Invasive candidiasis (IC) causes substantial mortality in critically ill children, yet pediatric data from Southeast Asia remain limited. We retrospectively studied 117 children aged ≤ 18 years with proven IC at a Thai tertiary center (2009–2023). Thirty-day mortality was 25.6%, rising to 47.1% in neonates; death occurred a median of 5.5 days after diagnosis. Firth penalized logistic regression identified septic shock (aOR, 4.89; 95% CI, 1.77–14.88) and thrombocytopenia (aOR, 3.74; 95% CI, 1.17–15.35) as independent mortality predictors, with septic shock remaining significant across all analytical frameworks, including Fine–Gray competing-risks analysis. Apparent mortality associated with absence of antifungal therapy reflected reverse causation: in all six untreated children who died, Candida was reported only 2–7 days after death. Candida albicans (43.6%), C. tropicalis (30.8%), and C. parapsilosis (24.8%) predominated; C. glabrata was absent. Non-albicans Candida was already common at the outset and showed no statistically detectable increase over 15 years. Among 45 consecutive pediatric bloodstream isolates (2021–2026), amphotericin B and echinocandins largely retained activity, whereas reduced azole susceptibility was concentrated in C. tropicalis (47.8% fluconazole-susceptible; 26.1% posaconazole wild-type). The reduced azole susceptibility of local C. tropicalis isolates argues for periodic reassessment of institutional susceptibility data rather than reliance on historical or external epidemiology; in comparable settings, an echinocandin or amphotericin B is a more reliable empiric choice than an azole, pending species identification and susceptibility results.
During growth and metabolism, the budding yeast Saccharomyces cerevisiae is continuously exposed to diverse environmental stresses, and conserved mitogen-activated protein kinase (MAPK) cascades execute core functions in stress sensing and adaptive regulation. The high-osmolarity glycerol (HOG) pathway, a classical MAPK cascade in S. cerevisiae, was initially identified as the core regulator of hyperosmotic stress responses. Over recent decades, accumulating evidence has revealed that the HOG pathway is not merely an osmoregulatory module but a versatile signaling hub that integrates multiple stress inputs and orchestrates a broad spectrum of adaptive responses. This review systematically summarizes the core architecture of the HOG pathway, including its upstream sensing branches (Sln1 and Sho1) and the conserved three-tiered MAPK cascade, with an emphasis on how different stressors engage distinct branches and lead to differential Hog1 phosphorylation kinetics. This review further discusses the multifaceted roles of the HOG pathway in stress adaptation, covering transcriptional reprogramming, cell cycle arrest, metabolic reprogramming centered on glycerol synthesis, and emerging functions such as cell wall remodeling, flocculation, mitophagy, and cross-talk with other MAPK pathways. By integrating classical and contemporary findings, this review presents a comprehensive view of the HOG pathway in S. cerevisiae and provides a reference for future research on stress signaling and engineering of this model organism.
Poria cocos (syn. Wolfiporia cocos) is an obligate saprophytic fungus that can produce sclerotia only when cultivated on pine wood. Despite its wide cultivation, the nutritional adaptation of this fungus to pine substrate and the host defensive responses triggered during colonization remain poorly characterized. Elucidating how Poria cocos colonizes pine and triggers host defenses is critical to uncover its nutrient dependence. GO and KEGG analyses revealed that protein degradation, carbon metabolism, protein processing in the endoplasmic reticulum, and proteasome pathways were the major enriched pathways, indicating that a large amount of pine wood protein was degraded after Poria cocos colonization. Consistent with these omics signatures, the fungus acquired its primary nitrogen source via breakdown of pine structural and metabolic proteins, while pine carbohydrates acted as its main carbon source. Nutritional profiling confirmed the depletion of soluble protein and total sugars in pine wood, alongside elevated defensive polyphenols and flavonoids, reflecting an active stress response from viable pine parenchyma cells upon colonization. No significant shifts in mineral element concentrations were detected in colonized pine wood, indicating that Poria cocos selectively absorbs target minerals without altering the overall mineral pool of host wood tissue. Collectively, this work elucidates the core nutritional strategy of Poria cocos during pine colonization and identifies key molecular clues to advance optimized artificial cultivation, laying a solid theoretical foundation for revealing its obligate saprophytic lifestyle.
