Search Results (1,214)

Sporothrix schenckii is a pathogenic fungus with both clinical and environmental origins that was traditionally described as a single species but is increasingly recognized as being genetically diverse. In this study, we analyzed multiple isolates recovered from human sporotrichosis cases and environmental sources across Latin America (Mexico, Guatemala, Colombia). We conducted a polyphasic analysis of 16 isolates, integrating morphological data with multilocus sequence analysis (MLSA) targeting the internal transcribed spacer (ITS), calmodulin (CAL), β-tubulin (BT2), and translation elongation factor 1-α (TEF) gene regions. Phylogenetic relationships were resolved via maximum likelihood, and genetic structure was corroborated via four independent clustering methods: minimum spanning tree, principal component analysis, multidimensional scaling, and self-organizing maps. MLSA reidentified six isolates as S. globosa and confirmed the absence of S. brasiliensis in the cohort. The remaining S. schenckii s. str. isolates were resolved into three clades (A, B, and C). Notably, clade B (EH748, EH194, and EH257) formed a genetically divergent cluster with the highest nucleotide diversity (π = 0.03556) and was consistently segregated by all clustering algorithms. Clinical and environmental isolates were phylogenetically intermingled, supporting an active environmental reservoir for human infections. Phenotypic data, including colony size and conidial and yeast dimensions, varied but did not clearly distinguish between clinical and environmental origins. Our study provides compelling molecular evidence for a previously unrecognized, highly divergent clade within S. schenckii s. str., indicative of ongoing cryptic speciation. These findings refine the taxonomy of medically important Sporothrix species and reveal a distinct epidemiological profile for sporotrichosis in the studied regions, separate from the S. brasiliensis-driven epizootic. This highlights the critical role of molecular surveillance for accurate diagnosis, treatment, and public health strategies. Full article

Vibrio is a genus of ubiquitous aquatic bacteria that includes numerous pathogenic species. Their remarkable genomic plasticity and rapid evolution make them of particular interest from both clinical and ecological perspectives. Successful infection by Vibrio species often relies on multiple virulence factors, including secreted enzymes. Here, we report the characterization of a novel environmental Vibrio strain isolated from a wild octopus that developed fulminant septicaemia accompanied by widespread soft tissue lysis. These severe symptoms prompted a detailed investigation into the bacterium’s identity and enzymatic profile, focused on proteases as potential virulence factors. Multi-locus sequence analysis placed the isolate within the Harveyi clade but revealed no perfect match to known strains, supporting its designation as a novel strain. Biochemical assays demonstrated strong proteolytic—including collagenolytic—activity, which makes this strain a promising source of enzymes for biotechnological applications. Full article

Postharvest diseases caused by various fungal pathogens pose a significant threat to fruit quality, storage, and market value, making their identification and biological characterization essential for effective management strategies. This study examines the morphological and phylogenetic characteristics of Alternaria, Botryosphaeria, Pestalotiopsis, and Trichothecium species associated with loquat fruit rot in Yunnan, China. In May 2023, fruit rot of loquat in Yunnan, China, was classified into four types: ring rot, brown spot, black spot, and soft rot, with incidence rates of 4%, 6%, 6%, and 12%, respectively. Based on morphological features and molecular approaches, two strains of Botryosphaeria were identified as Botryosphaeria dothidea, which causes ring rot. Three strains of Trichothecium were identified as Trichothecium roseum, which is responsible for the brown spots. Three strains of Alternaria were identified as Alternaria alternata, which led to the appearance of black spots on the leaves. Similarly, two strains of Pestalotiopsis were identified as Pestalotiopsis kenyana, which causes soft rot. All identified species were verified to induce harvest loquat fruit rot by validating Koch’s postulates. This is the novel report of B. dothidea, T. roseum, and P. kenyana inducing postharvest fruit rot on loquat in Yunnan, China, and globally. It is also the first evidence that A. alternata causes postharvest fruit rot and gray leaf spot on loquat in Yunnan, China. The virulence differed among species, even within isolates of the same species. Additionally, the effect of temperature on the pathogenicity of A. alternata on loquat leaves was more than humidity. These findings enhance our understanding of the fungal pathogens affecting loquat fruit in the study area and highlight the importance of effective management strategies to minimize fruit rot. Further research is needed to investigate the ecological impacts of these species and potential control measures in agricultural practices. Full article

