties on growth or yield. Here, we synthesize the molecular basis of rice immunity from a design-oriented perspective. We first examine cell-surface pattern-recognition receptors and intracellular nucleotide-binding leucine-rich repeat receptors, and then assess the shared signaling hubs and defence outputs that connect pathogen perception to antimicrobial responses. Rather than treating these components as equivalent breeding targets, we compare their translational potential according to resistance spectrum, anticipated durability, tunability, pleiotropic risk, and the strength of field evidence. We further discuss breeding strategies based on receptor engineering, editing of susceptibility genes and cis-regulatory elements, post-translational motif engineering, pathogen-inducible and upstream open reading frame-mediated regulation, resistance-gene stacking and artificial intelligence-assisted prediction. We argue that rational resistance design in rice should move beyond constitutive immune activation toward allele-specific, quantitative, spatially restricted and infection-responsive regulation. Integrating mechanistic insights with precision genome editing, accelerated breeding and responsible deployment offers a practical route to durable, yield-compatible disease resistance while reducing dependence on chemical control.

breeding strategy↗

PubMed2026

From commensal to pathobiont: The emergence of virulence-enhanced Escherichia coli in China's food-animal systems - insights with future implications.

A fundamental shift in Escherichia coli epidemiology is being driven by convergence of virulence determinants and antimicrobial resistance within linked human-animal-environment systems. In China, the rapid growth of food-animal production, extensive antimicrobial use, and complex food networks are accelerating the emergence and dissemination of virulence-enhanced E. coli pathobionts. This review synthesizes recent epidemiological, genomics, and outbreak data to characterize China's evolving landscape of food-animal-associated E. coli. We highlight a significant shift from classical pathotypes to hybrid lineages that simultaneously carry virulence factors and last-resort antibiotic resistance determinants, including mcr-1, tet(X4), and blaNDM. These traits disseminate rapidly via plasmid-mediated horizontal gene transfer, facilitating rapid adaptation and enabling cross-sectoral One Health transmission. National surveillance, foodborne outbreak investigations, and whole-genome sequencing data show that food-animal reservoirs are active evolutionary niches that drive pathogen diversity and fitness, rather than serving merely as contamination sources. Whole-genome sequencing also pinpoints high-risk clones (e.g., ST394) and plasmid-mediated co-selection of virulence and AMR. The emergence of hybrid pathotypes (e.g., STEC/ETEC) and AMR-virulence co-selection challenges traditional classification and limits the effectiveness of conventional surveillance approaches. The 2017 colistin ban reduced mcr-1, yet ongoing resistance and emerging tet(X4) demand integrated surveillance. Collectively, these findings call for reconceptualizing E. coli as a dynamic genomic entity embedded within a unified ecological network. Addressing this threat requires an integrated One Health strategy including genomic surveillance, agricultural antimicrobial stewardship, and coordinated food-environment-clinical monitoring to prevent high-risk clone emergence and global spread.

Animals↗

PubMed2024

Model-directed generation of artificial CRISPR-Cas13a guide RNA sequences improves nucleic acid detection.

CRISPR guide RNA sequences deriving exactly from natural sequences may not perform optimally in every application. Here we implement and evaluate algorithms for designing maximally fit, artificial CRISPR-Cas13a guides with multiple mismatches to natural sequences that are tailored for diagnostic applications. These guides offer more sensitive detection of diverse pathogens and discrimination of pathogen variants compared with guides derived directly from natural sequences and illuminate design principles that broaden Cas13a targeting.

CRISPR-Cas Systems↗

PubMed2026

Diverse haplotypes at a complex Solanum americanum locus confer resistance to Phytophthora infestans and P. capsici.

Plants encounter diverse pathogens and have evolved a two-layered innate immune system to detect pathogen molecules and activate defense mechanisms that restrict infection. Most cloned plant Resistance (R) genes encode NLR immune receptors. NLR genes are often found in clusters of paralogs with sequence and copy number variation; whether these NLR clusters evolve in response to single or multiple pathogens has been unclear. We report here the isolation of a Phytophthora capsici resistance gene, Rpc2, along with a novel P. infestans resistance gene, Rpi-amr5, from two Solanum americanum accessions. These orthologous genes reside in the Rpi-amr1 cluster, which has previously been associated with resistance to P. infestans. By screening RXLR effector libraries of P. infestans and P. capsici, we identified multiple effectors recognised by both NLRs. Our findings highlight the complexity of NLR clusters and evolution driven by interactions with multiple pathogens. This work will underpin efforts to elevate resistance against Phytophthora pathogens and enhances our understanding of NLR evolution.