Background: Disseminated invasive aspergillosis (IA) is an uncommon but devastating manifestation of disease, particularly when the central nervous system (CNS) is involved. The clinical features and outcomes of CNS dissemination, compared with isolated invasive pulmonary aspergillosis (IPA) and other disseminated forms, remain poorly characterized. Methods: Using an institutional database of 1157 cancer patients diagnosed with IA between 1993 and 2024, we identified 43 patients with disseminated IA, defined as infection involving ≥2 non-contiguous organ systems, including 8 with CNS involvement. Patients with disseminated IA were matched 1:3 to patients with IPA based on year of diagnosis. We compared clinical features, antifungal treatment, and outcomes between: (1) CNS-disseminated IA and IPA, and (2) CNS-disseminated IA and other forms of disseminated IA. Results: Baseline characteristics, including hematologic malignancy subtype, hematopoietic stem cell transplantation status, neutropenia, and antifungal prophylaxis, were similar across groups. Aspergillus fumigatus was the predominant species in all cohorts. No patients with CNS-disseminated IA achieved clinical response at end of therapy, versus 35% with IPA (p = 0.05) and 30% with other disseminated IA (p = 0.17). Twelve-week IA-associated mortality was significantly higher in CNS-disseminated IA than in IPA (88% vs. 45%, p = 0.028) and was higher than in other disseminated IA (88% vs. 46%, p = 0.05). Combination antifungal therapy was more frequently used in CNS-disseminated IA than in IPA (63% vs. 31%) and other disseminated IA (63% vs. 43%), while rates of ICU admission and mechanical ventilation were similar across groups. Conclusions: CNS involvement in disseminated IA defines a distinct, high-risk phenotype, with profoundly reduced treatment response and survival despite comparable baseline characteristics. Given the small number of CNS cases and the predominance of cases diagnosed during earlier study periods, these findings should be interpreted with caution. Although combination antifungal therapy was used more frequently in CNS-disseminated IA, no significant outcome benefit was observed, underscoring the need for improved therapeutic approaches for CNS aspergillosis in immunocompromised hosts.
The species diversity of lichenized fungi remains largely underestimated, yet the number of species in the cetrarioid core group of Parmeliaceae has remained stable while generic delimitations have been highly debated. Here, we performed a partitioned phylogenetic analysis incorporating secondary structure characters of three ribosomal loci (ITS, mtSSU, and nuLSU) combined with comprehensive phenotypic traits. Based on the results, we hypothesized that a Large Temporal Band (29.0–35.0 Mya) may serve as a baseline threshold for most generic divergences, corresponding to late-Oligocene global cooling and the primary cladogenesis of cetrarioid core lineages as documented in previous molecular dating studies. Additionally, we suggest a Small Temporal Band (14.0–18.0 Mya) for a subset of recently radiated genera that originated during the Mid-Miocene Climatic Optimum transition (~16 Mya). Two currently accepted genera (Cetraria and Nephromopsis) are largely supported in their current circumscriptions. Two new genera, Cetramelanelia and Tuckermanoides, are proposed to accommodate a clade of two species from Cetrariella and Tuckermanopsis platyphylla, respectively. Allocetraria is confirmed to resurrect as a genus separate from Cetraria, with Usnocetraria and Vulpicida treated as its synonyms. Foveolaria is reduced to synonymy with Nephromopsis. Ten new combinations and one new synonym at the species level are made. A dual-band temporal hypothesis for generic delimitation appears taxonomically reasonable for most macrolichens.
