Search Results (820)

Maize (Zea mays L.) is a cornerstone of food security and livestock production in Paraguay. However, its productivity and grain safety are increasingly threatened by Fusarium species because of their pathogenic capacity and ability to produce mycotoxins. In this study, symptomatic maize leaves collected from commercial fields in Pirapó, Itapúa, during the 2022 growing season were processed to isolate and characterize fungal pathogens. Three isolates displaying typical Fusarium morphology were obtained and examined through macroscopic and microscopic traits. Molecular identification was conducted using translation elongation factor 1-α 1-α (TEF) sequences, followed by phylogenetic inference using maximum likelihood and Bayesian methods. The Paraguayan isolates (PYF-MZE22-01, -02, -03) clustered with the ex-type strain Fusarium awaxy CBS139380 in a strongly supported clade, confirming species identity. This finding constitutes the first record of F. awaxy associated with maize in Paraguay, thereby expanding its known geographical distribution. Considering that members of the Fusarium fujikuroi species complex are recognized producers of regulated mycotoxins, the detection of F. awaxy raises concerns regarding its pathogenic potential and possible implications for food safety. These results underscore the importance of integrating molecular diagnostics, toxigenic profiling, and surveillance programs to monitor emerging Fusarium taxa in South American agroecosystems. Full article

This qualitative study examines the impact of societal violence on the school climate in Arab society in Israel, focusing on teachers’ perspectives. Violence is conceptualized as an extreme, intentional form of aggression aimed at causing physical, psychological, or emotional harm. In the Israeli context, Arab society, constituting about 21% of the population, experiences disproportionately high rates of violent crime, reflecting historical marginalization, structural inequality, under-policing, and sociocultural transformations. Within schools, these societal dynamics are reported to negatively affect the learning environment, including diminished teacher motivation, concerns about teaching quality, heightened perceptions of unsafety, strained parent–school relationships, and increased parental aggression. Sixteen teachers participated in semi-structured interviews. Thematic analysis of the data revealed that financial pressures, emphasis on personal honor, and erosion of family values are perceived as key drivers of violence in the community. Teachers also reported adverse effects on students’ emotional, social, and behavioral functioning, as well as academic performance. These findings underscore the urgent need for interventions that enhance school safety, provide trauma-informed teacher training, expand psychological services, and strengthen parental collaboration. Future research should include students’ and parents’ perspectives, examine geographically diverse schools, and explore cross-cultural comparisons to better understand the educational consequences of societal violence. Full article

The Lactobacillaceae family encompasses microorganisms of exceptional ecological and biotechnological importance, serving as central agents in food fermentations, health applications, and nutrient cycling across diverse environments. Despite their broad functional and phylogenetic diversity, the global distribution and ecological specialization of Lactobacillaceae are not yet fully understood. In this study, we performed a comprehensive analysis of over 2 million records from the NCBI database to survey and trace the ecological landscape of Lactobacillaceae across thousands of distinct habitats. Our results reveal that food products and animal hosts represent the primary ecological niches for members of this family. The examined taxa exhibit a broad spectrum of ecological strategies, ranging from generalists with wide environmental adaptability to specialists with strict niche preferences. Notably, our findings highlight a profound geographical and ecological sampling bias, with unclassified taxids frequent in animal gastrointestinal tracts, soils, and especially in living plant tissues—habitats identified as promising frontiers for discovering novel biodiversity. The obtained results emphasize the urgent need for expanded sampling efforts in underexplored geographic regions such as Africa, Antarctica, the Arctic, South America, and Central Asia to capture a more complete picture of Lactobacillaceae diversity. The study underscores the necessity of implementing standardized, metadata-rich data deposition practices to enable unbiased, large-scale ecological and evolutionary analyses. Ultimately, these insights not only deepen our fundamental knowledge of Lactobacillaceae diversity but also provide a strategic framework for future bioprospecting, fostering the discovery of novel strains and expanding the biotechnological potential of this influential bacterial family. Full article