In recent years, the cultivated area of hazelnuts in Chile has increased significantly. Along with this rapid expansion, biotic constraints that affect the optimal development of the crop have been identified. Among these, bacterial blight disease caused by Xanthomonas arboricola pv. corylina has been particularly relevant. This pathogen has a global distribution and is present in all hazelnut-producing countries. In the spring of 2023, hazelnut orchards were sampled from the Maule to Biobío Regions of Chile. The Chilean isolates recovered from hazelnut tissues showing symptoms of bacterial blight were characterized by their ability to grow on different semi-selective media, their carbohydrate utilization profiles, hypersensitivity response in tobacco plants, and biochemical tests. Additionally, the isolates were identified based on the 16S rRNA gene and multilocus sequence analysis (MLSA) on the rpoD, gyrB, and atpD genes. The results showed that the X. arboricola pv. corylina Chilean isolates differed from previously reported isolates in other geographic areas as they are capable of metabolizing sorbitol and mannitol. Using MLSA and average nucleotide identity (ANI) comparison, these isolates were grouped into four and five phylogenetic clades, respectively, representing a significant difference from what has been reported in similar international studies. Full article

The fruiting stage of soybean (Glycine max L.) is critical for determining both its yield and quality, thereby influencing global production. While some studies have provided partial explanations for the occurrence of Fusarium species on soybean seeds and pods, the fungal diversity affecting soybean pods in Sichuan Province, a major soybean cultivation region in Southwestern China, remains inadequately understood. In this study, 182 infected pods were collected from a maize–soybean relay strip intercropping system. A total of 10 distinct pod-infecting fungal genera (132 isolates) were identified, and their pathogenic potential on soybean seeds and pods was evaluated. Using morphological characteristics and DNA barcode markers, we identified 43 Fusarium isolates belonging to 8 species, including F. verticillioides, F. incarnatum, F. equiseti, F. proliferatum, F. fujikuroi, F. oxysporum, F. chlamydosporum, and F. acutatum through the analysis of the translation elongation factor gene (EF1-α) and RNA polymerases II second largest subunit (RPB2) gene. Multi-locus phylogenetic analysis, incorporating the Internal Transcribed Spacer (rDNA ITS), β-tubulin (β-tubulin), Glyceraldehyde 3-phosphate dehydrogenase (GADPH), Chitin Synthase 1 (CHS-1), Actin (ACT), Beta-tubulin II (TUB2), and Calmodulin (CAL) genes distinguished 37 isolates as 6 Colletotrichum species, including C. truncatum, C. karstii, C. cliviicola, C. plurivorum, C. boninense, and C. fructicola. Among these, F. proliferatum and C. fructicola were the most dominant species, representing 20.93% and 21.62% of the isolation frequency, respectively. Pathogenicity assays revealed significant damage from both Fusarium and Colletotrichum isolates on soybean pods and seeds, with varying isolation frequencies. Of these, F. proliferatum, F. acutatum, and F. verticillioides caused the most severe symptoms. Similarly, within Colletotrichum genus, C. fructicola was the most pathogenic, followed by C. truncatum, C. karstii, C. cliviicola, C. plurivorum, and C. boninense. Notably, F. acutatum, C. cliviicola, C. boninense, and C. fructicola were identified for the first time as pathogens of soybean pods under the maize–soybean strip intercropping system in Southwestern China. These findings highlight emerging virulent pathogens responsible for soybean pod decay and provide a valuable foundation for understanding the pathogen population during the later growth stages of soybean. Full article

The Stockholm Paradigm, a multilevel framework for studying coevolutionary interactions, it is a promising method for obtaining a globally relevant understanding of the emergence of present and past host–parasite and insect–plant interactions. This research aimed to expand the application of the Paradigm to virus–host interactions, considering that viruses are being subjected to the same evolutionary forces as any other living organism. By applying different data science techniques, we described and discussed capacity and opportunity traits for Influenza A H1N1 strains, and how they might influence the pathogen’s host repertoire evolution, and thus ranked different strains according to their emergence risk in the human population. We hope to contribute to the application of different methods for understanding disease emergence, and consequently to the development of new public health strategies for preventing (re)emerging diseases. Full article