Candida auris is an emerging fungal pathogen that is posing a serious global health threat due to its high transmissibility and multidrug resistance profile. Despite recent molecular advances in scrutinizing this enigmatic microbe, much of our understanding regarding its pathomechanisms remains unelucidated. Since microbial pathogenesis is modulated by a dynamic interplay between the host and the pathogen, dissecting such host–pathogen interactions involving C. auris can shed novel insights into its pathogenic cascade. As such, to characterize the virulence repertoire of C. auris, this study applied an integrated quantitative proteomics strategy to scrutinize the early phase of infection. In vitro and in vivo experimental setups based on macrophage co-culture and murine intraperitoneal infection were utilized. Integrated proteomic analysis revealed a coordinated remodelling of cellular processes by C. auris during the early host–pathogen interaction phase, including downregulation of translational machinery, modulation of molecules involved in metabolic rewiring, stress responses, and structural rearrangements. Several proteins associated with oxidative stress adaptation, alternative carbon metabolism, and cytoskeletal regulation were differentially abundant during host interactions. Collectively, these findings demonstrate that early adaptation of C. auris to host immune pressure involves rapid and context-dependent proteome remodelling that may contribute to fungal survival and persistence during infection.
Antimicrobial resistance and the formation of biofilms in Gram-positive pathogens such as Streptococcus pneumoniae and Staphylococcus aureus are making the treatment of infections increasingly difficult. This study systematically evaluates the effect of gliotoxin (GT), an antimicrobial metabolite produced by Aspergillus fumigatus, on bacterial growth and biofilm formation, as well as its activity in combination with antibiotics. Three strains of S. pneumoniae and two strains of S. aureus (one methicillin-susceptible and one methicillin-resistant) were analysed. Planktonic growth was examined, and biofilm prevention assays were conducted by assessing biomass via crystal violet staining and viable cell counts. In addition, the combined effect of GT with cefotaxime and vancomycin was evaluated. GT inhibited planktonic growth and significantly reduced the biomass and viability of biofilms in a concentration-dependent manner. Moreover, its combination with conventional antibiotics (cefotaxime or vancomycin) showed strong synergy, drastically decreasing bacterial survival. These findings highlight the potent antibacterial and anti-biofilm activity of GT and its ability to enhance antibiotic efficacy, providing insight into fungal–bacterial interactions and suggesting potential therapeutic applications.
Abnormal tau expression is associated with disruption of cellular homeostasis and activation of stress-response pathways. However, the effects of vitamin B6 on cellular stress responses associated with tau expression remain unclear. In this study, the influence of vitamin B6 on oxidative stress responses, endoplasmic reticulum (ER) stress and unfolded protein response (UPR) signaling, autophagy-related gene expression, and apoptosis-related responses was investigated using a human tau-expressing Schizosaccharomyces pombe model. Cells expressing human tau were treated with pyridoxal 5′-phosphate (PLP), the biologically active form of vitamin B6, and changes in oxidative stress responses, endoplasmic reticulum (ER) stress and unfolded protein response (UPR) signaling, autophagy-related gene expression, apoptosis-related responses, and protein carbonyl content were evaluated. Tau expression was associated with increased expression of oxidative stress-, ER stress-, and autophagy-related genes. Vitamin B6 altered several of these responses, including the expression of ER stress- and oxidative stress-related genes. Although intracellular ROS levels increased following vitamin B6 treatment, protein carbonyl levels remained largely unchanged. In contrast, apoptosis-related responses showed only limited changes. These findings show that vitamin B6 is associated with changes in selected stress- and proteostasis-related responses in tau-expressing cells. The observed effects were not uniform across all pathways, indicating a complex relationship between vitamin B6, tau expression, and cellular stress responses. This study provides further insight into cellular responses associated with tau expression and supports further investigation of vitamin B6-mediated effects in more complex experimental models.
