Climate change and the emergence of fungal pathogens

Allochthonous zoonotic sporotrichosis in the Brazilian Central-West: diagnostic challenges in a nonendemic area

Sporotrichosis, a neglected zoonotic fungal infection, is becoming increasingly prevalent in Brazil, with cats being the primary source of human transmission. This report details the first documented case of zoonotic human sporotrichosis in Mato Grosso State, a non-endemic area; the infection was acquired from an animal in an endemic area. The patient developed a subcutaneous ulcerative lesion following contact with a cat from Minas Gerais State, a known disease hotspot. Initially misdiagnosed, the infection was later confirmed as Sporothrix brasiliensis after fungal culture and molecular analysis. The patient was successfully treated with itraconazole. This case highlights the importance of considering sporotrichosis in the differential diagnosis, even in non-endemic areas, due to the risk of zoonotic transmission. It also emphasizes the need for a One Health approach to improve surveillance, diagnostic accuracy, and management of emerging fungal diseases in endemic and expanding areas.

High azole non-wild type rates and nosocomial microsatellite typing aggregation of Wickerhamomyces anomalus in China according to a 12-year multicenter surveillance study

OBJECTIVES

To investigate the epidemiology and molecular typing of 307 clinical Wickerhamomyces anomalus isolates collected in China.

METHODS

A total of 307 W. anomalus isolates were collected from CHIF-NET, a surveillance network with nationwide coverage, from 2009 to 2021. Antifungal susceptibility of all W. anomalus isolates were tested by broth microdilution according to CLSI methods. Genotyping of all isolates was performed using a panel of polymorphic microsatellite markers.

RESULTS

The number of W. anomalus isolates was highest in Northeast China, with 121 strains, accounting for 4.6% of the total Candida spp. isolates in the region. Newborns emerged as the primary community of infection, with 84 isolates (12.7% of all Candida spp. in the newborn group). Most W. anomalus isolates were recovered from blood samples (249 isolates). The isolates were found to exhibit notable ratios of non-wild type to fluconazole and voriconazole (48.5% and 34.5%). A total of 118 microsatellite-based types were identified among a set of 309 isolates that included the 307 clinical isolates along with reference strains ATCC 8168 and CICC 32553. This analysis revealed potential nosocomial outbreaks.

CONCLUSIONS

Our research is the largest investigation of W. anomalus drug susceptibility thus far, providing foundational data that could contribute to future establishment of resistance breakpoints and enhancing epidemiological surveillance capabilities. Our study suggests the importance of nosocomial surveillance and drug resistance management for W. anomalus.

A relationship between body size and the gut microbiome suggests a conservation strategy

A key goal of conservation is to protect the biodiversity of wild species to support their continued evolution and survival. Conservation practice has long been guided by genetic, ecological, and demographic indicators of risk. Cope's rule suggests that species tend to evolve larger body sizes over time. Here, we provide strong evidence to support the inclusion of body size when formulating wildlife conservation strategies. The gut microbiome can mirror the physiological and environmental adaptation status of the host. This study established a connection between body size and the gut microbiome in the Felidae family using 70 fecal samples collected from 18 individuals through metagenomic data analysis and mining metagenome-assembled genomes (MAGs). Two enterotypes were identified in the Felidae gut: Bacteroides and Clostridium. Medium-sized felids predominantly harbored Clostridium, associated with pathogenicity, whereas large and small felids harbored both beneficial Bacteroides and pathogenic Clostridium. Species that evolved larger body sizes over time exhibited distinct changes in gut microbial communities, such as enhanced nutrient extraction and metabolic capabilities. Larger felids exhibited a more diverse, stable gut microbiome engaged in metabolic processes and extensive host interactions, indicating an evolved functional role in various biological processes. Conversely, that of smaller felids is less diverse, with more viruses and pathogenic elements primarily involved in chemical synthesis. These findings provide essential insights for developing conservation strategies that consider the nutritional needs of different-sized feline species, control the transmission of pathogens, and allocate resources based on their unique gut microbiome characteristics.IMPORTANCEBody size is a fundamental trait that varies greatly among taxa and has important implications for life history and ecology. Cope's rule suggests that species tend to evolve larger body sizes over time. However, its correlation to body size evolution remains unclear. This study aimed to establish a connection between body size and the gut microbiome in the Felidae family through metagenomic data analysis. Our results support Cope's rule, illustrating that increased body size correlates with shifts in the gut microbiome, enhancing survival and adaptability.

Advanced droplet microfluidic platform for high-throughput screening of industrial fungi

Industrial fungi are pivotal candidates for the production of a diverse array of bioproducts. To enhance their productivity, these strains are frequently subjected to genetic modifications. Following transformation, the selection of optimal production strains is critical; however, traditional screening methods often suffer from limitations in throughput and sensitivity. This article explores the transformative potential of Droplet Microfluidic Technology (DMFS) for high-throughput screening of industrial fungi. DMFS enables real-time monitoring and precise single-cell analysis by encapsulating individual fungal spores or cells within droplets, ranging from picoliters to nanoliters, functioning as isolated microreactors. This technology effectively addresses the challenges posed by conventional methods, such as agar plate assays and fluorescence-activated cell sorting. Key advancements discussed include microfluidic chip fabrication, droplet generation and regulation techniques, and multimodal signal detection methods-encompassing fluorescence, Raman spectroscopy, and mass spectrometry. Notably, strategies to mitigate droplet breakage in filamentous fungi, including physical constraints, bionic core-shell hydrogels, and genetic engineering approaches, are analyzed to prolong stable culture times. Future developments will likely emphasize interdisciplinary applications, including automation driven by artificial intelligence and label-free detection methods. We anticipate that this review will catalyze further research into high-quality industrial fungi, thereby promoting sustainable biomanufacturing through enhanced throughput, cost-effectiveness, and scalability.

Frequency of mycological diagnosis in a clinical laboratory in the city of Pelotas, south of Brazil, during the three-year period (2020-2023)

The increasing prevalence of immunosuppressive diseases, the increase in the elderly population, and globalization have led to the urgent need for research on the epidemiology and prevalence of fungi that cause mycoses in Brazil and worldwide. This is especially important, in the case of Brazil, for the South region, which currently lacks updated data on the subject. To this end, the objective was to investigate fungi diagnosed in mycoses by a laboratory in the city of Pelotas, South of Brazil. An observational and analytical survey was conducted for three years to analyze fungal diagnoses in the laboratory. Statistical analyses were performed by using SPPS and Joinpoint software. In total, 1220 fungal diagnoses were conducted, with 169 (13,8%) in 2020, 399 (32,7%) in 2021, 470 (38,5%) in 2022, and 182 (15,0%) in 2023, showing an increase in diagnoses over the years, with women seeking more diagnoses than men. Spring and summer were the seasons with the most diagnoses, and cutaneous and opportunistic mycoses were the most prevalent. Dermatophytes were the most diagnosed, followed by Candida spp. However, there was an increase in non-dermatophyte fungi diagnosed for onychomycosis. Therefore, despite the increase in the number of diagnoses over the years, it is important and necessary to establish standards for diagnosis in Brazil and worldwide for fungal diseases, especially the mandatory notification of serious mycoses. This will raise awareness in the healthcare sector and the public about the importance of diagnosing and treating fungal infections, which cause many fatalities every day.