Chrysanthemum morifolium Ramat. is a major ornamental crop that suffers from diverse fungal, bacterial, viral, and insect pests, causing significant yield and quality losses. Between 2015 and 2025, rapid progress in molecular biology, genomics, and ecological regulation has advanced both fundamental research and applied control strategies. Multi-locus sequencing, multiplex PCR, and next-generation sequencing refined the identification of fungal and bacterial pathogens, while functional studies of WRKY, MYB, and NAC transcription factors revealed key resistance modules. Hormone-mediated signaling pathways, particularly those of salicylic acid, jasmonic acid, and abscisic acid, were shown to play central roles in host defense. Despite these advances, durable genetic resistance against bacterial pathogens and broad-spectrum defense against viruses remains limited. Novel technologies, including virus-free propagation, RNA interference, and spray-induced gene silencing, have shown promising outcomes. For insect pests, studies clarified the damage and virus-vectoring roles of aphids and thrips, and resistance traits linked to trichomes, terpenoids, and lignin have been identified. Biocontrol agents such as Trichoderma spp., Bacillus spp., predatory mites, and entomopathogenic fungi have also demonstrated efficacy. Future efforts should integrate molecular breeding, genome editing, RNA-based tools, and microbiome management to achieve sustainable chrysanthemum protection. Full article

Mychonastes homosphaera MHSC24 is a green microalga newly isolated from a brackish coastal site in Korea. This study represents the first indigenous record of this species in the country. It provides a comprehensive characterization of its morphological, molecular, physiological, and biochemical characteristics. This microalga was identified through morphological observations and multilocus phylogenetic analyses. Strain MHSC24 exhibited robust growth under mesophilic temperatures (15–27 °C), moderate light intensities (88–300 μmol photons m⁻² s⁻¹), and low salinity levels (0–10 PSU). Optimal growth was observed at 27 °C, 193 μmol photons m⁻² s⁻¹, and 0 PSU. Under standard cultivation, the strain exhibited high protein levels (~54% of dry weight, DW) and accumulated substantial amounts of canthaxanthin (5.59 mg g⁻¹ DW), the predominant carotenoid in its pigment profile. Thus, MHSC24 is a promising candidate for sustainable protein- and carotenoid-based applications. Palmitic acid (11.95 mg g⁻¹ DW) and galactose (2.07 mg g⁻¹ DW) were the predominant fatty acid and monosaccharide, respectively. The physiological resilience, high protein yield, and substantial canthaxanthin accumulation of MHSC24 support its potential utilization in the functional food, feed, and nutraceutical sectors. Therefore, this study provides a basis for optimized cultivation strategies and industrial exploitation of indigenous Korean microalgae. Full article

Microbial forensics involves analyzing biological evidence to evaluate weaponized microorganisms or their toxins. This study aimed to detect and type Yersinia pestis from four simulated forensic samples—human plasma diluted in phosphate-buffered saline (#24-2), tomato juice (#24-5), grape juice (#24-8), and a surgical mask (#24-10). Notably, samples #24-10 may have contained live bacteria other than Y. pestis. A real-time polymerase chain reaction confirmed the presence of Y. pestis in all samples; however, whole-genome sequencing (WGS) coverage of the Y. pestis chromosome ranged from 0.46% to 97.1%, largely due to host DNA interference and low abundance. To address these limitations and enable strain-level identification, we designed a hybridization-based target enrichment approach focused on multilocus variable number tandem repeat analysis (MLVA). Next-generation sequencing (NGS) using whole-genome amplification revealed that the accuracy of the 25 MLVA profiles of Y. pestis for samples #24-2, #24-5, #24-8, and #24-10 was 4%, 100%, 52%, and 0%, respectively. However, all samples showed 100% accuracy with target-enriched NGS, confirming they all belong to the same strain. These findings demonstrate that a targeted enrichment strategy for MLVA loci can overcome common obstacles in microbial forensics, particularly when working with trace or degraded samples where conventional WGS proves challenging. Full article

Ilex verticillata (winterberry) is a valuable ornamental shrub increasingly threatened by leaf blight, a disease that compromises its aesthetic and economic value. While fungal pathogens like Alternaria alternata are known to cause leaf blight in horticultural crops, their role in I. verticillata and the host’s defense mechanisms have not been fully characterized. Our study investigated the pathogen-host interaction by identifying the causal agent and examining the physiological and molecular defense mechanisms of I. verticillata. Through morphological and multi-locus molecular analyses (ITS, TEF1-α, G3PDH, RPB2), A. alternata was confirmed as the primary pathogen, fulfilling Koch’s postulates. Pathogenicity assays revealed distinct disease progression stages, from necrotic lesions to tissue degradation. Transcriptomic profiling uncovered dynamic host responses, with early upregulation of pattern recognition receptors (PRRs) and transcripts encoding antioxidant enzymes (SOD, CAT), followed by downregulation of metabolic pathway genes. Phytohormone analysis highlighted intricate crosstalk, with salicylic acid (SA) peaking during mid-infection and jasmonic acid (JA) rebounding later, reflecting a coordinated defense strategy. Additionally, the oxidative stress marker malondialdehyde (MDA), an indicator of membrane lipid peroxidation, surged early, indicating membrane damage, while sustained induction of antioxidant enzymes suggested adaptive responses. The key finding was distinct phytohormone crosstalk, characterized by a mid-infection SA peak followed by a late JA rebound, alongside an early oxidative burst marked by MDA accumulation and sustained antioxidant enzyme activity. These findings provide a framework for understanding I. verticillata’s defense mechanisms and offer insights for developing targeted disease management strategies, such as resistant cultivar breeding or hormone-mediated interventions. Full article