Open-field burning of agricultural residues is a persistent environmental challenge that contributes to greenhouse gas emissions, air pollution, and the loss of valuable biomass resources. This study developed sustainable mushroom cultivation substrates by replacing 50% of conventional sawdust with locally available agricultural residues, including corn stalks, rice straw, sugarcane leaves, and leaf litter, to reduce production costs, enhance mushroom productivity, and promote circular bioeconomy practices. The physicochemical properties, mycelial growth, contamination, yield performance, nutritional composition, economic feasibility, and environmental benefits of the alternative substrates were evaluated using Lentinus sajor-caju and Pleurotus species. Among the tested formulations, corn stalk-based substrates exhibited the most favorable characteristics, with improved nitrogen availability and a more balanced C/N ratio, resulting in faster colonization, lower contamination, quicker fruiting body formation period, and superior biological efficiency. The corn stalk formulation achieved the highest productivity across species, including biological efficiencies of 61.99% for L. sajor-caju, 102.79% for P. cornucopiae, 99.40% for P. ostreatus, and 101.96% for P. pulmonarius. In addition, alternative substrates maintained or enhanced mushroom nutritional quality, with high protein (18.22–31.37%), dietary fiber (up to 30.58%), and low-fat contents (1.11–1.95%). Economic analysis demonstrated that a 50:50 sawdust-biomass substitution strategy substantially reduced substrate costs, achieving approximately 30% savings at industrial production scales. Overall, this study demonstrates that converting agricultural residues into high-value mushroom substrates provides an effective strategy to improve production efficiency, reduce costs, and advance sustainable mushroom cultivation systems.
Background: Early diagnosis of Invasive Pulmonary Aspergillosis (IPA) in non-neutropenic ICU patients remains challenging due to the low specificity of radiological findings and the limited reliability of individual biomarkers. This diagnostic uncertainty often delays antifungal treatment and contributes to the high mortality associated with IPA. We aimed to develop a clinically interpretable model for early bedside risk stratification. Methods: We conducted a retrospective study including 298 ICU patients. A Logistic LASSO regression approach was used to identify the most informative predictors of IPA and to develop a parsimonious predictive model. Model performance was assessed through internal exploration and robustness testing under noise perturbation. Results: Three routinely available clinical variables were retained in the final model: pulmonary galactomannan, non-specific pulmonary infiltrates, and patient age, reflecting fungal burden, lung involvement, and host vulnerability, respectively, and identifying patients with a higher probability of culture-positive Aspergillus detection within a clinical context compatible with IPA. The final model showed promising discriminative performance, with an AUC of 0.836 ± 0.075, sensitivity of 0.72, and specificity of 0.74. Despite relying on only three routinely available clinical variables, the model maintained stable performance during internal exploration and robustness analyses. Conclusions: Within this cohort, the combination of positive pulmonary galactomannan, radiological infiltrates, and advanced age identifies a subgroup of ICU patients with a higher probability of microbiological positivity and clinical suspicion of IPA, supporting early risk assessment rather than definitive diagnosis. This simple and transparent predictive model may support early clinical evaluation and risk stratification of ICU patients and assist clinicians in identifying patients requiring further diagnostic assessment.
Globally, invasive fungal diseases are increasing in incidence and are associated with high rates of mortality. A lack of effective diagnostic protocols, antifungal resistance and poor antifungal stewardship contribute to negative outcomes. Aspergillus, Candida, Cryptococcus, and Pneumocystis are the most common pathogens associated with fatal fungal diseases. These species are responsible for 90% of reported invasive fungal deaths globally. Fungal species employ a diverse and effective array of virulence factors to sabotage, evade, and manipulate host immune systems, allowing for colonisation and dissemination in vivo. Invasive fungal infections are clinically challenging, as they penetrate organs and deep tissues, contributing to the aetiology of respiratory tract, endocarditis, meningitis, and medical device infections and resulting in false negative diagnostic attempts. The 2025 WHO report outlines a lack of diagnostic and therapeutic options available, especially in low-to-middle-income countries. Geographical and economic factors impact fungal disease and mortality rates. There is an urgent need for new approaches to combat fungal diseases clinically with improved biocompatibility profiles. This timely review discusses the prevalent invasive fungal species, namely, Candida, Aspergillus, Cryptococcus, and Pneumocystis, which have high mortality rates, as identified by the WHO priority pathogen list, and discusses recent advances in the treatment of fungal diseases. This dissemination of information is an important aspect of the United Nations Sustainable Development Goals (SDGs) and One Health.