Phages play a role in shaping ecosystems by controlling host abundance via cell lysis, driving host evolution via horizontal gene transfer, and promoting nutrient cycling. The genus Bradyrhizobium includes bacteria able to symbiotically nodulate the roots of soybean (Glycine max), providing the plant with a direct source of biologically fixed nitrogen. Optimizing this symbiosis can minimize the use of nitrogen fertilizers and make soybean production more sustainable. Phages targeting Bradyrhizobium may modify their hosts’ genotype, alter phenotypic traits such as symbiotic effectiveness, and mediate competition among strains for nodulation sites. Sixteen phages were isolated against B. diazoefficiens strain USDA110 and B. elkanii strains USDA94 and USDA31. Comparative analyses revealed host species-dependent diversity in morphology, host range, and genome composition, leading to the identification of three previously undescribed phage species. Remarkably, all B. elkanii phages shared a siphophage morphology and formed a single species with >97% nucleotide identity, even when isolated from farms separated by up to ~70 km, suggesting genomic stability across geographic scales. In contrast, phages isolated against B. diazoefficiens had a podophage-like morphology, exhibited greater genetic diversity, and divided into two distinct species. Although no phages were recovered against the B. japonicum strains or native Delaware Bradyrhizobium isolates tested, some Delaware Bradyrhizobium isolates showed susceptibility in a host range assay. The phage genomes demonstrated features predicting phenotypes. The phage terminase genes predicted headful packaging which promotes generalized transduction. The B. elkanii phages all carried tmRNA genes capable of rescuing stalled ribosomes, and all but one of the phages isolated against the two host species carried DNA polymerase A indicating greater phage control of genome replication. State-of-the-art structural annotation of a hypothetical gene shared by the B. diazoefficiens phages, having a mean amino acid identity of ~25% and similarity of ~35%, predicted a putative tail fiber function. Together this work expands the limited knowledge available on soybean Bradyrhizobium phage ecology and genomics. Full article

Zika virus (ZIKV) caused Zika outbreaks and continues to post threats to public health. ZIKV infection may cause congenital abnormalities during pregnancy and neurological manifestations in adults. The recurrent public health threat of Zika in various geographical areas demonstrates a need for the development of effective therapeutics. Currently, there are no approved therapies for Zika. ZIKV is a single-stranded, positive-sense RNA virus, whose genome encodes three structural proteins and seven non-structural proteins. The surface envelope (E) protein is essential for host–cell recognition and viral entry; therefore, inhibition of E-mediated viral entry is a key strategy underlying antiviral treatments. Here, molecular docking-based virtual screening was used to screen small-molecule compound libraries to identify potential ZIKV entry inhibitors. Among the compounds identified, Pyrimidine-Der1 exhibited efficient inhibition of reporter ZIKV infection. The microscale thermophoresis assay confirmed its binding with the ZIKV E protein. This compound has effective inhibition of authentic ZIKV infection in a plaque inhibition assay against R103451, PAN2016, and FLR human strains (IC₅₀: ~3–5 μM). Additionally, it efficiently inhibited ZIKV infection at viral entry and fusion steps of the virus life cycle in a time-of-addition assay. Overall, Pyrimidine-Der1 is a promising ZIKV entry inhibitor, warranting further optimization and evaluation. Full article

L. monocytogenes is a common foodborne pathogen that typically causes infections through the consumption of food contaminated with this bacterium. This study seeks to elucidate the biodiversity as well as evolutionary characteristics of L. innocua strains from different regions using comparative genomics, exploring the virulence and pathogenic potential of these strains. The findings are expected to deepen our understanding of L. innocua and provide valuable reference for public health risk assessment related to this bacterium. We performed comparative genomics on 108 food-source L. innocua isolates sourced from the USA, England, China, and Egypt to explore their biological traits and assess their pathogenic potential by predicting virulence and antibiotic resistance genes, with subsequent validation of pathogenicity through animal studies. Pan-genomic analysis showed that geographically distinct L. innocua strains possess open genomes, offering a stable genetic basis that facilitates adaptation to diverse environments. Through virulence gene prediction, we found that L. innocua strains from different regions harbor virulence genes identical to those found in pathogenic L. monocytogenes, such as inlA and inlB, as well as internal genes that may enhance the pathogenic potential of the strains. This finding demonstrates that L. innocua strains exhibit pathogenic potential. To validate their virulence, we subsequently conducted virulence assays utilizing the Galleria mellonella larval model. Following infection with L. innocua, 100% mortality was observed in a subset of Galleria mellonella larvae, albeit with a delayed time to death compared to L. monocytogenes infection. This indicates that while L. innocua exhibits attenuated virulence relative to L. monocytogenes, it retains pathogenicity. Consequently, the potential contribution of L. innocua to listeriosis cannot be overlooked in public health risk assessments. L. innocua strains isolated from food can carry virulence and resistance genes identical to those found in pathogenic L. monocytogenes strains, indicating that these L. innocua strains possess certain virulence and pathogenic potential, which was further validated through subsequent animal experimentation. This study enhances our genomic understanding of L. innocua and underscores that detecting its key virulence genes is critical for public health safety, thereby providing valuable insights into its pathogenic potential. Full article