Novel Disk diffusion Assay for Filamentous Fungi Susceptibility to antifungals (DAFFS)

Filamentous fungi are recognized as significant human pathogens, particularly in immunocompromised populations. The rise in antifungal resistance and geographical expansion due to environmental changes, including climate change, further complicates treatment efforts. Existing antifungal susceptibility testing methods often face challenges when applied to filamentous fungi. Variability in results, extended incubation times, and difficulties in standardization can compromise broth dilution and disk diffusion assays. Here, we present an improved method, the Disk diffusion Assay for Filamentous Fungi Susceptibility to antifungals (DAFFS), designed to overcome current challenges in antifungal susceptibility testing for filamentous fungi. DAFFS integrates optimized elements from standard methods for more efficient screening of filamentous fungi for susceptibility to established and novel antifungals. This approach offers a streamlined, reliable alternative for assessing fungal drug susceptibility by addressing the limitations of current testing methods.

Allergic Fungal Rhinosinusitis Diagnosis, Management, Associated Conditions, Pathophysiology, and Future Directions: Summary of a Multidisciplinary Workshop

Allergic fungal rhinosinusitis (AFRS) is a unique endotype of chronic rhinosinusitis with nasal polyps (CRSwNP). Despite high recurrence rates and often more severe presenting signs compared with other subtypes of CRSwNP, research dedicated to AFRS has been lacking. Diagnostic criteria are outdated, the mechanistic relationship of AFRS to other associated diseases is unclear, and the pathophysiology of disease and risk factors for recurrence have not been well studied. In December 2023, a multidisciplinary group of rhinologists, otolaryngologists, pulmonologists, allergists, immunologists, scientists, and infectious disease experts met at the National Institute of Health to discuss unmet needs for future AFRS research and care, including patient management, diagnostic criteria, severity, pathophysiology, and related conditions. A summary of these clinical and associated research discussions is included below.

Detection and taxonomic identification of emerging pathogenic yeasts in surface waters from Lagoon Systems in Rio de Janeiro, Brazil

This study aimed to detect and identify emerging pathogenic yeasts in surface waters from two Lagoon Systems in Rio de Janeiro, Brazil, by polyphasic taxonomy. The monitoring of potentially pathogenic fungi in aquatic environments, especially in regions impacted by human actions, is highlighted in this study as one of the axes of the One Health approach. Water samples were collected, and after isolation, fungi were identified by polyphasic taxonomy, including MALDI-TOF-MS, which is also used for bacteria identification. Our results describe the physicochemical parameters of the surface water of these lagoons and reveal a significant diversity of yeast species, some of which are known to exhibit pathogenic potential and resistance to common antifungal treatments, as well as bacteria with resistance profiles to several currently used antibiotics. We conclude that Jacarepaguá Lagoon is the most impacted compared to Piratininga Lagoon; however, we highlight the urgent need for targeted interventions to mitigate pollution in both Lagoons, reinforcing the value of long-term surveillance in both ecosystems. We believe that monitoring emerging species is as critical as analyzing traditional water quality parameters. Early detection of resistant or invasive pathogens in aquatic ecosystems can prevent disease outbreaks, protect biodiversity, and mitigate public health risks, preventing loss of life, and optimizing public healthcare system expenditures.

Detection of Histoplasma capsulatum in Bats from the Brazilian Western Amazon

Histoplasma capsulatum is a saprophytic dimorphic fungus that causes histoplasmosis, a systemic infectious disease of relevance to public health. Bats can be important agents in the epidemiological cycle of the disease since they act as reservoirs of microorganisms. The aim of this study was to detect Histoplasma capsulatum in the lung tissue of bats captured in urban forest fragments in the municipality of Rio Branco, Acre, in the Western Amazon. Twenty-two bat species were captured from five urban forest fragments. The samples taken were subjected to histopathological, mycological, and molecular analysis. Among the 96 animals analyzed, the fungus was detected in 32.29% (31/96). This was the first study to detect the pathogen in bats in the Western Amazon. It is also the first record of the fungus being detected in six bat species. The state of Acre is located in a region with a rich diversity of bats. Furthermore, this area is constantly suffering from climatic and environmental changes that can favor the emergence and re-emergence of diseases. Thus, active epidemiological research and surveillance of neglected fungal infections are essential, especially considering the concept of One Health.

Fungi as an emerging waterborne health concern: impact of treated wastewater discharge versus aerosolization

The discharge of treated wastewater effluents into river-fed irrigation canals results in a de facto form of water reuse. Waterborne fungal populations in such environments pose a unique human health concern given that opportunistic fungal pathogens can be proliferated during spray irrigation of crops. In the present study, we consider two different routes (effluent discharge versus bioaerosols) through which wastewater treatment plants (WWTPs) can impact the presence and abundance of fungal communities in irrigation canals of the Rio Grande river basin in New Mexico. Site A was selected to investigate the influence of effluent discharge from a WWTP on waterborne fungal communities in a receiving irrigation canal. Site B represented an irrigation canal that was directly adjacent to a WWTP but that receives no effluent discharge (to exemplify bioaerosolization exclusively). Sampling dates were chosen to capture variations in weather and stream flow conditions at each of the two sites. Results indicated that treated wastewater discharged into the canal had a distinct impact on fungal community composition, especially under low wind and flow conditions. When stream flow was highest, variations along the canal at Site A were minimal. The highest occurrence of pathogen-associated genera was observed at Site B under high wind conditions with an average relative abundance of 20.9 ± 13.1% (peak of 39.3%) and was attributable to bioaerosol emissions from the WWTP and a nearby livestock facility. Such genera included Alternaria, Cladosporium, and Cryptococcus. These findings suggest that although treated effluent discharge can directly impact irrigation canal fungal community composition, bioaerosols likely have a larger overall effect on the spread of potential fungal pathogens.

Impact of climate change on the potential global prevalence of Macrophomina phaseolina (Tassi) Goid. under several climatological scenarios

Introduction

Climate change forms one of the most dangerous problems that disturb the earth today. It not only devastates the environment but also affects the biodiversity of living organisms, including fungi. Macrophomina phaseolina (Tassi) Goid. is one of the most pervasive and destructive soil-borne fungus that threatens food security, so predicting its current and future distribution will aid in following its emergence in new regions and taking precautionary measures to control it.

Methods

Throughout this work, there are about 324 records of M. phaseolina were used to model its global prevalence using 19 environmental covariates under several climate change scenarios for analysis. Maximum Entropy (MaxEnt) model was used to predict the spatial distribution of this fungus throughout the world while algorithms of DIVA-GIS were chosen to confirm the predicted model.

Results

Based on the Jackknife test, minimum temperature of coldest month (bio_6) represented the most effective bioclimatological parameter to fungus distribution with a 52.5% contribution. Two representative concentration pathways (RCPs) 2.6 and 8.5 of global climate model (GCM) code MG, were used to forecast the global spreading of the fungus in 2050 and 2070. The area under curve (AUC) and true skill statistics (TSS) were assigned to evaluate the resulted models with values equal to 0.902 ± 0.009 and 0.8, respectively. These values indicated a satisfactory significant correlation between the models and the ecology of the fungus. Two-dimensional niche analysis illustrated that the fungus could adapt to a wide range of temperatures (9 °C to 28 °C), and its annual rainfall ranges from 0 mm to 2000 mm. In the future, Africa will become the low habitat suitability for the fungus while Europe will become a good place for its distribution.