Chinese chive (Allium tuberosum) suffers severe yield and quality losses from white leaf spot disease caused by Alternaria alternata. Spray-induced gene silencing (SIGS) presents a sustainable alternative to traditional chemical fungicides. To maximize the biocontrol efficacy of this approach, we designed dsRNAs targeting two candidate virulence-associated genes of Alternaria alternata: AaGH10, encoding a cell wall-degrading enzyme critical for host penetration, and AaSOD, an antioxidant enzyme crucial for reactive oxygen species (ROS) scavenging. We comprehensively evaluated the antifungal efficacy by assessing mycelial growth inhibition, spore germination, and lesion development through in vitro and in vivo assays. The results demonstrated that both single and combinatorial treatments effectively inhibited fungal growth and spore germination, thereby reducing disease incidence on detached leaves and intact greenhouse plants. The application of the dual-target dsRNA formulation achieved an 86.7% control efficacy on detached leaves. Furthermore, it significantly alleviated in vivo disease severity, decreasing the average number of necrotic lesions from 15.6 to 1.3 per leaf. These results demonstrate that the dual-target combination exerts an enhanced protective effect compared with individual interventions. This specific dual-target dsRNA formulation establishes a robust foundation for the control of Chinese chive white leaf spot disease.
Morchella is an edible and medicinal fungus valued for its distinctive flavor and nutritional properties. However, unstable yield and quality remain major constraints on its commercial cultivation. Although soybean meal is used as an organic nutrient supplement in edible mushroom production, its effects on protein accumulation and transcriptional regulation in Morchella remain unclear. This study combined fruiting-body protein measurements with transcriptome analysis to compare soybean meal supplied through soil application or exogenous nutrient bags and to characterize tissue-specific responses in the cap and stipe. Soybean meal increased protein content in an application method-, concentration-, and tissue-dependent manner. Soil application was more effective than nutrient-bag supplementation, while stipes exhibited a stronger transcriptional response than caps. RNA sequencing detected 11,982 expressed genes and revealed both shared and tissue-specific responses to the two supplementation methods. Gene Ontology analysis showed broadly similar functional categories among comparison groups, whereas KEGG enrichment analysis revealed distinct metabolic responses. In caps, soil application was associated with glutathione metabolism and amino sugar and nucleotide sugar metabolism, while nutrient-bag supplementation was associated with the pentose phosphate pathway, glyoxylate and dicarboxylate metabolism, and pentose and glucuronate interconversions. In stipes, the genes involved in ribosome and aminoacyl-tRNA biosynthesis were downregulated under soil application and nutrient-bag supplementation, respectively. Weighted gene co-expression network analysis identified three modules associated with protein content and highlighted ribosome, aminoacyl-tRNA biosynthesis, glycerophospholipid metabolism, and arginine biosynthesis as candidate pathways. The most highly connected genes in each key module were identified as hub genes, and selected expression patterns were supported by qRT-PCR. These findings provide a transcriptomic framework for understanding how soybean meal supplementation is associated with protein accumulation and tissue-specific physiological responses in Morchella.
We carried out carbohydrate composition and carbohydrate linkage analyses on Neurospora crassa cell walls from vegetative hyphae, conidia (asexual spores), perithecia (female mating structures), and ascospores (sexual spores). We show that the composition and structure of the cell wall undergo dramatic changes during the N. crassa life cycle. All the cell walls contain β-1,3-glucan and mixed β-1,3-/β-1,4-glucan (lichenin). The conidia cell walls and perithecia cell walls also contain α-1,3-glucan. β-1,3-glucan was the most abundant polysaccharide in the vegetative hyphae cell walls and mixed β-1,3-/β-1,4-glucan was the most abundant polysaccharide in the perithecia and ascospore cell walls. Chitin was a major polysaccharide in the ascospore cell walls. Ascospore and perithecia cell walls also contained melanin as a structural element. We conclude that the composition and structure of the cell wall changes dramatically as cells proceed through the various stages of the N. crassa life cycle.