Agrocybe chaxingu is a commercially important edible mushroom in China, valued for its rich bioactive compounds and distinctive umami flavor. In recent years, frequent disease outbreaks have severely limited production, as many pathogens spread rapidly and are difficult to control, posing a significant threat to the sustainable development of the industry. In this study, a systematic disease survey across major A. chaxingu cultivation areas in Jiangxi Province led to the isolation and identification of 17 potential fungal pathogens and 2 potential myxomycete pathogens using combined morphological characterization and multilocus phylogenetic analyses including the internal transcribed spacer (ITS) region, 28S large subunit ribosomal RNA (LSU), translation elongation factor (tef1), RNA polymerase largest subunit (rpb1), RNA polymerase second largest subunit (rpb2), Histone (H3), Beta tubulin (tub2), and 18S ribosomal RNA (18S rRNA). Among the identified diseases, white slime disease showed the highest incidence (17.3%) and was attributed to the slime mold Fuligo gyrosa, with pathogenicity confirmed according to Koch’s postulates. F. gyrosa proved highly virulent to both fruiting bodies and mycelia, enveloping host mycelium via plasmodial expansion, inhibiting growth, inducing structural rupture, and causing progressive degradation. Infection was accompanied by the deposition of characteristic stress-related pigments in the mycelium. This study provides the first detailed characterization of F. gyrosa infection dynamics in A. chaxingu mycelium. These findings provide new insights into the myxomycete pathogenesis in edible fungi and provide a foundation for the accurate diagnosis, targeted prevention, and sustainable management of diseases in A. chaxingu cultivation. Full article

The safety, genetic distinctiveness, and functional capabilities of Lactococcus sp. KTH0-1S, a strain isolated from Thai fermented shrimp (Kung-Som), were investigated to assess its potential as a next-generation probiotic and microbial cell factory. Whole-genome sequencing and multilocus sequence typing (MLST) analysis revealed that Lactococcus sp. KTH0-1S is a novel, phylogenetically distinct strain within the Lactococcus genus. Comprehensive in silico safety evaluation confirmed the absence of antimicrobial resistance genes and major virulence factors, supporting its suitability for food-grade applications. The genome encodes multiple probiotic-relevant traits, including stress tolerance (e.g., dnaK, clpP), adhesion and biofilm formation (e.g., gapA, luxS, glf2), and nutrient acquisition genes, enabling adaptation to gastrointestinal and fermentation environments. Notably, Lactococcus sp. KTH0-1S harbors a chromosomally encoded nisin Z biosynthesis gene cluster with auto-induction capability, providing a self-regulated and stable alternative to conventional plasmid-based NICE systems in Lactococcus lactis. The strain also exhibits nisin immunity, allowing tolerance to high nisin concentrations, thus supporting robust protein production. Genomic evidence and phenotypic assays confirmed a functional respiration metabolism activated by heme supplementation, enhancing biomass yield and culture stability. Furthermore, the presence of diverse CAZyme families (GHs, GTs, CEs) enables utilization of various carbohydrate substrates, including lignocellulosic and starchy agro-industrial residues. These properties collectively underscore Lactococcus sp. KTH0-1S as a safe, stable, and metabolically versatile candidate for probiotic applications and as a cost-effective, food-grade expression host for biotechnological production. Full article

