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The epidermal growth factor receptor (EGFR) has been identified as an epithelial cell receptor for Mucorales fungi and Candida albicans. Blocking EGFR with small molecule inhibitors reduces disease severity in mouse models of mucormycosis and oropharyngeal candidiasis. In contrast, cases of invasive aspergillosis have been reported in cancer patients who were treated with EGFR inhibitors, suggesting that EGFR signaling may play a protective role in the host defense against this infection. Here, we analyzed transcriptomic data from the lungs of mice with invasive aspergillosis and found evidence that Aspergillus fumigatus infection activates multiple genes that are predicted to function in the EGFR signaling pathway. We also found that A. fumigatus infection activates EGFR in both a human small-airway epithelial (HSAE) cell line and in the lungs of immunosuppressed mice. EGFR signaling in HSAE cells is required for maximal endocytosis of A. fumigatus and for fungal-induced proinflammatory cytokine and chemokine production. In a corticosteroid immunosuppressed mouse model of invasive pulmonary aspergillosis, inhibition of EGFR with gefitinib decreased whole-lung cytokine and chemokine levels and reduced accumulation of phagocytes in the lung, leading to a decrease in fungal killing, an increase in pulmonary fungal burden, and accelerated mortality. Thus, EGFR signaling is required for pulmonary epithelial cells to orchestrate the host innate immune defense against invasive aspergillosis in immunosuppressed hosts.IMPORTANCEWhen A. fumigatus infects the lungs, it invades epithelial cells that line the airways. During this process, the fungus interacts with epithelial cell receptors. This interaction stimulates epithelial cells to endocytose the fungus. It also induces these cells to secrete proinflammatory cytokines and chemokines that recruit phagocytes to the site of infection where they can kill the fungus. Here, we show that in small-airway epithelial cells, the EGFR acts as a sensor for A. fumigatus that triggers the production of chemokines in response to fungal infection. In corticosteroid-immunosuppressed mice, blocking EGFR with the kinase inhibitor gefitinib reduces chemokine production in the lungs. This leads to decreased accumulation of neutrophils and dendritic cells in the lungs, reduced A. fumigatus killing, and increased mortality. These results provide a potential explanation as to why some cancer patients who are treated with EGFR inhibitors develop invasive aspergillosis.

A new benzophenone derivative, 8′-hydroxymonomethylsulochrin (1), together with eighteen known compounds (2-19) were produced by the endophytic fungus Aspergillus fumigatus WJ-131, isolated from the stem of Gardenia jasminoides. The structure of 1 was determined by extensive spectroscopic analysis and X-ray crystallography. Under the condition of concentration of 20.0 μM, the splenic lymphocytes proliferation rates of compounds 1 and 7 induced by LPS were 39.4% and 38.1% (LPS, the splenic lymphocytes cell proliferation rates of 21.3%), and the splenic lymphocytes proliferation rate of compounds 7 induced by ConA is 44.6% (ConA, the splenic lymphocytes proliferation rates of 28.9%). Therefore, compounds 1 and 7 promoted the proliferation of ConA/LPS-stimulated splenic lymphocytes at 20.0 μM in vitro. In addition, compound 1 showed weak antibacterial activity against Fusarium oxysporum. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the most common malignancies. The currently available clinical drugs for HCC frequently cause serious side effects and the treatment outcomes are unsatisfactory. It is urgent to develop effective drugs with high selectivity and low adverse effects for HCC. Metabolites produced by microorganisms have shown great potential in the development of therapeutic agents for HCC. In our study, the EtOAc extract of the strain Aspergillus fumigatus YB4-17 exhibited significant cytotoxicity towards the HCC HepG2 cells at 10 μg/mL. Various column chromatographic separations of the extract afforded seven polyketides (1 – 7), including a new diphenyl ether derivative (1), along with fourteen known alkaloids (8 – 21). The structure elucidation was conducted via NMR spectroscopic data and MS data analysis. The absolute configuration of compound 11 was confirmed by comparing experimental and calculated electronic circular dichroism spectrum for the first time. The biological evaluation of these metabolites revealed that compound 11 selectively inhibited the proliferation of HCC HepG2 cells with negligible toxicity to normal cells. Mechanism study indicated that compound 11 induced apoptosis and paraptosis in HepG2 cells, providing a novel therapeutic perspective for the treatment of hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

Purpose: The primary objective was to evaluate the clinical response of refractory cases of fungal keratitis to topical 1% posaconazole therapy. Methods: Prospective longitudinal non-randomized open label dual-cohort study of 70 eyes of refractory fungal keratitis, 35 were recruited as posaconazole treatment (PCZ) group for topical 1% posaconazole therapy and compared to 35 eyes on conventional antifungal therapy. Study parameters included demographic and treatment details, visual acuity, comprehensive slit-lamp biomicroscopy, clinical photography, ASOCT at recruitment and weekly (week 1, 2, 3 and 4 after treatment initiation). Clinical assessment included keratitis severity grade, time of healing, and healing response. Anti-fungal susceptibility testing was performed. Results: The mean age of 35 patients recruited in the PCZ treatment group was 45 ± 17.32 years and that for the conventional treatment group was 43.22 ± 15.04 years. Culture isolation was possible in 25 eyes (71.4%) in the PCZ treatment group, with Fusarium and Aspergillus spp. being the most common cornea pathogenic mycotic organisms. The mean healing time in the PCZ group was 27.13 ± 5.8 days and in the conventional treatment group was 26.41 ± 4.81 days. Healing response in the PCZ treatment showed that 27 eyes (77.14%) had healed, 3 (8.5%) had delayed healing, and 5 (14.28%) required therapeutic keratoplasty, whereas in the conventional treatment group, 26 (74.28%) healed, 2 (5.7%) had delayed healing, and 7 (20%) needed keratoplasty (P = 0.65, 0.72, 0.54, respectively). Topical 1% PCZ therapy of chronic mycotic keratitis was helpful in resolution in 85.7% of cases (30 eyes) with five eyes needing surgical intervention, which was comparable to that of conventional antimycotic therapy cohorts. Fusarium isolates showed greater susceptibility to natamycin in our study per MIC50 values, with susceptibility to the common antimycotic agents varying between the Aspergillus spp. in both PCZ treatment and conventional treatment groups. All isolates showed minimal values of MIC-50 with PCZ. Antifungal susceptibility testing in our study recruits showed that about 90% of the Fusarium spp. isolates to be best responsive to natamycin and PCZ, whereas Aspergillus niger isolates were sensitive to voriconazole, itraconazole, amphotericin B, and PCZ, Aspergillus flavus to voriconazole and PCZ, Aspergillus fumigatus to both polyenes and triazoles. Cladosporium spp. were best sensitive to natamycin and PCZ, Penicillium spp. to natamycin and azoles. Alternaria keratitis isolates were sensitive to voriconazole and PCZ, whereas Rhizopus isolate was best sensitive to PCZ. Conclusion: Topical 1% PCZ therapy in refractory fungal keratitis was comparable to that of conventional antimycotic agents, with lower MIC-50 against the common pathogenic fungi as compared to natamycin, amphotericin B, and voriconazole. [ABSTRACT FROM AUTHOR]