Discussion

The MaxEnt model is potentially useful for predicting the future distribution of M. phaseolina under changing climate, but the results need further intensive evaluation including more ecological parameters other than bioclimatological data.

Developing the trehalose biosynthesis pathway as an antifungal drug target

Invasive fungal infections are responsible for millions of deaths worldwide each year. Therefore, focusing on innovative approaches to developing therapeutics that target fungal pathogens is critical. Here, we discuss targeting the fungal trehalose biosynthesis pathway with antifungal therapeutics, which may lead to the improvement of human health globally, especially as fungal pathogens continue to emerge due to fluctuations in the climate.

Transmission dynamics of multidrug resistant Klebsiella pneumoniae from an Indian hospital

OBJECT

The dissemination of Klebsiella pneumoniae is becoming a major concern, as this organism is responsible for a significant proportion of hospital acquired infections. Due to complexity of this organism adequate knowledge on the epidemiology and infection control practices associated with the dissemination is highly required. Therefore, this study designed to include consecutive samples from environment and patients to assess the similarity pattern among isolates from different sources.

METHODOLOGY

We included patients with hospital acquired infections with K. pneumonaie and environment isolates. To obtain the complete sequence forty-eight isolates were sequenced on Illumina MiSeq 250 2 × 250 bp paired end (Illumina, USA) and Nanopore (Oxford). These includes 30 BSI cases, 13 environment and 5 from water. Assembly of good quality reads were prepared using Unicycler. AMR gene detection was done using Resfinder of Abricate and sequence similarity was observed by SNP based phylogenetic analysis.

RESULTS

The most common sequence type of organism among all was ST 231 and ST 395. ST 29 was common between water and clinical isolates. Average (range) number of AMR genes present in clinical isolates were 16 (3-24). The antimicrobial genes belong to 41 classes and fosA was highly prevalent. The frequency of blaNDM was present 55.4 % (27/48) and blaOXA in 61.6 % (30/48). The strain ST 395 and ST 16 carried highest no. of replicons n = 10 and n = 9. The predominant plasmid replicon Col440I (N = 58) followed by IncFII_1_pKP91 (N = 34) and ColRNAI (N = 29). The phylogenetic analysis showed high similarity between clinical and environmental samples.

CONCLUSION

This study concludes that environment play essential role in disseminating the infectious strains of organism resulting in increased rates of hospital acquired infections. Therefore, there is an imperative necessity for implementing infection control practices to prevent the spread of infectious diseases.

Plant-Derived UDP-Glycosyltransferases for Glycosylation-Mediated Detoxification of Deoxynivalenol: Enzyme Discovery, Characterization, and In Vivo Resistance Assessment

Fungal infections of crops pose a threat to global agriculture. Fungi of the genus Fusarium cause widespread diseases in cereal crops. Fusarium graminearum reduces yields and produces harmful mycotoxins such as deoxynivalenol (DON). Plants mitigate DON toxicity through glucose conjugation mediated by UDP-glycosyltransferases (UGTs), forming deoxynivalenol-3-O-glucoside (DON-3-Glc). Few such UGTs have been identified, predominantly from Fusarium-susceptible crops. Given that the presence of this activity in diverse plants and across broader UGT subfamilies and groups was underexplored, we screened a library of 380 recombinant plant UGTs and identified and characterized eight novel enzymes glycosylating DON in vitro. Among these, ZjUGT from Ziziphus jujuba stood out with the highest activity, showing an apparent kcat of 0.93 s-1 and kcat/Km of 2450 M-1 s-1. Interestingly, four enzymes produced primarily a novel, still uncharacterized glucoside. Furthermore, we evaluated the in vivo resistance provided by these UGTs when expressed in a DON-sensitive yeast strain. At least six of the novel UGTs conferred some level of resistance, allowing growth at concentrations of up to 120 mg/L of DON. This study contributes to potential strategies to enhance DON resistance in cereal crops in the future.

Classification of Mycena and Marasmius Species Using Deep Learning Models: An Ecological and Taxonomic Approach

Fungi play a critical role in ecosystems, contributing to biodiversity and providing economic and biotechnological value. In this study, we developed a novel deep learning-based framework for the classification of seven macrofungi species from the genera Mycena and Marasmius, leveraging their unique ecological and morphological characteristics. The proposed approach integrates a custom convolutional neural network (CNN) with a self-organizing map (SOM) adapted for supervised learning and a Kolmogorov-Arnold Network (KAN) layer to enhance classification performance. The experimental results demonstrate significant improvements in classification metrics when using the CNN-SOM and CNN-KAN architectures. Additionally, advanced pretrained models such as MaxViT-S and ResNetV2-50 achieved high accuracy rates, with MaxViT-S achieving 98.9% accuracy. Statistical analyses using the chi-square test confirmed the reliability of the results, emphasizing the importance of validating evaluation metrics statistically. This research represents the first application of SOM in fungal classification and highlights the potential of deep learning in advancing fungal taxonomy. Future work will focus on optimizing the KAN architecture and expanding the dataset to include more fungal classes, further enhancing classification accuracy and ecological understanding.

Inhibitors of trehalose-6-phosphate synthase activity in fungal pathogens compromise thermal tolerance pathways

Infections caused by fungal pathogens such as Candida and Cryptococcus are associated with high mortality rates, partly due to limitations in the current antifungal arsenal. This highlights the need for antifungal drug targets with novel mechanisms of action. The trehalose biosynthesis pathway is a promising antifungal drug target because trehalose biosynthesis is essential for virulence in Cryptococcus neoformans and Candida albicans and is also a mediator of fungal stress responses, such as thermotolerance. To exploit its untapped antifungal potentials, we screened the St. Jude 3-point pharmacophore library to identify small molecule inhibitors of the first enzyme in the trehalose biosynthesis pathway, trehalose-6-phosphate synthase (Tps1). Structure-guided optimization of a potent hit, SJ6675, yielded a water-soluble inhibitor named 4456dh. Employing biochemical, structural and cell-based assays, we demonstrate that 4456dh inhibits Tps1 enzymatic activity, suppresses trehalose synthesis and exerts a fungicidal effect. Notably, the structure of Tps1 in complex with 4456 reveals that 4456 occupies the substrate binding pocket. Importantly, 4456dh renders normally thermotolerant fungal pathogens unable to survive at elevated temperatures, which is critical as we investigate the emergence of fungi from the environment due to a warming climate. Overall, this work develops the water-soluble 4456dh as an early-stage antifungal drug that has a distinct mechanism of action compared to existing clinical antifungals.

Sustainable Management of Major Fungal Phytopathogens in Sorghum (Sorghum bicolor L.) for Food Security: A Comprehensive Review

Sorghum (Sorghum bicolor L.) is a globally important energy and food crop that is becoming increasingly integral to food security and the environment. However, its production is significantly hampered by various fungal phytopathogens that affect its yield and quality. This review aimed to provide a comprehensive overview of the major fungal phytopathogens affecting sorghum, their impact, current management strategies, and potential future directions. The major diseases covered include anthracnose, grain mold complex, charcoal rot, downy mildew, and rust, with an emphasis on their pathogenesis, symptomatology, and overall economic, social, and environmental impacts. From the initial use of fungicides to the shift to biocontrol, crop rotation, intercropping, and modern tactics of breeding resistant cultivars against mentioned diseases are discussed. In addition, this review explores the future of disease management, with a particular focus on the role of technology, including digital agriculture, predictive modeling, remote sensing, and IoT devices, in early warning, detection, and disease management. It also provide key policy recommendations to support farmers and advance research on disease management, thus emphasizing the need for increased investment in research, strengthening extension services, facilitating access to necessary inputs, and implementing effective regulatory policies. The review concluded that although fungal phytopathogens pose significant challenges, a combined effort of technology, research, innovative disease management, and effective policies can significantly mitigate these issues, enhance the resilience of sorghum production to facilitate global food security issues.