Black tiger shrimp (Penaeus monodon) is the largest species of penaeid, being commercially cultured globally, ranking as the second most farmed species in the shrimp industry. However, with the transformation of shrimp aquaculture from semi-intensive to high-density farming, the concentration of ammonia nitrogen in the aquatic environment has increased, severely affecting the growth and survival of shrimps. To increase production efficiency, breeding new strains of shrimp with the trait of tolerance to high ammonia nitrogen is desired in the black tiger shrimp aquaculture. Previous studies have shown that glutamate dehydrogenase (GDH) and aspartate aminotransferase 2 (AST2) play important roles in the metabolism of ammonia nitrogen in crustaceans. In the present study, we conducted synteny analysis of PmGDH and PmAST2 in different species. The interactions of PmGDH with ammonium (NH₄⁺) and PmAST2 with aspartate were analyzed by docking. To develop molecule markers associated with ammonia nitrogen tolerance, SNPs of PmGDH and PmAST2 were identified by direct sequencing, genotyped by the SNaPshot technique, and characterized through genotype-phenotype association analysis by PLINK software version 1.9 in the three geographical populations, two families with different ammonia tolerance, and 120 susceptible and resistant individuals of black tiger shrimp. The results indicate that the GDH and AST2 genes are evolutionarily conserved in vertebrates, except for the black tiger shrimp, which suggests divergence in selective pressure between invertebrates and vertebrates. Notably, PmGDH may interact with NH₄⁺ via the residue Asp178 within loop 1 in the GdhA domain through a hydrogen bonding interaction, and PmAST2 may interact with aspartate via helix 1, sheet 1, loop 1, and loop 2, through both hydrogen bonding interactions and a salt bridge interaction. A total of 12 SNPs were detected in the exons of PmGDH and PmAST2. Among these candidate SNPs, the distributions of PmGDH-1227 and PmAST2-132 showed both significant differences in the genotype and allele association analysis between susceptible and resistant groups. Haplotype association analysis showed that three haplotypes exhibited significantly different distributions between susceptible and resistant groups. In conclusion, PmGDH-1227 and PmAST2-132 were associated with ammonia nitrogen tolerance, and these SNP markers are expected to contribute to marker-assisted selection (MAS) breeding programs to obtain new strains of Penaeus monodon. Full article

This study conducted a systematic investigation and identification of pathogenic fungi associated with anthracnose symptoms on economically important plants across multiple provinces in China (Beijing, Fujian, Guangdong, Guizhou, and Shaanxi). Through multi-locus phylogenetic analysis (ITS, gapdh, chs-1, act, tub2, his3, and cal) and morphological characterization of 67 strains, a total of 16 Colletotrichum species were identified, belonging to six species complexes (C. acutatum, C. boninense, C. destructivum, C. gloeosporioides, C. orchidearum, and C. spaethianum). Among these, four novel species were described: Colletotrichum aquilariae, C. crataegi, C. dongguanense, and C. flavosporum. The study also confirmed 12 known species: C. boninense, C. fioriniae, C. fructicola, C. godetiae (with C. americanum proposed as its synonym), C. gloeosporioides (with C. juglandicola, C. juglandium, and C. peakense proposed as its synonyms), C. karsti, C. nymphaeae, C. orchidearum (with C. subplurivorum proposed as its synonym), C. plurivorum, C. siamense, C. sojae, and C. spaethianum. The research revealed significant pathogen species diversity, distinct geographical distribution patterns (greatest diversity in Beijing, novel species primarily from Guangdong), and host preferences (e.g., C. gloeosporioides was the most widely distributed and dominant species on walnut). Furthermore, ten new host records were reported. The study explored correlations between pathogens and their hosts, particularly walnut, providing a crucial foundation for understanding the pathogen composition and ecology of anthracnose diseases affecting plants in China. Full article