There is growing evidence that bioactive substances produced by microbial endophytes have applicability in medicine, agriculture and industry. To enrich the bioactive substances, in our search for new bioactive metabolites from fungi Aspergillus, the phytochemical reinvestigation on the Aspergillus sp. 0338 was carried out, and this led to the isolation of three new (1-3) and five known alkaloids (4-8). Their structures were elucidated by spectroscopic analysis, including extensive 1D and 2D NMR techniques, as well as comparison with literature values. Additionally, compounds 1-3 were evaluated for their anti-MRSA activities. The results revealed that compounds 1-3 exhibited good inhibitions with IZD of 15.2 ± 1.8, 14.6 ± 2.0, and 13.4 ± 2.2 mm, respectively. [ABSTRACT FROM AUTHOR]

Zea mays L. (Maize) is one of the most crucial world's crops, for their nutritional values, however, the water scarcity and consequent soil salinization are the major challenges that limit the growth and productivity of this plant, particularly in the semi-arid regions in Egypt. Recently, biopriming has been recognized as one of the most efficient natural-ecofriendly approaches to mitigate the abiotic salt stress on plants. The haploid (128) and triploid (368) seeds of maize were selected as model verities for assessing their resistance to salt stress and mitigating their effect by fungal-biopriming. Overall, the haploid and triploid plants viabilities were drastically affected by salt concentration, at 500 mM of NaCl. At 500 mM NaCl, the fresh weights of the triploid and haploid seedlings were reduced by ~ 5 and 6.1 folds, compared to the controls, ensuring slightly higher salt resistance of the triploid than haploid ones. The pattern of the endophytic fugal isolates was plausibly changed with the salt concentration for both plant types, Aspergillus fumigatus isolate was emerged with the higher NaCl concentration (400–500 mM), and their morphological identity was molecularly confirmed and deposited into Genbank with accession # PQ200673. The fungal bioprimed seeds of the haploid and triploid plants were irrigated with 400 mM NaCl. The fungal-bioprimed plants displayed a significant improvement on the shoot density, fibrous roots, root length, shoot length, and leaves numbers and areas of the stressed-plants by ~ 1.7 folds, compared to control, ensures the triggering of different salt resistance machineries in plants upon fungal biopriming. The total antioxidant enzymes activities "catalase, peroxidase, superoxide dismutase" of the salt-stressed bioprimed maize plants were increased by ~ 4.7–5.3%, compared to control, confirming the mitigating effect of the salinity stress on plants upon fungal biopriming. The chlorophyll and carotenoids contents were significantly increased of the salt stressed maize upon biopriming with A. fumigatus. The expression of the sod, apx2, nhx11, hkt1, H + -PPase, nced of the plant salt stressed was strongly increased in response to A. fumigatus biopriming, normalized to β-actin gene. The expression of apx2 was dramatically increased by about 30 and 43 folds, in response to fungal biopriming. The nhx1 was significantly up-regulated by 18.9 fold in response to fungal biopriming, compared to control. [ABSTRACT FROM AUTHOR]

This paper introduces a novel, compact plasma sterilization system, the Active Plasma Sterilizer (APS), for planetary protection space missions. The development of the APS system is done through iterative testing and design modifications aimed at addressing decontamination modalities for time and temperature, cleaning adhesive surfaces, and cleaning protocols beyond alcohol and bleach. Decontamination testing of Deinococcus radiodurans, Geobacillus stearothermophilus (spore forming bacteria), and Aspergillus fumigatus (fungi) was verified for the APS on relevant materials of 4 to 5 log reduction up to complete killing in 45 min or less. The material compatibility testing of the APS performed with Stainless Steel 316, Teflon PTFE, and FR-4 PCB using a single exposure showed no visible material degradation through SEM analysis. This study demonstrates the efficacy of the APS technology for use with planetary protection due to its low-temperature operation, low weight and size, zero-plumbing requirements, safety features, decontamination capabilities, and material compatibility. [ABSTRACT FROM AUTHOR]