Climate Change and Medical Mycology

This review explores how climate change influences fungal disease dynamics, focusing on emergence of new fungal pathogens, increased antifungal resistance, expanding geographic ranges of fungal pathogens, and heightened host susceptibility. Rising temperatures and altered precipitation patterns enhance fungal growth and resistance mechanisms, complicating treatment efforts. Climate-driven geographic shifts are expanding the range of diseases like Valley fever, histoplasmosis, and blastomycosis. Additionally, natural disasters exacerbated by climate change increase exposure to fungal pathogens through environmental disruptions and trauma. Many of those impacts affect primarily those already disadvantaged by social determinants of health putting them at increased risk for fungal diseases.

Characterization of susceptibility patterns and adaptability of the newly emerged Candida auris

The emergence of Candida auris has caused a major concern in the public health worldwide. This novel fungus is characterized by its multidrug resistance profile, ability to thrive in harsh and stressful conditions, as well as high temperatures and salt concentrations, persistence on hospital surfaces, causing nosocomial infections and outbreaks, and unique fitness properties. Here, we study the antifungal susceptibility patterns, thermotolerance, and halotolerance of 15 putative C. auris clinical isolates from Inkosi Albert Academic Hospital, Durban, South Africa. Five of the C. auris isolates showed resistance to all three antifungals (fluconazole, amphotericin B, and micafungin) and were selected for characterization of their adaptability mechanisms. Four of the tested multidrug-resistant C. auris isolates (C. auris strain F25, C. auris strain F276, C. auris F283, and C. auris M153) showed good growth when exposed to high temperature (42 °C) and salinity (10% NaCl) conditions whereas one isolate (C. auris F65) showed moderate growth under these conditions. Candida parapsilosis showed poor growth whereas C. albicans no growth under these conditions. The five C. auris strains were positive for all the adaptive features.

Dematiaceous Molds

Dematiaceous molds are darkly pigmented environmental molds found worldwide, especially prevalent in tropical and subtropical regions. Common genera include Bipolaris, Cladophialophora, Exophiala, and Alternaria. They cause disease in both immunocompetent and immunocompromised individuals, presenting as cutaneous infections, allergic sinusitis, pneumonia, and, rarely, disseminated infections. Contaminated medical products have also led to fungal meningitis outbreaks. Treatment typically involves itraconazole, voriconazole, or posaconazole, along with source control and reduction in immunosuppression, if possible. Newer antifungals may have a role in treatment. Mortality is high in disseminated disease, especially with Lomentospora prolificans in immunocompromised individuals, prompting global efforts to improve diagnostics and treatments.

Integrated multiomics approach and pathological analyses provide new insights into hepatic injury and metabolic alterations in Saanen goats after dietary exposure to aflatoxin B1

Exploring the toxicity and metabolic mechanisms of aflatoxin B1 (AFB1) in ruminants can help to develop strategies to prevent or reduce the transfer of the toxin and its metabolites to milk and meat. This study aimed to explore the effects of 3 concentrations of dietary AFB1 (0, 50, and 500 μg/kg) on hepatic injury and metabolism in Saanen goats via histological examination, western blot analysis, as well as integrated multiomics techniques. Eighteen Saanen goats were assigned to 1 of 3 treatments and the AFB1 challenge lasted for 14 d. Results showed that the liver tissue was enlarged and the relative organ index of the liver was linearly increased with elevated AFB1 levels. The hepatocyte apoptosis rate was significantly increased after AFB1 exposure, and the western blotting results revealed that both the external apoptotic pathway and mitochondrial-mediated intrinsic apoptotic pathway might be involved in AFB1-induced hepatocyte apoptosis. We identified 251, 269, and 154 significant differentially expressed genes (DEG) and 340, 596, and 127 significant differential metabolites in comparisons between the control (CON; 0 μg/kg) and low-dose (LO; 50 μg/kg) groups, the CON and high-dose (HI; 500 μg/kg) groups, and the LO and HI groups, respectively. The DEG annotated were mainly involved in the cell part, cell, single-organism process, cellular process, binding, and other functional categories. The identified metabolites primarily belonged to glycerophospholipids, prenol lipids, carboxylic acids, and derivatives. Integrative analysis of transcriptomics and metabolomics revealed that glycerophospholipids metabolism and choline metabolism in cancer were the most affected pathways related to AFB1 exposure. The identified differential metabolites, DEG, and pathways might have played a crucial role in the hepatic injury induced by AFB1 in goats.

Spontaneous and environment induced genomic alterations in yeast model

While genomic alterations are fundamental to biological evolution, enabling adaptation and diversity, they can also result in detrimental outcomes, such as the development of genetic diseases including cancer. The budding yeast Saccharomyces cerevisiae serves as an exemplary model for investigating the mechanisms behind various genomic alterations, including point mutations, chromosomal rearrangements, and whole-chromosome aneuploidy. In this review, we highlight the application of genetic screening systems to assess the mutagenic effects of physical and chemical agents efficiently. Additionally, we discuss the utilization of high-throughput sequencing technologies to uncover comprehensive genomic alterations and rare genetic events. We provide a detailed summary of the features of genomic alterations and discuss the genetic mechanisms driving these changes under both spontaneous and stress-induced conditions. Given the high conservation of DNA replication and repair machinery across different organisms, the insights gained from studies on yeast offer valuable perspectives for understanding the delicate balance between genome plasticity and integrity in other species.

Recognizing the Importance of Public Health Mycology

Fungal diseases are an emerging global public health concern, affecting high-, low-, and middle-income countries [...].

Nanomaterials-plants-microbes interaction: plant growth promotion and stress mitigation

Soil salinization, extreme climate conditions, and phytopathogens are abiotic and biotic stressors that remarkably reduce agricultural productivity. Recently, nanomaterials have gained attention as effective agents for agricultural applications to mitigate such stresses. This review aims to critically appraise the available literature on interactions involving nanomaterials, plants, and microorganisms. This review explores the role of nanomaterials in enhancing plant growth and mitigating biotic and abiotic stresses. These materials can be synthesized by microbes, plants, and algae, and they can be applied as fertilizers and stress amelioration agents. Nanomaterials facilitate nutrient uptake, improve water retention, and enhance the efficiency of active ingredient delivery. Nanomaterials strengthen plant antioxidant systems, regulate photosynthesis, and stabilize hormonal pathways. Concurrently, their antimicrobial and protective properties provide resilience against biotic stressors, including pathogens and pests, by promoting plant immune responses and optimizing microbial-plant symbiosis. The synergistic interactions of nanomaterials with beneficial microorganisms optimize plant growth under stress conditions. These materials also serve as carriers of nutrients, growth regulators, and pesticides, thus acting like "smart fertilizers. While nanotechnology offers great promise, addressing potential environmental and ecotoxicological risks associated with their use is necessary. This review outlines pathways for leveraging nanotechnology to achieve resilient, sustainable, and climate-smart agricultural systems by integrating molecular insights and practical applications.