The species Panellus stipticus presents a unique situation whereby some geographic strains are bioluminescent while others are not. This study investigates the factors affecting the bioluminescence of P. stipticus, focusing on culture media optimization, oxygen dependency, and genetic variation between luminescent and non-luminescent strains. Experiments revealed that 10% breadcrumb agar (BCA) significantly enhanced bioluminescence and colony size while supplementation with activated charcoal reduced luminescence. Comparative analysis of carbohydrate-based media showed that BCA outperformed malt extract and molasses in promoting luminescence. Oxygen was confirmed as essential for bioluminescence, with light emission ceasing rapidly under anaerobic conditions and recovering within minutes upon re-exposure to air. Phylogenetic analysis using ITS sequences distinguished luminescent and non-luminescent strains, aligning with biogeographical patterns. Dot plot synteny analysis of draft genomes of a bioluminescent (Panst LUM) and a non-bioluminescent strain (KUC8834) revealed high genomic conservation. However, absence of key bioluminescence genes in non-luminescent strains explains their lack of light emission. Protein sequence comparisons of core enzymes—LUZ, HISP, and H3H—showed functional similarity with Mycenoid lineage species. These findings deepen our understanding of fungal bioluminescence and its genetic and environmental determinants. Full article

Infections caused by avian orthoreovirus represent an emerging problem with a major impact on the global poultry industry, especially in the intensive rearing of broilers. This article addresses, in a complex manner, the etiology of some clinical syndromes of interest in poultry farming: malabsorption syndrome and arthritis/tenosynovitis syndrome. Data are presented, starting from the development and physiology of the digestive tract in broiler chickens in the post-hatch period, epidemiological data, clinical signs, morphopathological changes in the intestine, and diagnostic methods in orthoreovirus infections. The development of the digestive tract is influenced by factors such as diet, digestive enzymes, intestinal pH, and intestinal microbiome/virome. Avian orthoreoviruses, belonging to the Reoviridae family, are double-stranded RNA viruses with multiple tropism. Phylogenetic analysis revealed the existence of at least six major genotypes, with a heterogeneous geographical distribution and genetic diversity that complicates control measures with vaccination. Characterization of the intestinal virome of broilers highlights many other enteric viruses, in addition to reoviruses, with pathogenic potential in triggering malabsorption syndrome. Thus, we can state that the etiology of malabsorption syndrome is not unitary, with the association of several viruses with intestinal tropism aggravating the clinical signs. The article describes viral identification methods, including classical techniques and advanced next-generation sequencing (NGS) approaches, used to characterize the intestinal virome and emerging pathogens. Finally, for prophylaxis, autogenous vaccines adapted to local circulating strains are recommended. Frequent genetic recombinations and high antigenic variation require continuous monitoring and constant adaptation of immunization schedules to control the disease. Full article

In the context of the global growth of the collaborative economy, Airbnb has established itself as one of the most influential players in the transformation of the tourist accommodation market, especially in the reconfiguration of urban tourist accommodation. This article examines empirically and critically how this platform operates in Buenos Aires, the most visited city in Argentina and one of the main tourist hubs in South America. Based on a database of 17,249 active listings, the price formation of accommodations is analyzed using a comparative methodological approach between a general linear model (GLM) and a geographically weighted regression (GWR) model. While the GLM allows for capturing general patterns, the GWR reveals significant territorial differences, offering a detailed reading of the spatial behavior of prices in the city. The results show that variables such as the capacity of the accommodation, its type (full house), the host’s condition, the users’ ratings and the proximity to strategic points such as the subway or Plaza de Mayo have a significant influence on prices. In addition, it is shown that the influence of these variables varies by neighborhood, confirming that the pricing logic in Airbnb is deeply territorialized. This study not only provides novel empirical evidence for a Latin American city that has been little explored in the international literature, but also offers useful tools for hosts, urban planners and public decision makers. Its main contribution lies in showing that prices respond not only to accommodation attributes, but also to broader spatial inequalities, opening the debate on the effects of Airbnb on housing access and urban management in cities with strained real estate markets. By shedding light on these territorial asymmetries, the study offers valuable insights for public policy and urban governance and contributes directly to the achievement of Sustainable Cities and Communities (SDG 11), while also supporting Industry, Innovation and Infrastructure (SDG 9) and Reduced Inequalities (SDG 10), by providing practical knowledge that fosters more equitable and sustainable urban development. Full article

Clostridioides difficile was first identified in 1935 and subsequently emerged over the next several decades as the predominant bacterial cause of healthcare-associated gastrointestinal infections, placing a significant burden on healthcare systems worldwide. A major driver of the rapid rise in the incidence of C. difficile infection (CDI) was the emergence and spread of a hypervirulent strain, which became known as PCR ribotype 027 (RT027). The C. difficile RT027 strain produced not just the typical toxin A and toxin B virulence factors but also expressed a third toxin called binary toxin that enhanced pathogenicity. Interestingly, the C. difficile RT027 strain apparently emerged at least twice in geographically distinct areas. The two lineages can be differentiated by their resistance or susceptibility to fluoroquinolones. Other ribotypes of C. difficile that also express binary toxin have emerged recently, some of which are highly related genetically to RT027. The aim of this study is to integrate genomic data and published literature to clarify the emergence, divergence, and apparent decline of C. difficile RT027. Full article