Fungi have an essential role in deterioration of historical leather bindings, leading to major problems in the preservative state of these artifacts. This study aims to evaluate the efficiency of some fungicides and nanoparticles materials against fungal activity of historical leather bindings. Historical leather binding from an illuminated paper manuscript dating back to the Mamluk period (1250–1516 AD) at the Al-Azhar library, Cairo, Egypt was examined for fungal infection, and isolation. Results of the present study showed, 21 fungal isolates were isolated and identified using morphological and molecular techniques as Alternaria alternate (5%), Aspergillus fumigatus (43%), Aspergillus niger (43%), Aspergillus terrus (5%), and Penicillium chrysogenum (5%). All fungal isolates exhibited proteolytic activity. Aspergillus niger (2–7) and Aspergillus fumigatus (3–4) achieved the highest proteolytic activity amongst obtained fungal strains. Seven fungicides, difenoconazole, propiconazole, azoxystrobin, pyraclostrobin, boscalid, dimethomorph, and thiophanate-methyl as individual active ingredient and two mixtures [difenoconazole combined with propiconazole (1:1)] and [boscalid combined with pyraclostrobin (2:1)] were evaluated at different concentrations against A. fumigatus and A. niger. Additionally, the effect of titanium and silicon dioxides nanoparticles, against the highest proteolytic fungi A. fumigatus and A. niger was evaluated. The fungal growth inhibition was assessed by the disc diffusion method (DDM). The results revealed that individual or mixed boscalid and pyraclostrobin fungicides at 300 ppm achieved the highest inhibition activity against A. fumigatus, but the linear diagram showed that individual boscalid and pyraclostrobin fungicides at 200 ppm was the ideal concentration for application with the leather samples in the future study. The mixture of boscalid + pyraclostrobin (2:1) exhibited the best preservation effect against A. niger achieving 65.9%, and 82.4% microbial inhibition at 150, and 300 ppm, respectively, followed by individual boscalid fungicide. [ABSTRACT FROM AUTHOR]

Background: Fungal spondylitis often occurs in patients with immune dysfunction, and its diagnosis and treatment pose certain challenges. However, even in immunocompromised patients, Aspergillus spondylitis remains rare. This case reports the diagnostic and therapeutic experience of fungal spondylitis in a patient with consolidated cirrhosis and no significant immune impairment. Case presentation: A 45-year-old agricultural worker had chest and back pain for 6 months. The patient's pain was a persistent dull ache that worsened with chronic coughing and postural changes and decreased when he was laying down. Based on the patient's clinical presentation, biochemical tests and imaging, considered possible spinal tuberculosis. Empirical anti-tuberculosis treatment was not successful. Due to the failure of medication and the formation of an epidural abscess, the decision was made to proceed with surgical treatment. Intraoperative tissue specimens were subjected to high throughput testing for culture, tuberculosis gene X-pert and high-throughput detection of macro-gene infectious agents. It was confirmed that the spinal infection was caused by Aspergillus fumigatus. Tuberculosis medication was ceased and antifungal therapy with voriconazole was started. Three months after surgery, the patient recovered well with no fever or pain. Discussion and conclusion: In summary, in addition to patients with low immune function who should be evaluated for fungal spondylitis, patients with infectious diseases of the spine who are immunocompetent but have comorbid cirrhosis should be evaluated when treatment fails. If the diagnosis cannot be made by conventional or unconventional methods, surgical methods should be used in a timely manner for diagnosis and treatment. [ABSTRACT FROM AUTHOR]

The environmental use of azole fungicides has led to selective sweeps across multiple loci in the Aspergillus fumigatus genome causing the rapid global expansion of a genetically distinct cluster of resistant genotypes. Isolates within this cluster are also more likely to be resistant to agricultural antifungals with unrelated modes of action. Here we show that this cluster is not only multi-azole resistant but has increased propensity to develop resistance to next generation antifungals because of variants in the DNA mismatch repair system. A variant in msh6-G233A is found almost exclusively within azole resistant isolates harbouring the canonical cyp51A azole resistance allelic variant TR34/L98H. Naturally occurring isolates with this msh6 variant display up to 5-times higher rate of mutation, leading to an increased likelihood of evolving resistance to other antifungals. Furthermore, unlike hypermutator strains, the G233A variant conveys no measurable fitness cost and has become globally distributed. Our findings further suggest that resistance to next-generation antifungals is more likely to emerge within organisms that are already multi-azole resistant due to close linkage between TR34/L98H and msh6-G233A, posing a major problem due to the prospect of dual use of novel antifungals in clinical and agricultural settings. Here, Bottery et al show that resistance to next generation antifungals is more likely to occur within azole resistant Aspergillus fumigatus due to the close linkage between a globally distributed azole resistance allele and a DNA repair variant which elevates mutation rates. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the most common malignancies. The currently available clinical drugs for HCC frequently cause serious side effects and the treatment outcomes are unsatisfactory. It is urgent to develop effective drugs with high selectivity and low adverse effects for HCC. Metabolites produced by microorganisms have shown great potential in the development of therapeutic agents for HCC. In our study, the EtOAc extract of the strain Aspergillus fumigatus YB4-17 exhibited significant cytotoxicity towards the HCC HepG2 cells at 10 μg/mL. Various column chromatographic separations of the extract afforded seven polyketides (1 – 7), including a new diphenyl ether derivative (1), along with fourteen known alkaloids (8 – 21). The structure elucidation was conducted via NMR spectroscopic data and MS data analysis. The absolute configuration of compound 11 was confirmed by comparing experimental and calculated electronic circular dichroism spectrum for the first time. The biological evaluation of these metabolites revealed that compound 11 selectively inhibited the proliferation of HCC HepG2 cells with negligible toxicity to normal cells. Mechanism study indicated that compound 11 induced apoptosis and paraptosis in HepG2 cells, providing a novel therapeutic perspective for the treatment of hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

Introduction: Temporary and extended drought stress accelerates phytohormones and reactive oxygen species (ROS) in plants, however, the fate of the plants under stress is mostly determined by the metabolic and molecular reprogramming, which can be modulated by the application of habitat-adapted fungi that triggers resistance to stress upon symbiotic association. Methods: The present research exhibited the exploitation of the newly isolated, drought habitat-adapted fungal endophytic consortium of SAB (Aspergillus oryzae) and CBW (Aspergillus fumigatus), on maize under drought stress. SAB and CBW primarily hosted the root tissues of Conyza bonariensis L., which have not been reported earlier, and sufficiently produced growth-promoting metabolites and antioxidants. Results: SAB and CBW adeptly inhabited the maize roots. They promoted biomass, primary metabolites, osmolytes (protein, sugar, lipids, proline, phenolics, flavonoids), and IAA production while reducing tannins, ABA, and H2O2 contents and increasing antioxidant enzyme activities. In addition, the enhanced adventitious root development at the root/stem interface, and elongated main root development optimum stomatal activity of SAB- and CBW-inoculated maize plants were observed under drought stress. SAB and CBW modulated the expression of the ZmBSK1 , ZmAPX , and ZmCAT1 genes in the maize shoot and root tissues under drought stress vs. control, signifying an essential regulatory function for SAB/CBW-induced drought stress tolerance via phytohormonal signaling pathway leading to the antioxidant upregulation. Discussion: These findings imply that the exogenous administration of the SAB/CBW consortium might be a rather efficient strategy that contributes to optimizing the physio-hormonal attributes and antioxidant potential to alleviate the drought stress in maize. Graphical abstract depicting the potential role of habitat-adapted fungal endophytes SAB and CBW cultivated maize resilience to drought by enhancing the growth, and stress tolerance, via brassinosteroid regulation, metabolic induction, elevation of osmolytes, antioxidant activation, and stomatal activity optimization. [ABSTRACT FROM AUTHOR]