The impact of phenotypic heterogeneity on fungal pathogenicity and drug resistance

Phenotypic heterogeneity in genetically clonal populations facilitates cellular adaptation to adverse environmental conditions while enabling a return to the basal physiological state. It also plays a crucial role in pathogenicity and the acquisition of drug resistance in unicellular organisms and cancer cells, yet the exact contributing factors remain elusive. In this review, we outline the current state of understanding concerning the contribution of phenotypic heterogeneity to fungal pathogenesis and antifungal drug resistance.

Exploring the Diversity and Ecological Dynamics of Palm Leaf Spotting Fungi-A Case Study on Ornamental Palms in Portugal

Palm trees (Arecaceae) are among the most popular ornamental plants worldwide. Despite extensive research on the fungi associated with Arecaceae, the diversity and ecological dynamics of fungi affecting ornamental palms remain poorly studied, although they have significant impact on palm health and economic value. Furthermore, while research on palm fungal diversity has traditionally focused on tropical assemblages, ornamental palms in temperate climates offer a unique opportunity to explore the diversity of palm fungi in non-native habitats. The present study conducted a preliminary assessment of the diversity and ecology of potential phytopathogenic fungi associated with foliar lesions on various ornamental palm host species in Portugal, combining morphological examination, PCR-based genomic fingerprinting, and biodiversity data analysis. The examination of 134 foliar lesions sampled from 100 palm trees resulted in a collection of 2064 palm leaf spotting fungi (PLSF), representing a diverse fungal assemblage of 320 molecular operational taxonomic units (MOTUs) across 97 genera. The overall fungal community composition revealed a distinct assemblage dominated by Neosetophoma, Alternaria, Phoma, and Cladosporium, with a profusion of infrequent and rare taxa consistent with a logseries distribution. Significantly positive co-occurrence (CO) patterns among prevalent and uncommon taxa suggest potential synergistic interactions enhancing fungal colonisation, persistence, and pathogenicity. The taxonomic structures of the PLSF contrasted markedly from tropical palm fungi, especially in the prevalence of pleosporalean coelomycetes of the Didymellaceae and Phaeosphaeriaceae, including recently introduced or not previously documented genera on Arecaceae. This novel assemblage suggests that climatic constraints shape the structure of palm fungal communities, resulting in distinctive temperate and tropical assemblages. In addition, the fungal assemblages varied significantly across palm host species, with temperate-native palms hosting more diverse, coelomycete-enriched communities. The present findings highlight foliar lesions as hyperdiverse microhabitats harbouring fungal communities with intricate interactions and a complex interplay of climatic, host, and ecological factors. With climate change altering environmental conditions, the identification of fungi thriving in or inhabiting these microhabitats becomes crucial for predicting shifts in pathogen dynamics and mitigating future fungal disease outbreaks. Understanding these complex ecological dynamics is essential for identifying potential phytopathogenic threats and developing effective management strategies for the health and sustainability of ornamental plants.

Insights into the origin, hybridisation and adaptation of Candida metapsilosis hybrid pathogens

Hybridisation is a source of genetic diversity, can drive adaptation to new niches and has been found to be a frequent event in lineages harbouring pathogenic fungi. However, little is known about the genomic implications of hybridisation nor its impact on pathogenicity-related traits. A common limitation for addressing these questions is the narrow representativity of sequenced genomes, mostly corresponding to strains isolated from infected patients. The opportunistic human pathogen Candida metapsilosis is a hybrid that descends from the crossing between unknown parental lineages. Here, we sequenced the genomes of five new C. metapsilosis isolates, one representing the first African isolate for this species, and four environmental isolates from marine niches. Our comparative genomic analyses, including a total of 29 sequenced strains, shed light on the phylogenetic relationships between C. metapsilosis hybrid isolates and show that environmental strains are closely related to clinical ones and belong to different clades, suggesting multiple independent colonisations. Furthermore, we identify a new diverging clade likely emerging from the same hybridisation event that originated two other previously described hybrid clades. Lastly, we evaluate phenotypes relevant during infection such as drug susceptibility, thermotolerance or virulence. We identify low drug susceptibility phenotypes which we suggest might be driven by loss of heterozygosity events in key genes. We discover that thermotolerance is mainly clade-dependent and find a correlation with the faecal origin of some strains which highlights the adaptive potential of the fungus as commensal.

Invasive fungal disease in the immunocompromised host: changing epidemiology, new antifungal therapies, and management challenges

BACKGROUND

Invasive fungal disease (IFD) causes morbidity and mortality in immunocompromised hosts (ICHs). Based on increasing recognition of the impact of IFD on human disease, a recent WHO priority list identified key areas of need.

OBJECTIVES

This review examines changes in the epidemiology of IFD, in particular the emergence of antifungal-resistant pathogens and the current availability of rapid diagnostic tests and antifungal treatment options.

SOURCES

Literature between 2000 and January 2024 regarding fungal epidemiology, diagnostic tests, antifungal resistance, emerging fungal pathogens, and novel antifungal agents in both adult and paediatric ICH were reviewed.

CONTENT

We describe the changing epidemiology and continued burden and mortality of IFD in ICH. Furthermore, we discuss the emergence of antifungal-resistant organisms driven by new immunosuppressed populations, climate change, and antifungal exposure in the individual and environment. We highlight novel antifungal agents and how they will address current unmet needs.

IMPLICATIONS

The changing epidemiology and increased population at risk for IFD, lack of recognition or quantification of risks for IFD with new therapies, current gaps in the availability of rapid diagnostic tests, and the imminent availability of novel antifungals with distinct spectra of activity argue for improved availability of and access to rapid diagnostics, antifungal stewardship programmes, and global access to antifungal agents.

Navigating Host Immunity and Concurrent Ozone Stress: Strain-Resolved Metagenomics Reveals Maintenance of Intraspecific Diversity and Genetic Variation in Xanthomonas on Pepper

The evolving threat of new pathogen variants in the face of global environmental changes poses a risk to a sustainable crop production. Predicting and responding to how climate change affects plant-pathosystems is challenging, as environment affects host-pathogen interactions from molecular to the community level, and with eco-evolutionary feedbacks at play. To address this knowledge gap, we studied short-term within-host eco-evolutionary changes in the pathogen, Xanthomonas perforans, on resistant and susceptible pepper in the open-top chambers (OTCs) under elevated Ozone (O3) conditions in a single growing season. We observed increased disease severity with greater variance on the resistant cultivar under elevated O3, yet no apparent change on the susceptible cultivar. Despite the dominance of a single pathogen genotype on the susceptible cultivar, the resistant cultivar supported a heterogeneous pathogen population. Altered O3 levels led to a strain turnover, with a relatively greater gene flux on the resistant cultivar. Both standing genetic variation and de novo parallel mutations contributed toward evolutionary modifications during adaptation onto the resistant cultivar. The presence of elevated O3, however, led to a relatively higher genetic polymorphism, with random and transient mutations. Population heterogeneity along with genetic variation, and the promotion of interdependency are mechanisms by which pathogen responds to stressors. While parallel mutations may provide clues to predicting long-term pathogen evolution and adaptive potential. And, a high proportion of transient mutations suggest less predictable pathogen evolution under climatic alterations. This knowledge is relevant as we study the risk of pathogen emergence and the mechanisms and constraints underlying long-term pathogen adaptation under climatic shifts.