A-to-I RNA editing is increasingly recognized as a regulator of fungal development and pathogenesis, yet its extent and lifecycle dependence remain poorly characterized in basidiomycetes. Microbotryum superbum (MvSup), M. intermedium (MI), and M. lychnidis-dioicae (MVLG) are members of the M. violaceum fungal complex. Each species infects specific host plant species, resulting in commonly anther-smut disease. The lifecycle of these basidiomycete fungi includes the haploid, mating, and infection stages. RNA editing is a post-transcriptional process where adenosine (A) is converted to inosine (I) by adenosine deaminase enzymes, and such modifications to RNAs may lead to synonymous and nonsynonymous codon changes, thereby altering protein function. Here, we compared A-to-I editing across the haploid, mating, and infection stages of these three related species to determine how editing patterns vary with lifecycle stage and among closely related fungal pathogens. The a2 haploid strain of MI had fewer editing sites compared to other haploid strains. The predicted codon/amino acid changes in each haploid strain across the three species indicated three primary types of resulting amino acid substitutions that were common to both of the mating-type strains across the three species: threonine to alanine, lysine to glutamic acid, and valine to alanine. During the mating stage of MvSup, a synonymous codon change was found in a mitogen-activated protein kinase domain-containing protein within the protein’s conserved region. Gene expression analysis revealed that certain genes, uniquely edited during the mating stage of MvSup, tend to be upregulated in the haploid stage but downregulated during mating, and vice versa. Research on RNA editing in basidiomycetes is relatively new. RNA editing mechanisms in fungi have been implicated in fungal pathogenesis, although the exact roles and implications remain unclear. Additional research will help us understand the functional significance of this apparently ubiquitous process in several members of the Microbotryum fungal complex, with possible ramifications more generally in fungi.
This study evaluated how culture system and culture medium composition influence the phenotype and functional quality of Talaromyces sayulitensis HC1 conidia. Conidia were produced by solid-state fermentation (SSF) and submerged fermentation (SmF) using two culture medium compositions differing in sucrose and ammonium phosphate concentrations and, consequently, in C:N ratio. Morphological, ultrastructural, physicochemical and functional attributes were analyzed together with the expression of four selected conidiation-related genes (brlA, abaA, fluG and rodA). Conidia produced under SSF were significantly smaller and displayed a more cylindrical morphology and accumulated significantly more melanin than those produced under SmF, whereas SmF-derived conidia exhibited significantly higher relative ergosterol content. Outer cell wall thickness was significantly influenced by both culture system and culture medium composition. Across both culture systems, the medium containing a lower sucrose concentration and a higher ammonium phosphate concentration (C:N ratio 10:1) resulted in significantly higher germination but significantly lower thermotolerance than the medium containing a higher sucrose concentration and a lower ammonium phosphate concentration (C:N ratio 50:1). The medium was also associated with significantly greater melanization. Expression of brlA, abaA, fluG and rodA was generally higher under SSF, although the magnitude of the response varied among genes and culture medium compositions. The integrated analysis revealed that germination and thermotolerance were not necessarily coupled and that culture system and culture medium composition influenced different dimensions of conidial quality. The main innovation of this study is the integration of structural, physicochemical, functional and selected molecular indicators to identify distinct conidial quality profiles relevant to application-oriented production of fungal inoculants.