Bronchiectasis-Chronic Obstructive Pulmonary Disease Overlap Syndrome (BCOS) is a complex pulmonary condition that merges bronchiectasis and chronic obstructive pulmonary disease (COPD), presenting unique clinical challenges. Patients with BCOS typically exhibit a range of symptoms from both conditions, including a chronic productive cough, reduced lung function, frequent exacerbations, and diminished exercise tolerance. The etiology of BCOS involves multiple factors such as genetic predisposition, respiratory infections, tobacco smoke, air pollutants, and other inflammatory mediators. Accurate diagnosis requires a comprehensive approach, incorporating pulmonary function tests to evaluate airflow limitation, radiographic imaging to identify structural lung abnormalities, and blood eosinophil counts to detect underlying inflammation. Treatment strategies are tailored to individual symptom profiles and severity, potentially including bronchodilators, inhaled corticosteroids, and pulmonary therapy to improve lung function and quality of life. Patients with BCOS are also at an increased risk for cardiovascular complications, such as stroke, ischemic heart disease, and cor pulmonale. Additionally, medications like beta-agonists and muscarinic antagonists used in COPD treatment can further affect cardiac risk by altering heart rate. This paper aims to provide a thorough understanding of BCOS, addressing its development, diagnosis, treatment, and associated cardiovascular complications, to aid healthcare providers in managing this multifaceted condition and improving patient outcomes. [ABSTRACT FROM AUTHOR]

Filamentous Fungal Human Pathogens (FFHPs) such as Aspergillus fumigatus, are growing resistant to currently available antifungal drugs. One possible target, the Nucleoside diphosphate kinase (Ndk) is significant for nucleotide biosynthesis and crucial for fungal metabolism. Violacein, a natural food colorant, was examined for its antifungal effects against Aspergillus fumigatus via computational approach against the Ndk protein. Known and predicted interactions of Ndk with proteins was performed using the STRING application. Molecular docking was performed using Schrodinger Maestro software (V.14.1) under enhanced precision docking, with OPLS4 forcefield. MDS was performed for 500ns under OPLS4 forcefield and the TIP3P solvent system. The geometry optimization for DFT was performed using the Becke 3-parameter exchange functional (B3LYP) method. The Molecular Docking Studies revealed significant interactions with good binding energy between Violacein and Ndk. Subsequent MD Simulations confirmed the stability of Violacein-Ndk complex, compared to the reference ligand-complex, indicating a stable interaction between the protein and violacein. The energy band gap of violacein was found to be 0.072567 eV suggesting its softness with lower kinetic stability and higher chemical reactivity. The results suggest Violacein could potentially disrupt nucleotide metabolism by targeting Ndk, thus demonstrating antifungal activity. However, further experimental validation is required to confirm these computational findings and explore the practical use of Violacein in antifungal treatments. [ABSTRACT FROM AUTHOR]

The human lung is confronted daily with thousands of microbial invaders reaching the lower respiratory tract. An efficient response by the resident type 1 and type 2 alveolar epithelial cells (AECs) and alveolar macrophages (AMs) cells during the early hours of innate immunity is a prerequisite to maintain a non-inflammatory state, but foremost to rapidly remove harmful substances. One such human-pathogenic invader is the opportunistic fungus Aspergillus fumigatus. If the spherical conidia are not cleared in time, they swell reaching approximately twice of their initial size and germinate to develop hyphae around six hours post-infection. This process of morphological change is crucial as it enables the pathogen to invade the alveolar epithelium and to reach the bloodstream, but also makes it conspicuous for the immune system. During this process, conidia are first in contact with AECs then with migrating AMs, both attempting to internalize and clear the fungus. However, the relative contribution of AMs and AECs to uptake of A. fumigatus remains an open question, especially the capabilities of the barely investigated type 1 AECs. In this study, we present a bottom-up modeling approach to incorporate experimental data on the dynamic increase of the conidial diameter and A. fumigatus uptake by AECs and AMs in a hybrid agent-based model (hABM) for the to-scale simulation of virtual infection scenarios in the human alveolus. By screening a wide range of parameters, we found that type 1 AECs, which cover approximately 95% of the alveolar surface, are likely to have a greater impact on uptake than type 2 AECs. Moreover, the majority of infection scenarios across the regime of tested parameters were cleared through uptake by AMs, whereas the contribution to conidial uptake by AECs was observed to be limited, indicating that their crucial support might mostly consist in mediating chemokine secretion for AM recruitment. Regardless, as the first host cell being confronted with A. fumigatus conidia, our results evidence the large potential impact of type 1 AECs antimicrobial activities, underlining the requirement of increasing experimental efforts on this alveolar constituent. Stochastic computer model of A. fumigtatus lung infections based on a bottom-up ODE approach, that incorporates wet lab data linking conidial swelling to its recognition and uptake, investigates the contribution of the lung epithelium and the alveolar macrophages to fungal clearance. [ABSTRACT FROM AUTHOR]