Identification of Fungal Species Associated with Gall Oak (Quercus infectoria) Decline in Iran

The gall oak (Quercus infectoria Oliv.) tree is one of the most important and valuable forestry species in the Northern Zagros forests in the west of Iran. Gall oak decline is considered to be one of the most important diseases currently affecting the Zagros oak forests in Iran. The main objective of the present study, conducted in the years 2021 to 2023, was to investigate the possible role of fungi as causative agents of gall oak dieback in the Zagros forests of Iran. Wood samples were taken from gall oak trees showing canker, dieback, and internal wood discoloration symptoms. Fungal isolates recovered from gall oak trees were identified based on cultural and morphological characteristics, as well as phylogenetic analyses using DNA sequencing of the internal transcribed spacer region of rDNA and partial beta-tubulin. Achaetomium aegilopis, Alternaria tenuissima, Apiospora intestini, Botrytis cinerea, Coniochaeta sp., Coniothyrium palmarum, Coniothyrium sp., Cytospora rhodophila, Dialonectria episphaeria, Diatrype sp., Diatrypella macrospora, Endoconidioma populi, Fonsecazyma sp., Fusarium ipomoeae, Jattaea discreta, Kalmusia variispora, Microsphaeropsis olivacea, Neoscytalidium dimidiatum, Paecilomyces lecythidis, Paramicrosphaeropsis eriobotryae, Paramicrosphaeropsis ellipsoidea, and Seimatosporium pezizoides were identified from diseased trees. Pathogenicity tests were performed by artificial inoculation of excised branches of healthy gall oak trees under controlled conditions and evaluated after 35 days by measuring the discolored lesion length at the inoculation site. N. dimidiatum was the most virulent species and caused the longest wood necrosis within 35 days of inoculation. In the greenhouse test, only some species induced typical symptoms of canker. All isolated fungi are reported for the first time on gall oak trees in the world.

Elsinoe species: The rise of scab diseases

The genus Elsinoe contains many aggressive pathogens of a wide range of plants, many of which are economically important. These fungal pathogens cause serious scab diseases affecting various plant parts, impacting plant vigour, yield and market value. While studies on Elsinoe species have predominantly focused on their taxonomy, there is a conspicuous gap in knowledge of these fungi from a plant pathology perspective. In this review, we draw together and critically evaluate the existing, but rather fragmented, research on the taxonomic status, phylogenetic relationships, host range, as well as the biology and epidemiology of Elsinoe species. Our aim is primarily to augment the existing understanding of the global significance of Elsinoe species, and furthermore, to shed light on the escalating prominence of scab diseases caused by species in a fungal genus that has been known for over 100 years but remains relatively poorly understood and somewhat enigmatic.

Engineering Adhesion of the Probiotic Strain Escherichia coli Nissle to the Fungal Pathogen Candida albicans

Engineering live biotherapeutic products against fungal pathogens such as Candida albicans has been suggested as a means to tackle the increasing threat of fungal infections and the development of resistance to classical antifungal treatments. One important challenge in the design of live therapeutics is to control their localization inside the human body. The specific binding capability to target organisms or tissues would greatly increase their effectiveness by increasing the local concentration of effector molecules at the site of infection. In this study, we utilized surface display of carbohydrate binding domains to enable the probiotic E. coli Nissle 1917 to adhere specifically to the pathogenic yeast Candida albicans. Binding was quantified using a newly developed method based on the automated analysis of microscopic images. In addition to a rationally selected chitin binding domain, a synthetic peptide of identical length but distinct sequence also conferred binding. Efficient binding was specific to fungal hyphae, the invasive form of C. albicans, while the yeast form, as well as abiotic cellulose and PET particles, was only weakly recognized.

Global patterns of species diversity and distribution in the biomedically and biotechnologically important fungal genus Aspergillus

Aspergillus fungi are key producers of pharmaceuticals, enzymes, and food products and exhibit diverse lifestyles, ranging from saprophytes to opportunistic pathogens. To improve understanding of Aspergillus species diversity, identify key environmental factors influencing their geographic distributions, and estimate the impact of future climate change, we trained a random forest machine learning classifier on 30,542 terrestrial occurrence records for 176 species (~40% of known species in the genus) and 96 environmental variables. We found that regions with high species diversity are concentrated in temperate forests, which suggests that areas with mild seasonal variation may serve as diversity hotspots. Species range estimates revealed extensive variability, both within and across taxonomic sections; while some species are cosmopolitan, others have more restricted ranges. Furthermore, range overlap between species is generally low. The top predictors of mean species richness were the index of cumulative human impact and five bioclimatic factors, such as temperature and temperate vs non-temperate ecoregions. Our future climate analyses revealed considerable variation in species range estimates in response to changing climates; some species ranges are predicted to expand (e.g., the food spoilage and mycotoxin-producing Aspergillus versicolor), and others are predicted to contract or remain stable. Notably, the predicted range of the major pathogen Aspergillus fumigatus was predicted to decrease in response to climate change, whereas the range of the major pathogen Aspergillus flavus was predicted to increase and gradually decrease. Our findings reveal how both natural and human factors influence Aspergillus species ranges and highlight their ecological diversity, including the diversity of their responses to changing climates, which is of relevance to pathogen and mycotoxin risk assessment.

Protists and protistology in the Anthropocene: challenges for a climate and ecological crisis

Eukaryotic microorganisms, or "protists," while often inconspicuous, play fundamental roles in the Earth ecosystem, ranging from primary production and nutrient cycling to interactions with human health and society. In the backdrop of accelerating climate dysregulation, alongside anthropogenic disruption of natural ecosystems, understanding changes to protist functional and ecological diversity is of critical importance. In this review, we outline why protists matter to our understanding of the global ecosystem and challenges of predicting protist species resilience and fragility to climate change. Finally, we reflect on how protistology may adapt and evolve in a present and future characterized by rapid ecological change.

CRISPR-GRIT: Guide RNAs with Integrated Repair Templates Enable Precise Multiplexed Genome Editing in the Diploid Fungal Pathogen Candida albicans

Candida albicans, an opportunistic fungal pathogen, causes severe infections in immunocompromised individuals. Limited classes and overuse of current antifungals have led to the rapid emergence of antifungal resistance. Thus, there is an urgent need to understand fungal pathogen genetics to develop new antifungal strategies. Genetic manipulation of C. albicans is encumbered by its diploid chromosomes requiring editing both alleles to elucidate gene function. Although the recent development of CRISPR-Cas systems has facilitated genome editing in C. albicans, large-scale and multiplexed functional genomic studies are still hindered by the necessity of cotransforming repair templates for homozygous knockouts. Here, we present CRISPR-GRIT (Guide RNAs with Integrated Repair Templates), a repair template-integrated guide RNA design for expedited gene knockouts and multiplexed gene editing in C. albicans. We envision that this method can be used for high-throughput library screens and identification of synthetic lethal pairs in both C. albicans and other diploid organisms with strong homologous recombination machinery.