Journal Article↗

PubMed2025

Multiple effectors trigger non-host resistance in Solanum americanum against Pseudomonas syringae.

Wild plant species are threatened by diverse pathogens, but disease symptoms are rarely observed in nature. This suggests that wild plants harbor valuable sources of resistance. In this study, we show that the model bacterial pathogen Pseudomonas syringae pv. tomato (Pto) DC3000 triggered defense responses in all tested accessions of a wild Solanaceae species, Solanum americanum. Pto DC3000-triggered immunity in S. americanum required a type III secretion system. We show that seven Pto DC3000 effectors (AvrPto, HopAD1, HopAM1, HopC1, HopAA1-1, HopM1, and AvrE1) triggered hypersensitive responses (HR) in S. americanum accession SP2273. Significantly, sequential deletion of the HR-triggering effectors from Pto DC3000 resulted in enhanced virulence in S. americanum. However, the well-conserved effectors, HopM1 and AvrE1, were indispensable for virulence. We conclude that the immunity triggered by multiple effectors contributes to nonhost resistance in S. americanum against P. syringae. We propose that the identification of the corresponding disease resistance genes for HopM1 and AvrE1 in S. americanum would accelerate the development of durable immunity to P. syringae pathogens in Solanaceae crops.

Disease Resistance↗

PubMed2026

Emerging food- and waterborne pathogen Arcobacter in wastewater: diversity and antibiotic resistance.

Arcobacter spp. are emerging food- and waterborne pathogens frequently detected in wastewater. Despite their high abundance in wastewater, Arcobacter diversity, antibiotic resistance, and genomic traits remain poorly characterized. To address these knowledge gaps, we conducted a comprehensive study of Arcobacter spp. in influent, effluent, and activated sludge from a Finnish wastewater treatment plant using full-length 16S rRNA gene sequencing, isolate-based genomics, and phenotypic antibiotic susceptibility testing. Arcobacter spp. were highly abundant in raw sewage but substantially removed during treatment. Four Arcobacter species were identified, dominated by Arcobacter cryaerophilus and Arcobacter suis. A proportion of amplicon sequence variants unclassified to species-level revealed potentially unexplored Arcobacter diversity. For the first time, we observed intragenomic variability in 16S rRNA gene copies of A. cryaerophilus, highlighting the importance of integrating culture-based and culture-independent approaches. Phenotypic testing revealed high proportions of non-wild-type isolates for clinically relevant antibiotics, including ampicillin, cefotaxime, tetracycline, and erythromycin. Genomic analyses showed that antibiotic resistance profiles were primarily mediated by chromosomally encoded determinants, including β-lactamases, efflux systems, and point mutations. Additionally, a broad arsenal of chromosomal and plasmid-borne resistance genes to heavy metals, biocides, and organic solvents was detected, reflecting adaptations to the wastewater environment. These findings provide novel insights into Arcobacter species-level diversity, resistance mechanisms, and ecological adaptations in anthropogenically influenced environments. The study highlights the significance of Arcobacter for public health and establishes a foundation for further research.IMPORTANCEArcobacter spp. are emerging human and animal pathogens that exhibit increasing resistance to clinically relevant antibiotics. Most community-acquired infections are linked to exposure through contaminated food and water, yet studies investigating their occurrence and diversity in wastewater remain scarce. Here, we focus on wastewater as an abundant source of Arcobacter spp. and a potential dissemination route contributing to downstream contamination of surface waters, irrigated soils, and possibly the food chain. By characterizing the species-level diversity, genomic traits, and antibiotic resistance profiles of Arcobacter spp. in wastewater, this study provides critical insights into the ecology and epidemiology of this ubiquitous genus.

Arcobacter↗

PubMed2025

Understanding Mycobacterium tuberculosis through its genomic diversity and evolution.