Aspergillus fumigatus is a widely distributed pathogen responsible for severe infections, particularly in immunocompromised individuals. Triazoles are the primary treatments options for Aspergillus infections; however, the emergence of acquired resistance to this antifungal class is becoming a growing concern. In this study, we investigated the potential of the antiviral drug, lopinavir (LPV) to restore the susceptibility of A. fumigatus strains to a set of azoles, while also reducing the required azole dosage for treatment of susceptible isolates. The combination of LPV with either itraconazole (ITC) or posaconazole (POS) demonstrated potent synergistic interactions against 16 out of 23 (~70%) and 21 out of 23 (~91%) A. fumigatus isolates, respectively. Moreover, the combination showed synergistic activity against other clinically important Aspergillus species, including A. niger, A. flavus, and A. brasiliensis. The fractional inhibitory concentration index (FICI) for the combinations ranged from 0.18 to 0.313 for ITC and 0.091 to 0.313 for POS, indicating strong synergistic effects. Further investigation revealed that efflux pump inhibition contributed to the synergy observed between azole and LPV. Morphological examination of the fungal cells subjected to this combinational therapy at sub-inhibitory doses showed the presence of carbohydrate granules/patches. The identification of LPV as a promising adjunct therapy holds promise for addressing the emerging challenge of azole resistance in Aspergillus species and improving treatment outcomes for patients. [ABSTRACT FROM AUTHOR]

A mechanistic basis is described for assessment of resistance risk to medical antifungal treatments from agricultural use of fungicides of the same mode of action. The following need to occur in landscape environments for a risk to be posed by dual use: (i) emergence, whereby a resistant strain emerges by mutation and invasion; (ii) selection, whereby a mutation conferring a fitness advantage is selected for in the presence of fungicide; and (iii) exposure of humans to resistant strains from the landscape, potentially resulting in invasive fungal infection. We identify 20 human pathogens for which there is evidence that all three processes above could, in principle, occur. A model is derived to explore what determines resistance emergence and selection in human pathogens in landscape environments. Knowledge gaps are identified in key parameters. The analysis suggests that emergence and selection were particularly affected by fitness cost associated with the resistance mutation(s) and fungicide concentration. Emergence was also determined by the amount of pathogen reproduction (related to pathogen population size). If fungicide resistance is associated with even a small fitness cost, then environments with low fungicide concentrations, such as field soils, may not be conducive to resistance emergence or selection. These general findings were related to a specific case of observational data from the Netherlands for Aspergillus fumigatus. The analysis supports previous work that compost is towards the high‐risk end of the spectrum for this species. Agricultural soils, nonagricultural land and grassland were lower risk. [ABSTRACT FROM AUTHOR]

This review explores current advancements and challenges in antifungal therapies amid rising fungal infections, particularly in immunocompromised patients. We detail the limitations of existing antifungal classes—azoles, echinocandins, polyenes, and flucytosine—in managing systemic infections and the urgent need for alternative solutions. With the increasing incidence of resistance pathogens, such as Candida auris and Aspergillus fumigatus, we assess emerging antifungal agents, including Ibrexafungerp, T-2307, and N′-Phenylhydrazides, which target diverse fungal cell mechanisms. Innovations, such as nanoparticles, drug repurposing, and natural products, are also evaluated for their potential to improve efficacy and reduce resistance. We emphasize the importance of novel approaches to address the growing threat posed by fungal infections, particularly for patients with limited treatment options. Finally, we briefly examine the potential use of artificial intelligence (AI) in the development of new antifungal treatments, diagnoses, and resistance prediction, which provides powerful tools in the fight against fungal pathogens. Overall, we highlight the pressing need for continued research to advance antifungal treatments and improve outcomes for high-risk populations. [ABSTRACT FROM AUTHOR]

Due to the high morbidity and mortality rates of invasive aspergillosis (IA) and the importance of early IA detection for successful treatment and subsequent outcome, this study aimed to determine a time course of detectable antigen in a mouse model of IA and correlate it with tissue invasion by using two novel monoclonal antibodies, 1D2 and 4E4, that can be used to detect the Aspergillus-derived glycoproteins. Immunocompromised mice were randomly divided into five groups: uninfected control, and inoculation with conidia from Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, and Aspergillus terreus. Conidia (2 × 106 cells/mL) were administered intravenously via tail vein injection. Three mice from each group were euthanised at each time point (6 h, 12 h, 18 h, 24 h, and 48 h) after inoculation. Urine and blood were collected for analysis using a double-sandwich ELISA using 1D2 and 4E4. Liver, spleen, and kidney tissues were harvested for tissue staining. The levels of liver injury in the IA mice progressively increased with time after inoculation with Aspergillus conidia. Following inoculation with A. fumigatus, swollen conidia were identified in the spleen, as well as antigens in blood after 18 h. Hyphae were detected in the spleen, liver, and kidney after 48 h. For A. flavus, the antibodies detected hyphae in the liver and spleen as well as circulating antigens in blood samples 48 h after inoculation. Tissue injury was observed in the mice inoculated with A. terreus and A. niger, but there was no evidence of fungal invasion or antigens in the blood. Antigens were not detectable in mouse urine but could be detected in glomeruli of the kidney by immunofluorescence. In conclusion, the mAb-based antigen detection double-sandwich ELISA results were consistent with the IHC results in this study. Novel monoclonal antibodies 1D2 and 4E4 can serve as tools for the early identification of IA in mice infected by A. fumigatus and A. flavus. This study also suggests the potential usefulness of this approach in human disease. [ABSTRACT FROM AUTHOR]

The importance of manganese superoxide dismutase (Mn-SOD), an evolutionarily ancient metalloenzyme that maintains the integrity and function of mitochondria, was studied in oxidative stress-treated Aspergillus fumigatus cultures. Deletion of the Mn-SOD gene (sodB) increased both the menadione sodium bisulfite (MSB)-elicited oxidative stress and the deferiprone (DFP)-induced iron limitation stress sensitivity of the strain. Moreover, DFP treatment enhanced the MSB sensitivity of both the gene deletion mutant and the reference strain. The lack of SodB also increased the susceptibility of conidia to killing by human macrophages. Concurring with the stress sensitivity data, RNS sequencing data also demonstrated that the deletion of sodB largely altered the MSB-induced oxidative stress response. The difference between the oxidative stress responses of the two strains manifested mainly in the intensity of the response. Importantly, upregulation of "Ribosome protein", "Iron uptake", and "Fe-S cluster assembly" genes, alterations in the transcription of "Fe-S cluster protein" genes, and downregulation of "Heme binding protein" genes under MSB stress were characteristic only for the ΔsodB gene deletion mutant. We assume that the elevated superoxide level generated by MSB treatment may have destroyed Fe-S cluster proteins of mitochondria in the absence of SodB. This intensified the resynthesis of Fe-S cluster proteins, which was accompanied with enhanced translation and iron acquisition, leading to increased DFP sensitivity. [ABSTRACT FROM AUTHOR]