Dryland fungi are spatially heterogeneous and resistant to global change drivers

Fungi are considered particularly important in regulating the structure and function of dryland ecosystems, yet the response of dryland fungal communities to global change remains notably understudied. Without a clear understanding of how fungi respond to global change drivers, mitigation plans-required for biodiversity and ecosystem service conservation and restoration-are impossible to develop. In this study we asked the following: (1) how does the fungal community respond to the individual and interactive effects of physical disturbance and drought in a heterogeneous dryland landscape comprised of drought-adapted shrubs separated by adjacent open areas of soil, and (2) what are the larger scale impacts of this response? We assessed fungal communities (using fungal-specific DNA metabarcoding analyses) of surface soil samples in an in situ global change experiment that included disturbance and drought in a full factorial design in the northern extent of the Chihuahuan Desert. We found that the fungal community was spatially heterogenous and remarkably resistant to disturbance and drought. We also show that dryland soils harbor high shares of facultative pathogenic and obligately pathogenic fungal taxa, with several concerning taxa reaching high relative abundances under drought. Our results suggest that the fungal community is highly influenced by microclimatic conditions associated with the presence or absence of vegetation. Moreover, our results imply that the fungal community in our experiment was already adapted to the magnitude of stress imposed by two years of experimental disturbance and drought treatments. Overall, our study shows that the fungal community is spatially heterogeneous, resistant to global change drivers, and houses many fungal species known for being stress tolerant and pathogenic.

To be or not to be a nonhost species: A case study of the Leptosphaeria maculans and Brassica carinata interaction

Leptosphaeria maculans is one of the major fungal pathogens on oilseed rape (Brassica napus), causing stem canker disease. The closely related Brassica species B. nigra, B. juncea, and B. carinata display extreme resistance toward stem canker. In this study, we demonstrate the nonhost status of B. carinata toward L. maculans in France through field experiments and inoculations performed in controlled conditions. A few isolates moderately adapted to B. carinata in controlled conditions were recovered in the field on B. nigra leaves, allowing us to investigate the unusual B. carinata-L. maculans interactions using molecular, macroscopic, and microscopic analyses. A cross between a L. maculans isolate adapted to B. napus and an isolate moderately adapted to B. carinata allowed the generation, in the lab, of recombinant L. maculans strains better adapted to B. carinata than the natural parental isolate obtained from B. nigra, and highlighted the polygenic determinism of the adaptation of L. maculans to B. carinata and B. napus. This biological material will allow further investigation of the molecular determinants of the adaptation of L. maculans to nonhost species and elucidate the genetic resistance basis of B. carinata.

Effects of global change drivers on the expression of pathogenicity and stress genes in dryland soil fungi

The impacts of global climate change on dryland fungi have been understudied even though fungi are extremely sensitive to changes in the environment. Considering that many fungi are pathogens of plants and animals, including humans, their responses to anthropogenic change could have important implications for public health and food security. In this study, we investigated the potential physiological responses (i.e., metatranscriptomics) of pathogenicity and stress in dryland fungi exposed to global change drivers, drought, and the physical disturbance associated with land use. Specifically, we wanted to assess if there was an increase in the transcription of genes associated to pathogenicity and stress in response to global change drivers. In addition, we wanted to investigate which pathogenicity and stress genes were consistently differentially expressed under the different global change conditions across the heterogeneous landscape (i.e., microsite) of the Chihuahuan desert. We observed increased transcription of pathogenicity and stress genes, with specific genes being most upregulated in response to global change drivers. Additionally, climatic conditions linked to different microsites, such as those found under patches of vegetation, may play a significant role. We provide evidence supporting the idea that environmental stress caused by global change could contribute to an increase of pathogenicity as global climate changes. Specifically, increases in the transcription of stress and virulence genes, coupled with variations in gene expression, could lead to the onset of pathogenicity. Our work underscores the importance of studying dryland fungi exposed to global climate change and increases in existing fungal pathogens, as well as the emergence of new fungal pathogens, and consequences to public health and food security.

IMPORTANCE

The effects of global climate change on dryland fungi and consequences to our society have been understudied despite evidence showing that pathogenic fungi increase in abundance under global climate change. Moreover, there is a growing concern that global climate change will contribute to the emergence of new fungal pathogens. Yet, we do not understand what mechanisms might be driving this increase in virulence and the onset of pathogenicity. In this study, we investigate how fungi respond to global change drivers, physical disturbance, and drought, in a dryland ecosystem in terms of pathogenicity and stress. We find that indeed, under global change drivers, there is an increase in the transcription and expression of genes associated to pathogenicity and stress, but that microclimatic conditions matter. Our study shows the importance of investigating dryland fungi exposed to global climate change and impacts on our society, which may include threats to public health and food security.

tRNA-m1A methylation controls the infection of Magnaporthe oryzae by supporting ergosterol biosynthesis

Ergosterols are essential components of fungal plasma membranes. Inhibitors targeting ergosterol biosynthesis (ERG) genes are critical for controlling fungal pathogens, including Magnaporthe oryzae, the fungus that causes rice blast. However, the translational mechanisms governing ERG gene expression remain largely unexplored. Here, we show that the Trm6/Trm61 complex catalyzes dynamic N1-methyladenosine at position 58 (m1A58) in 51 transfer RNAs (tRNAs) of M. oryzae, significantly influencing translation at both the initiation and elongation stages. Notably, tRNA m1A58 promotes elongation speed at most cognate codons mainly by enhancing eEF1-tRNA binding rather than affecting tRNA abundance or charging. The absence of m1A58 leads to substantial decreases in the translation of ERG genes, ergosterol production, and, consequently, fungal virulence. Simultaneously targeting the Trm6/Trm61 complex and the ergosterol biosynthesis pathway markedly improves rice blast control. Our findings demonstrate an important role of m1A58-mediated translational regulation in ergosterol production and fungal infection, offering a potential strategy for fungicide development.

The contribution of tropical long-term studies to mycology

Fungi are arguably the most diverse eukaryotic kingdom of organisms in terms of number of estimated species, trophic and life history strategies, and their functions in ecosystems. However, our knowledge of fungi is limited due to a distributional bias; the vast majority of available data on fungi have been compiled from non-tropical regions. Far less is known about fungi from tropical regions, with the bulk of these data being temporally limited surveys for fungal species diversity. Long-term studies (LTS), or repeated sampling from the same region over extended periods, are necessary to fully capture the extent of species diversity in a region, but LTS of fungi from tropical regions are almost non-existent. In this paper, we discuss the contributions of LTS of fungi in tropical regions to alpha diversity, ecological and functional diversity, biogeography, hypothesis testing, and conservation-with an emphasis on an ongoing tropical LTS in the Pakaraima Mountains of Guyana. We show how these contributions refine our understanding of Fungi. We also show that public data repositories such as NCBI, IUCN, and iNaturalist contain less information on tropical fungi compared to non-tropical fungi, and that these discrepancies are more pronounced in fungi than in plants and animals.

Perspectives on blastomycosis in Canada in the face of climate change

Blastomycosis is a disease of potentially varied presentations caused by thermally dimorphic fungi that appear as mold at ambient temperatures and transform to yeast at body temperature. Inhalation of aerosolized fungal spores represents the primary mode of transmission. Exposure may follow outdoor activities that disturb soil, which is warm, moist, acidic and rich in organic debris, particularly within forested areas and in proximity to waterways. Blastomycosis is endemic to several parts of Canada, but is only reportable in Ontario and Manitoba, with Northwestern Ontario being considered a hyperendemic area with average annual incidence rates of over 25 cases per 100,000 population. Delays in diagnosis and treatment are frequently observed as the symptoms and imaging findings of blastomycosis may initially be mistaken for community-acquired pneumonia, tuberculosis or malignancy, which can result in interim disease progression and worsening clinical outcomes. Risks from fungal infections such as blastomycosis are likely to increase with climate change-associated shifts in temperature and rainfall, and this may contribute to the geographic expansion of cases, a phenomenon that appears to be already underway. Further research investigating the ecological niche of Blastomyces and its climate sensitivity could help facilitate better modelling of the potential impacts of climate change on risks to Canadians and inform more effective methods of exposure prevention. Early clinical recognition and treatment of blastomycosis remain the key to minimizing morbidity and mortality.