Bacillus anthracis is the etiological agent of the zoonotic disease anthrax. The pathogen has colonized many regions of all inhabited continents. Increasing evidence points to a strong contribution of anthropogenic activities (trade) in this almost global spread. This article contributes further genomic data from 21 B. anthracis strains, including 19 isolated in Germany, aiming to support and detail the human role in anthrax dispersal. The newly sequenced genomes belong to the B. anthracis lineage predominant in China. This lineage is remarkable because of its phylogenetic structure. A polytomy with nine branches radiating from a central node was identified by whole-genome single-nucleotide polymorphism (wgSNP) analysis. Strains from Germany populate two among the nine branches. Detailed analysis of the polytomy indicates that it most likely emerged in China. We propose that the polytomy is the result of the import of contaminated animal products in a limited spatiotemporal frame, followed by the distribution of these products to different locations within China, where new B. anthracis lineages then became independently established. Currently available data point to Bengal as a likely geographic source of the original contamination, and the history of trade exchanges between Bengal and China agrees with the early fifteenth century as a likely time period. The subsequent exports to Germany would have occurred during the 19th century according to German trade history. Notably, Germany has been experiencing localized anthrax outbreaks from this trade heritage up into the 21st century. Full article

The Lake Velence watershed faces increasing challenges driven by local and global factors, including the impacts of climate change, energy resource limitations, and greenhouse gas emissions. These issues, particularly acute in water management, are exacerbated by prolonged droughts, growing population pressures, and shifting land use patterns. Such dynamics strain the region’s scarce water resources, negatively affecting the environment, tourism, recreation, agriculture, and economic prospects. Nadap, a hilly settlement within the watershed, experiences frequent flooding and poor water retention, yet it also boasts the highest solar panel capacity per property in Hungary. This research addresses these interconnected challenges by designing a solar-hydrodynamic network comprising four multi-purpose water reservoirs. By leveraging the settlement’s solar capacity and geographical features, the reservoirs provide numerous benefits to local stakeholders and extend their impact far beyond their borders. These include stormwater management with flash flood mitigation, seasonal green energy storage, water security for agriculture and irrigation, wildlife conservation, recreational opportunities, carbon-smart winery developments, and the creation of sustainable blue-green settlements. Reservoir locations and dimensions were determined by analyzing geographical characteristics, stormwater volume, energy demand, solar panel performance, and rainfall data. The hydrodynamic system, modeled in Matlab, was optimized to ensure efficient water usage for irrigation, animal hydration, and other needs while minimizing evaporation losses and carbon emissions. This research presents a design framework for low-carbon and cost-effective solutions that address water management and energy storage, promoting environmental, social, and economic sustainability. The multi-purpose use of retained rainwater solves various existing problems/challenges, strengthens a community’s self-sustainability, and fosters regional growth. This integrated approach can serve as a model for other municipalities and for developing cost-effective inter-settlement and cross-catchment solutions, with a short payback period, facing similar challenges. Full article

Aedes (Stegomyia) albopictus (Skuse), a mosquito vector with increasing capacity to transmit human arboviral infections worldwide, naturally harbors the intracellular bacterium Wolbachia spp. This relationship has been observed in native mosquito populations of Ae. albopictus around the world and, more recently, in Mérida, Yucatán, México (abbreviated hereafter as MID). This study provides additional evidence confirming the presence of Wolbachia A (wAlbA) and B (wAlbB) strains in field-collected Ae. albopictus of Mérida, based on wsp gene DNA sequencing analyses of 14 positive PCR samples. Maximum likelihood (ML) analyses of the wsp gene showed high nucleotide sequence homology between Wolbachia from Merida and the globally reported strains A and B, suggesting that these two Wolbachia strains have remained stable in Ae. albopictus over time, regardless of the geographical area. To the best of our knowledge, this is the first report of Wolbachia gene sequencing in native populations of Ae. albopictus in Yucatán, Mexico. Currently many Aedes mosquitoes (e.g., Ae. aegypti) harboring intracellular Wolbachia B bacteria are being released as part of arbovirus and mosquito control programs in Yucatan and globally. Understanding the presence and stability of Wolbachia strains across different Aedes host backgrounds is crucial to ensuring the long-term effectiveness of biological interventions aimed at controlling mosquito populations and arbovirus transmission in endemic areas. Full article