Aspergillus fumigatus is intrinsically resistant to the widely used antifungal fluconazole, and therapeutic failure can result from acquired resistance to voriconazole, the primary treatment for invasive aspergillosis. The molecular basis of substrate specificity and innate and acquired resistance of A. fumigatus to azole drugs were addressed using crystal structures, molecular models, and expression in Saccharomyces cerevisiae of the sterol 14α-demethylase isoforms AfCYP51A and AfCYP51B targeted by azole drugs, together with their cognate reductase AfCPRA2 and AfERG6 (sterol 24-C-methyltransferase). As predicted by molecular modelling, functional expression of CYP51A and B required eburicol and not lanosterol. A crowded conformationally sensitive region involving the BC-loop, helix I, and the heme makes AfCYP51A T289 primarily responsible for resistance to fluconazole, VT-1161, and the agrochemical difenoconazole. The Y121F T289A combination was required for higher level acquired resistance to fluconazole, VT-1161, difenoconazole, and voriconazole, and confirms posaconazole, isavuconazole and possibly ravuconazole as preferred treatments for target-based azole-resistant aspergillosis due to such a combination of mutations. [ABSTRACT FROM AUTHOR]

Fungal infections significantly threaten public health, and many strains are resistant to antifungal drugs. Marine Actinobacteria have been identified as the generators of powerful bioactive compounds with antifungal activity and can be used to address this issue. In this context, strains of Actinomycetes were isolated from the marine area of Rachgoun Island, located in western Algeria. The isolates were phenotypically and genetically characterized. The most potent antifungal isolate was selected, and its crude extract was purified and characterized by the GC/MS method. The results revealed that the STR2 strain showed the strongest activity against at least one target fungal species tested on a panel of fungal pathogens, including Candida albicans, Aspergillus fumigatus, Aspergillus niger, and Fusarium oxysporum. The molecular assignment of the STR2 strain based on the 16S rRNA gene positioned this isolate as a Streptomyces bacillaris species. The presence of safranal (2,3-dihydro-2,2,6-trimethylbenzaldehyde) in the crude chloroform extract of Streptomyces bacillaris STR2 strain was discovered for the first time in bacteria using chromatographic analysis of its TLC fractions. Moreover, certain molecules of biotechnological interest, such as phenols, 1,3-dioxolane, and phthalate derivatives, were also identified. This study highlights the potential of marine actinomycetes to produce structurally unique natural compounds with antifungal activity. [ABSTRACT FROM AUTHOR]

Fungal pathogens cause over a billion human infections annually, leading to more than 1.6 million deaths each year. The scarcity of available antifungal drugs intensifies the public health threat posed by human pathogenic fungal infections. Therefore there is a critical demand for novel, safe, and effective antifungal agents. Although chitinases are established as effective antifungal agents against phytopathogenic fungi, research on their activity against human pathogenic fungi is limited. The present study seeks to investigate the anti-inflammatory and antifungal activity of bacterial and fungal chitinase against human pathogenic fungi. The antifungal efficacy of bacterial chitinase from Streptomyces griseus, fungal chitinase from Trichoderma viride, and a combination of both was determined by calculating the inhibition percentage in fungal growth, indicated by the reduction in the dry mass of the fungi. Additionally, the anti-inflammatory activity of these chitinases was assessed by measuring the inhibition of albumin denaturation. Results revealed that chitinases exhibited greater antifungal activity compared to the standard. Notably, bacterial chitinase demonstrated higher effectiveness than fungal chitinase against Aspergillus fumigatus, while the bacterial and fungal chitinase had similar effects against different Cryptococcus neoformans and Candida species. The combination of bacterial and fungal chitinase demonstrated the highest antifungal activity against all tested fungi. Furthermore, the anti-inflammatory activity indicated that chitinases prevented 98% of albumin denaturation, marking the first study reporting the anti-inflammatory role of chitinases in preventing albumin denaturation. Additional in-vivo studies are necessary to explore the antifungal activity of chitinases against human pathogenic fungi and investigate the anti-inflammatory mechanisms of chitinase. [ABSTRACT FROM AUTHOR]

The present study outlines an easy, cheap, and environmentally friendly way to make Staphylococcus aureus-mediated bimetallic silver-copper nanocomposites (Ag/Cu) that can fight cancer and germs. The gram-positive S. aureus synthesized Ag, Cu, and their bi-metallic nanocomposites extracellularly. We aimed to prepare the bimetallic nanocomposite in two different ways, and we compared them in terms of characterization and biological applications. The first one is a bimetallic nanocomposite (Ag/Cub) that was made by mixing Ag and Cu metal ions in equal amounts (50:50). Then, the whole mixture was reduced. The second is the after-reduction bimetallic nanocomposite (Ag/Cua), in which each metal ion was reduced separately, and then the nanocomposites were mixed (50:50%) during biological applications. Nanocomposites were characterized using UV–visible spectrophotometry, Fourier-transform infrared spectroscopy, dynamic light scattering, and transmission electron microscopy. The results demonstrated that surface plasmon bands were at 320 nm for Ag NPs and 525 nm for Cu NPs, and a shift from these peaks was observed at 290 nm in the Ag/Cub bimetallic nanocomposite. The synthesized nanocomposites were confirmed to be in the nanoscale with 20, 40, and 80 nm spherical crystals, respectively. Nanocomposites were assayed for their antimicrobial activity against the gram-negative Pseudomonas aeruginosa, the acid-fast Mycobacterium smegmatis, the gram-positive Bacillus cereus, and S. aureus, in addition to three fungal species, which were Aspergillus flavus, A. fumigatus, and Candida albicans. The minimum inhibitory concentration and minimum bactericidal concentration were determined. The Ag/Cua/Cuaetallic nanocomposite was the most potent antimicrobial compound. The anticancer activity of the tested compounds was assayed against the hepatocellular carcinoma cell line (HepG-2). Low cytotoxic activity was recorded in most assayed nanocomposites against the baby hamster kidney cell line (BHK). [ABSTRACT FROM AUTHOR]