Genome-wide differentiation corresponds to climatic niches in two species of lichen-forming fungi

Lichens can withstand fluctuating environmental conditions such as hydration-desiccation cycles. Many species distribute across climate zones, suggesting population-level adaptations to conditions such as freezing and drought. Here, we aim to understand how climate affects population genomic patterns in lichenized fungi. We analysed population structure along elevational gradients in closely related Umbilicaria phaea (North American; two gradients) and Umbilicaria pustulata (European; three gradients). All gradients showed clear genomic breaks splitting populations into low-elevation (Mediterranean zone) and high-elevation (cold temperate zone). A total of 3301 SNPs in U. phaea and 138 SNPs in U. pustulata were driven to fixation between the two ends of the gradients. The difference between the species is likely due to differences in recombination rate: the sexually reproducing U. phaea has a higher recombination rate than the primarily asexually reproducing U. pustulata. Cline analysis revealed allele frequency transitions along all gradients at approximately 0°C, coinciding with the transition between the Mediterranean and cold temperate zones, suggesting freezing is a strong driver of population differentiation. Genomic scans further confirmed temperature-related selection targets. Both species showed similar differentiation patterns overall, but different selected alleles indicate convergent adaptation to freezing. Our results enrich our knowledge of fungal genomic functions related to temperature and climate, fungal population genomics, and species responses to environmental heterogeneity.

Understanding the clinical and environmental drivers of antifungal resistance in the One Health context

Antifungal drugs have had a tremendous impact on human health and the yields of crops. However, in recent years, due to usage both in a health setting and in agriculture, there has been a rapid emergence of antifungal drug resistance that has outpaced novel compound discovery. It is now globally recognized that new strategies to tackle fungal infection are urgently needed, with such approaches requiring the cooperation of both sectors and the development of robust antifungal stewardship rationales. In this review, we examine the current antifungal regimes in clinical and agricultural settings, focusing on two pathogens of importance, Candida auris and Aspergillus fumigatus, examining their drivers of antifungal resistance, the impact of dual-use azoles and the impact agricultural practices have on driving the emergence of resistance. Finally, we postulate that a One Health approach could offer a viable alternative to prolonging the efficacy of current antifungal agents.

Fungal effectors: past, present, and future

Fungal effector proteins function at the interfaces of diverse interactions between fungi and their plant and animal hosts, facilitating interactions that are pathogenic or mutualistic. Recent advancements in protein structure prediction have significantly accelerated the identification and functional predictions of these rapidly evolving effector proteins. This development enables scientists to generate testable hypotheses for functional validation using experimental approaches. Research frontiers in effector biology include understanding pathways through which effector proteins are secreted or translocated into host cells, their roles in manipulating host microbiomes, and their contribution to interacting with host immunity. Comparative effector repertoires among different fungal-host interactions can highlight unique adaptations, providing insights for the development of novel antifungal therapies and biocontrol strategies.

Increased offspring size and reduced gestation length in an ectothermic vertebrate under a worst-case climate change scenario

As global temperatures continue to rise, understanding the impacts of warming environments has become increasingly important. Temperature is especially relevant for ectothermic organisms which depend upon consistent and predictable annual temperature cycles for reproduction and development. However, additional research is required in this area to elucidate the potential impacts of climate change on future generations. To understand how projected increases in environmental temperatures may impact reproductive outcomes within natural populations of ectothermic vertebrates, we manipulated minimum ambient temperatures during gestation in Red-sided garter snakes (Thamnophis sirtalis parietalis). Wild snakes were collected in the Interlake region of Manitoba, Canada during their spring mating season and allowed to mate in controlled conditions. For the duration of gestation, mated females were placed into one of two ambient thermal conditions: temperatures emulating those found in the species' natural habitat or temperatures with a consistent 5 °C increase to match end-of-century climate change projections. We recorded observations for each litter and all neonates resulting from controlled mating trials. We observed no difference in litter sizes or birth rates between thermal conditions. However, we observed a significant reduction in gestation length and significant increase to neonate body mass and body condition associated with increased ambient temperatures. These results suggest that increased minimum temperatures during gestation may confer reproductive benefits for the northern populations of this species even under the most extreme current modeled warming predictions. We discuss the broader implications of this effect, including possible negative ecological outcomes.

Evolutionary origin and population diversity of a cryptic hybrid pathogen

Cryptic fungal pathogens pose disease management challenges due to their morphological resemblance to known pathogens. Here, we investigated the genomes and phenotypes of 53 globally distributed isolates of Aspergillus section Nidulantes fungi and found 30 clinical isolates-including four isolated from COVID-19 patients-were A. latus, a cryptic pathogen that originated via allodiploid hybridization. Notably, all A. latus isolates were misidentified. A. latus hybrids likely originated via a single hybridization event during the Miocene and harbor substantial genetic diversity. Transcriptome profiling of a clinical isolate revealed that both parental subgenomes are actively expressed and respond to environmental stimuli. Characterizing infection-relevant traits-such as drug resistance and growth under oxidative stress-revealed distinct phenotypic profiles among A. latus hybrids compared to parental and closely related species. Moreover, we identified four features that could aid A. latus taxonomic identification. Together, these findings deepen our understanding of the origin of cryptic pathogens.

A review of the epidemiology of invasive fungal infections in Asian patients with hematological malignancies (2011-2021)

The incidence of invasive fungal infection (IFI) is increasing, especially among patients diagnosed with hematological malignancies due to their immunocompromised nature. Other risk factors include advanced age, exposure to immunosuppressants, neutropenia, and catheter use. Some of the most common IFI organisms reported are Candida and Aspergillus species, and other fungal species, including Scedosporium, Trichosporon, Cryptococcus, and Fusarium have also increasingly been reported in the past years. However, the epidemiologic data on IFI among patients with hematological malignancies in Asian countries are lacking. Therefore, we investigated published epidemiologic data on such cases from the past 10 years (2011-2021) and discuss the challenges faced in the diagnosis and management of IFIs in Asia.

Exploring the Frontier of Wheat Rust Resistance: Latest Approaches, Mechanisms, and Novel Insights

Wheat rusts, including leaf, stripe, and stem rust, have been a threat to global food security due to their devastating impact on wheat yields. In recent years, significant strides have been made in understanding wheat rusts, focusing on disease spread mechanisms, the discovery of new host resistance genes, and the molecular basis of rust pathogenesis. This review summarizes the latest approaches and studies in wheat rust research that provide a comprehensive understanding of disease mechanisms and new insights into control strategies. Recent advances in genetic resistance using modern genomics techniques, as well as molecular mechanisms of rust pathogenesis and host resistance, are discussed. In addition, innovative management strategies, including the use of fungicides and biological control agents, are reviewed, highlighting their role in combating wheat rust. This review also emphasizes the impact of climate change on rust epidemiology and underscores the importance of developing resistant wheat varieties along with adaptive management practices. Finally, gaps in knowledge are identified and suggestions for future research are made. This review aims to inform researchers, agronomists, and policy makers, and to contribute to the development of more effective and sustainable wheat rust control strategies.