Hypothyroidism is a multifactorial endocrine disorder where genetic predisposition plays a significant role. The MTHFR, MTRR, and MTR genes influence thyroid hormone regulation via homocysteine remethylation and DNA methylation. This study examined associations between hypothyroidism and polymorphisms in MTHFR (C677T–rs1801133, A1298C–rs1801131), MTRR (A66G–rs1801394), and MTR (A2756G–rs1805087) genes. Eighty-six patients with hypothyroidism and 87 healthy controls were included. Genotyping was performed using PCR-RFLP. Post hoc analysis confirmed adequate statistical power (95% for MTRR A66G, 84.6% for MTR A2756G). The study adhered to STROBE guidelines. MTHFR polymorphisms showed no significant association when considered individually. However, the MTRR A66G AA genotype was significantly more frequent in patients and conferred a markedly increased disease risk (OR: 4.373; 95% CI: 2.174–8.797; p < 0.001), while the MTR A2756G AG genotype was also more prevalent among patients and associated with higher susceptibility (OR: 2.178; 95% CI: 1.156–4.104; p = 0.008). Genotype combination analysis revealed that CT–AA (OR = 6.898; 95% CI: 1.941–24.516; p = 0.001) and AG–AA (OR = 6.892; 95% CI: 1.494–31.797; p = 0.007) conferred high risk. Certain genotypes correlated with clinical features, including hypercholesterolemia, diabetes, and cardiovascular disease. MTRR A66G and MTR A2756G polymorphisms are associated with hypothyroidism and metabolic comorbidities, both individually and in genotype combinations. These findings underscore the value of multilocus genetic models for understanding thyroid disorders and support the potential role of genetic biomarkers in personalized risk assessment and early diagnosis. GRS analysis demonstrated that each additional risk allele increased hypothyroidism risk (OR = 1.58; 95% CI: 1.18–2.10; p = 0.0018), and the total score showed moderate predictive power (AUC = 0.665; p < 0.001). Full article

Poultry and cattle are the major reservoirs of Campylobacter infection in humans. However, no information is available on Campylobacter spp. in cattle in Mongolia. Thus, this study aimed to assess their prevalence and antimicrobial resistance. Between 2019 and 2023, rectal swabs were collected from cattle on dairy farms around Ulaanbaatar city and in total, 35 Campylobacter spp., including 23 C. jejuni, 7 C. hyointestinalis, 4 C. fetus, and 1 C. lari, were isolated. Multilocus sequence typing of C. jejuni cattle isolates revealed substantial genetic diversity and identified 7 sequence types (STs) including ST61, which is known to be associated with cattle and sheep. Interestingly, the antimicrobial resistance patterns of the C. jejuni cattle isolates completely differed from those of previously reported chicken isolates. Excluding one ciprofloxacin-resistant isolate, all isolates were susceptible to tetracycline and ciprofloxacin. This is the first report on the characterization of Campylobacter spp. in cattle in Mongolia. Although no official statistics of human campylobacteriosis are currently available in Mongolia, data on Campylobacter spp. in food-producing animals represent valuable information for investigating potential sources and infection routes to humans. Full article

Yak husbandry on the Qinghai–Tibetan Plateau relies on genetically resilient sire lines, yet the paternal ancestry of the locally prominent Jiuzhi breed has never been quantified. To resolve this gap, a 690 bp fragment of the Y chromosomal SRY gene was sequenced in 117 males spanning Jiuzhi (n = 12) and five neighboring Qinghai breeds and compared with three single individual public records that represent Qinghai Plateau, Tianzhu White, and Wild yaks. Alignment, haplotype calling, diversity indices, F_ST differentiation, AMOVA, multidimensional scaling, and TCS network analysis were performed. Thirty-two haplotypes were recovered; Jiuzhi yaks possessed twelve, and six of them had private alleles. Mean A + T content was 53.8%. Haplotype diversity was highest in Qinghai Plateau, Tianzhu White and Wild yaks and lowest in Larima yaks, while Jiuzhi diversity resembled that of Huanhu. Pairwise F_ST values indicated negligible differentiation between Jiuzhi and either Qinghai Plateau or Yushu yaks (F_ST ≈ 0) but pronounced divergence from Tianzhu White and Wild yaks (F_ST ≈ 0.97–0.99). AMOVA attributed 90.7% of molecular variance to among-breed differences, and multidimensional scaling clustered Jiuzhi with Jinchuan, Yushu and Huanhu. Network topology resolved two patrilineal clades, confirming dual paternal origins for Jiuzhi yaks. These data provide the first quantitative baseline for sire selection and conservation of Jiuzhi yaks and highlight close affinities with adjacent plateau breeds. Limitations include the use of single individual public sequences for Qinghai Plateau, Tianzhu White and Wild yaks (employed solely as phylogenetic anchors) and reliance on a single Y-linked locus; broader sampling and multilocus approaches will refine within-breed estimates. Full article