Infections caused by the airborne fungal pathogen, Aspergillus fumigatus, are increasing in severity due to growing numbers of immunocompromised individuals and the increasing incidence of antifungal drug resistance, exacerbating treatment challenges. Gallium has proven to be a strong candidate in the fight against microbial pathogens due to its iron-mimicking capability and substitution of Ga(III) in place of Fe(III), disrupting iron-dependent pathways. Since the antimicrobial properties of 2,2′-bipyridine and derivatives have been previously reported, we assessed the in vitro activity and proteomic effects of a recently reported heteroleptic Ga(III) polypyridyl catecholate compound against A. fumigatus. This compound has demonstrated promising growth-inhibition and impact on the A. fumigatus proteome compared to untreated controls. Proteins associated with DNA replication and repair mechanisms along with lipid metabolism and the oxidative stress responses were elevated in abundance compared to control. Crucially, a large number of mitochondrial proteins were reduced in abundance. Respiration is an important source of energy to fuel metabolic processes required for growth, survival and virulence, the disruption of which may be a viable strategy for the treatment of microbial infections. [ABSTRACT FROM AUTHOR]

Patients infected with antifungal-resistant fungi often do not respond to therapy, substantially increasing mortality risk. Some fungi are inherently resistant to particular antifungals, underscoring the importance of rapid genus identification or, ideally, rapid species identification. The past decade has seen an increase in variable antifungal resistance rates among human fungal pathogens, necessitating individual isolate testing. Various antifungal susceptibility testing (AFST) methods are most suitable for resource-constrained settings, including agar diffusion, gradient diffusion, broth microdilution, and automated tests, which all differ in speed, reliability, and cost; yet AFST remains largely unavailable in resource-constrained settings. This Personal View explores the feasibility of AFST implementation in resource-constrained settings and addresses broader accessibility concerns. We outline seven steps for implementation of AFST with an initial focus on accurate species identification (to predict intrinsic resistance) of Candida albicans, Candida parapsilosis, Candida glabrata , and Aspergillus fumigatus. New funding, laboratory and clinical training, clear protocols, access to media and reagents, acquisition and maintenance of quality control strains, and regular participation in an external quality assurance programme are all essential for sustainable AFST services. AFST is fundamental for patient care guidance, surveillance data generation, and strengthening antifungal stewardship programmes. Political commitment and international collaborations are crucial for enhanced AFST service delivery. [ABSTRACT FROM AUTHOR]

Introduction: Allergic bronchopulmonary aspergillosis (ABPA) is a lung disease caused by a hypersensitivity reaction to antigens of Aspergillus fumigatus. Objective: The aim of this study was to evaluate the long-term clinical outcomes of omalizumab use in patients with ABPA. Methods: In this retrospective study, 12 patients diagnosed with ABPA and receiving omalizumab for at least 2 years, and 32 patients diagnosed with severe allergic asthma and receiving omalizumab for at least 2 years (control group) were evaluated. Results: Evaluation was made of a total of 44 participants, comprising 11 (25%) males and 33 (75%) females, who received omalizumab for at least 2 years with the diagnosis of the control group (n = 32) and ABPA (n = 12). The increase in asthma control test (ACT) score after omalizumab was significant at 12 months and at 24 months in patients with ABPA. After omalizumab, the use of oral corticosteroid (OCS), the annual number of asthma attacks and hospitalizations were significantly decreased at 12 months and at 24 months in patients with ABPA. The increase in forced expiratory volume in 1 s (FEV1) (%) and ACT score after omalizumab were significant at 12 months and at 24 months in the control group. After omalizumab, the use of OCS, annual number of asthma attacks and hospitalizations were significantly decreased at 12 months and at 24 months in the control group. Conclusion: Long-term omalizumab use in patients with ABPA seems to be an effective treatment for improving pulmonary function and reducing asthma exacerbations and hospitalizations. [ABSTRACT FROM AUTHOR]

Invasive fungal infections including invasive pulmonary aspergillosis (IPA) generally have a poor prognosis, because the fungi spread throughout various organs. Therefore, it is important to accurately identify the fungal species for treatment. In this article, we present the results of pathological and molecular morphological analyses that were performed to elucidate the cause of respiratory failure in a patient who died despite suspicion of IPA and treatment with micafungin (MCFG). Pathological analysis revealed the existence of cystic and linear fungi in lung tissue. The fungi were identified as Aspergillus fumigatus (A. fumigatus) by partial sequencing of genomic DNA. Correlative light microscopy and electron microscopy (CLEM) analysis confirmed that fungi observed with light microscopy can also be observed with scanning electron microscopy (SEM) using formalin-fixed paraffin-embedded tissue sections. SEM revealed an atypical ultrastructure of the fungi including inhomogeneous widths, rough surfaces, and numerous cyst-like structures of various sizes. The fungi showed several morphological changes of cultured A. fumigatus treated with MCFG that were previously reported. Our results indicate that integrated analysis of ultrastructural observation by SEM and DNA sequencing may be an effective tool for analyzing fungi that are difficult to identify by conventional pathological analysis. [ABSTRACT FROM AUTHOR]