The Pleosporales order is the largest in the Ascomycota phylum and is distributed worldwide, with a wide range of hosts and habitats. Members of this order are closely associated with the aquatic environment, including marine habitats. Many species are isolated from substrates such as mangroves, marine driftwood and seagrass. This study describes seven new species spanning three genera in two families: Montagnula minispora, Paraconiothyrium ellipsosporum, P. microconidium, P. qingdaoense, Westerdykella fulva, W.microcarpa, and W. sedimenticola. These new species can be differentiated morphologically from their close relatives by the presence of an anamorph, the type of sporangium and the color, shape and size of the conidia. The LSU-ITS-tef1-rpb2 phylogeny revealed seven independent and highly supported clades, providing important evidence for the introduction of these new species. Ecologically, they were retrieved from the marine environment, spanning the intertidal, coastal and deep-sea zones, thereby expanding our knowledge of the distribution and species diversity of pleosporalean fungi.
The heterothallic fungus Bipolaris maydis, the causal organism of southern corn leaf blight, is a destructive pathogen of corn and is considered to predominantly reproduce asexually, as no perfect reproductive stage has been discovered under natural conditions. In this study, a multiplex PCR with mating type-specific primers was used to investigate the temporal change and spatial distribution of mating types in several B. maydis populations in China. Mating type monitoring demonstrated that both mating types co-existed throughout the entire monitoring period across the seven monitoring locations, with mating type frequencies skewing significantly (p < 0.05) to MAT1-2 during the period of 2015 to 2020 and being practically symmetric after 2020, implying that the two populations were approaching equilibrium. Both mating type isolates were detected within the same leaf or field, affording a high theoretical likelihood for the two mating type isolates to cross sexually. In addition, both MAT1-1 and MAT1-2 isolates were detected from large-scale geographical regions in China, with mating type frequencies approaching a null hypothesis ratio of 1:1 in most populations, suggesting frequency-dependent selection consistent with sexual reproduction. Conclusively, our results provided indirect evidence supporting the potential for sexual reproduction in B. maydis under natural conditions, although no sexual morphs have yet been discovered in the field.
Donor-derived infections (DDIs), particularly fungal DDIs, are uncommon but serious complications of solid organ transplantation. We report a case of a 52-year-old woman who underwent deceased donor kidney transplantation complicated by probable donor-derived Candida albicans candidemia with native aortic valve endocarditis, managed medically with prolonged echinocandin therapy followed by suppressive fluconazole. Approximately 14 months post-transplant, she developed progressive rhino-orbital mucormycosis due to Rhizopus oryzae, requiring extensive surgical debridement and prolonged antifungal therapy. Initial treatment with liposomal amphotericin B was limited by nephrotoxicity, prompting transition to isavuconazole for long-term management. Immunosuppression was discontinued to control infection, resulting in graft failure. This case illustrates the complex interplay between donor-derived infection, antifungal exposure, and immunosuppression in transplant recipients. It highlights the potential contribution of antifungal selective pressure to breakthrough mold infections and underscores the importance of early recognition, aggressive multidisciplinary management, and individualized antifungal strategies in this high-risk population.
Lichen-forming fungi establish intimate symbiotic associations with photosynthetic partners and play important roles in diverse ecosystems, but functional genetic studies in these organisms remain limited by the lack of efficient genome-editing tools. In this study, we established an efficient CRISPR-Cas9-mediated gene disruption system in Umbilicaria muhlenbergii. Using this system, we achieved the targeted disruption of six candidate transcription factors with a high replacement efficiency of up to 65.0%. No off-target mutations were detected in any of the three independent mutants examined for each target gene. Preliminary phenotypic characterization of the resulting mutants revealed that disruption of UmSOM1 markedly impaired fungal growth, induced pseudohyphal development, and altered colony morphology and pigmentation. Compared with conventional homologous recombination, the CRISPR-Cas9 system substantially improved gene disruption efficiency, thereby overcoming a major limitation in the genetic manipulation of lichen-forming fungi. This system provides a robust platform for functional genomic studies and will accelerate investigations into the molecular mechanisms underlying fungal–algal symbiosis and morphological transitions in lichen-forming fungi.