Pathogen evolution and genomic diversity are shaped by specific host immune pressures and therapeutic interventions. Analysis of the extant genomes of circulating strains of Mycobacterium tuberculosis, a leading cause of infectious mortality that has co-evolved with humans for thousands of years, can provide new insights into host-pathogen interactions that underlie specific aspects of pathogenesis and onward transmission. With the explosion in the number of fully sequenced M. tuberculosis strains that are now paired with detailed clinical data, there are new opportunities to understand the evolutionary basis for and consequences of M. tuberculosis strain diversity. This review examines mechanistic findings that have emerged from pairing whole genome sequencing data and evolutionary analysis with functional dissection of specific bacterial variants. These include improved understanding of secreted effectors that modulate the properties and migratory behavior of infected macrophages as well as bacterial genetic alterations important for survival within hypoxic microenvironments. Genomic, evolutionary, and functional analyses across diverse M. tuberculosis strains will identify prominent bacterial adaptations to their human hosts and shape our understanding of TB disease biology and the host immune response.

Mycobacterium tuberculosis↗

PubMed2026

Genetic heterogeneity and pathogenic potential of historical Crimean-Congo hemorrhagic fever virus isolates in China.

The Crimean-Congo hemorrhagic fever virus (CCHFV) poses a significant public health threat. In China, CCHFV has been circulating for decades, yet the genomic diversity and pathogenic potential of the circulating strains remain poorly characterized, hindering risk assessment and countermeasure development. In this study, we recovered 24 historical CCHFV strains isolated between 1966 and 2004 from humans, ticks and jerboas in Xinjiang Uyghur Autonomous Region of China. Whole-genome sequencing was performed, followed by comprehensive analyses of their phylogenetic relationships, in vitro infectivity and in vivo pathogenicity. Phylogenetic analyses revealed high genetic heterogeneity, identifying seven genotypes for the L segment, nine for the M segment (including a novel Asia 4 genotype), and nine for the S segment. Amino acid mutation analysis revealed that the mucin-like domain (MLD) of the glycoprotein (GP) exhibited the highest mutation rate, contributing substantially to sequence diversity. In vitro, Asia 2 (75024) and Asia 3 (79121M18) strains exhibited robust replication in monkey-, hamster-, and human-derived cell lines. In C57BL/6 mice, all four representative strains induced viral replication and specific antibody responses (IgM and IgG), causing mild to moderate pathological damage in the liver, spleen, and kidneys. In IFNAR-/- mice, virulence varied markedly among representative strains: Asia 2 and Asia 3 strains were highly lethal (LD50 < 1 TCID50), Asia 1 was moderately virulent (LD50 = 142.5 TCID50), and Asia 4 exhibited atypical, non-dose-dependent mortality. Collectively, our work reports a novel Asia 4 genotype and suggests strain- and lineage-associated differences in virulence for CCHFV in China, providing critical insights for surveillance and targeted countermeasure development.

Animals↗

PubMed2026

Bacterial stress responses lower mRNA-protein level correlations.

Diverse bacterial pathogens have evolved complex regulatory mechanisms to adapt to various environmental stresses during infection. The uncertainty in mRNA-protein levels in response to environmental stressors complicates our understanding of bacterial physiology and their adaptation to stressful environments. To examine this issue, we have integrated transcriptomics and proteomics data on three human bacterial pathogens: Salmonella enterica Typhimurium, Yersinia pseudotuberculosis, and Staphylococcus aureus under 10 infection-relevant stress conditions. We observed positive correlations between mRNA and protein levels, which were decreased under different stress conditions. Essential genes exhibited higher expression levels with lower variation across the conditions and stronger mRNA-protein correlations compared to nonessential genes, highlighting their critical role in bacterial adaptability and survival. Moreover, we identified a substantial number of genes with stress-induced noncorrelating mRNA-protein levels, particularly under conditions triggering strong stress responses. Particularly this level was dramatically lowered for osmotic stress-specific genes affected by impaired translational activity under osmotic stress. Our findings highlight the prevalence of noncorrelating mRNA-protein levels and the potential role of posttranslational modifications in modulating protein levels in response to environmental stressors during infection. This study provides a comprehensive framework for integrating transcriptomics and proteomics data and identifies potential gene products that might significantly impact the ability of diverse bacterial pathogens to adapt to hostile infection environments.

RNA, Messenger↗