Gliotoxin (GT), a secondary metabolite and virulence factor of the fungal pathogen Aspergillus fumigatus, suppresses innate immunity and supports the suppression of host immune responses. Recently, we revealed that GT blocks the formation of the chemotactic lipid mediator leukotriene (LT)B4 in activated human neutrophils and monocytes, and in rodents in vivo, by directly inhibiting LTA4 hydrolase. Here, we elucidated the impact of GT on LTB4 biosynthesis and the entire lipid mediator networks in human M1‐ and M2‐like monocyte‐derived macrophages (MDMs) and in human tissue‐resident alveolar macrophages. In activated M1‐MDMs with high capacities to generate LTs, the formation of LTB4 was effectively suppressed by GT, connected to attenuated macrophage phagocytic activity as well as human neutrophil movement and migration. In resting macrophages, especially in M1‐MDMs, GT elicited strong formation of prostaglandins, while bacterial exotoxins from Staphylococcus aureus evoked a broad spectrum of lipid mediator biosynthesis in both MDM phenotypes. We conclude that GT impairs functions of activated innate immune cells through selective suppression of LTB4 biosynthesis, while GT may also prime the immune system by provoking prostaglandin formation in macrophages. [ABSTRACT FROM AUTHOR]

Background/Objectives: Airborne exogenous antigen inhalation can induce neutrophil infiltration of the airways, while eosinophils migrate to the airways in allergic airway inflammation. During a bacterial infection, Th2-associated cytokine IL-4, by binding to the IL-4 receptor (IL-4R), can suppress neutrophil recruitment to the site of inflammation. In the present study, we estimated whether the IL-4-dependent suppression of neutrophil recruitment contributed to the development of an immune response in asthma. Methods: Using a mouse model of Aspergillus fumigatus extract-induced allergic airway inflammation, we investigated the proportions of eosinophils and neutrophils in blood, lungs, and bone marrow over time. Bronchoalveolar lavage (BAL) fluid cytokine (including IL-4) levels and the proportions of bone marrow IL-4Rα (CD124)-expressing neutrophils were estimated. Results: We identified skewing from the neutrophil- to eosinophil-mediated immune response in the blood after five extract applications. At this point, the BAL fluid IL-4 level was not elevated, while IL-12p40 and CXCL1 levels were considerably increased. At the early stage of allergic airway inflammation, the proportions of neutrophils expressing CD124 and circulating neutrophils expressing CXCR2 (CD182) were significantly increased. Upon inflammation progression, the former remained elevated, but the latter significantly decreased. Conclusions: Thus, in allergic airway inflammation, bone marrow neutrophils become insensible to the attractive chemokine CXCL1 signals and susceptible to IL-4 effects. [ABSTRACT FROM AUTHOR]

Multiple human and plant pathogens are dispersed and transmitted as bioaerosols (e.g., Mycobacterium tuberculosis, SARS-CoV-2, Legionella pneumophila, Aspergillus fumigatus, Phytophthora spp., and Fusarium graminearum). Rapid, on-site methods to detect airborne pathogens would greatly enhance our ability to monitor exposure and trigger early mitigation measures across different settings. Analysis of air samples for microorganisms in a regulatory context is often based on culture-based methods, which are slow, lack specificity, and are not suitable for detecting viruses. Molecular methods (based on nucleic acids) could overcome these challenges. For example, loop-mediated isothermal amplification (LAMP) is rapid, sensitive, specific, and may detect microbial pathogens from air samples in under 60 min. However, the low biomass in air samples makes recovering sufficient nucleic acids for detection challenging. To overcome this, we present a simple method for concentrating bioaerosols collected through liquid impingement (one of the most common methods for bioaerosol collection). This method paired with LAMP (or other molecular approaches) offers simple, rapid, and sensitive detection of pathogens. We validated this method using three airborne pathogens (Mycobacterium tuberculosis, Legionella pneumophila, and Aspergillus fumigatus), and we were able to detect fewer than five cells in a 15 mL liquid impinger air sample in under 60 min. This simple method offers rapid pathogen detection without the use of specialist equipment, and it can be used across healthcare, education, environmental monitoring, and military settings. [ABSTRACT FROM AUTHOR]

Background:Aspergillus tracheobronchitis (AT) is an uncommon yet severe form of invasive pulmonary aspergillosis, with a notably low incidence among individuals living with HIV infection—accounting for merely 4.5% (7 out of 156 cases) in recent reviews. The advent of modern antiretroviral therapy (ART) has significantly altered the landscape of opportunistic infections in HIV, rendering conditions like AT rare in well‐controlled cases. Case Presentation: We present the case of a woman in her mid‐20s with well‐managed HIV infection who experienced a 4‐week history of fever and dyspnea. Diagnostic procedures, including bronchoscopy, revealed granulation tissue obstructing her right main bronchus. Cultures confirmed infection with Aspergillus fumigatus, leading to a diagnosis of AT. Despite initial positive response to voriconazole treatment, the patient developed severe hemoptysis and unfortunately succumbed to the complication. Conclusion: This case underscores the critical need for healthcare providers to consider AT in the differential diagnosis of respiratory symptoms in HIV‐positive patients, even when HIV is well‐controlled with ART. Early recognition and prompt antifungal therapy are essential for improving outcomes. Clinicians should remain vigilant for severe complications like hemoptysis, which can occur despite appropriate therapy. This report highlights the ongoing necessity for vigilance and proactive intervention in the care of individuals living with HIV. [ABSTRACT FROM AUTHOR]

Objective: The fungal unfolded protein response consists of a two-component relay in which the ER-bound sensor, IreA, splices and activates the mRNA of the transcription factor, HacA. Previously, we demonstrated that hacA is essential for Aspergillus fumigatus virulence in a murine model of fungal keratitis (FK), suggesting the pathway could serve as a therapeutic target. Here we investigate the antifungal properties of known inhibitors of the mammalian Ire1 protein both in vitro and in a treatment model of FK. Methods: The antifungal activity of Ire1 inhibitors was tested against conidia of several A. fumigatus isolates by a broth microdilution assay and against fungal biofilm by XTT reduction. The influence of 4μ8C on hacA mRNA splicing in A. fumigatus was assessed through gel electrophoresis and qRT-PCR of UPR regulatory genes. The toxicity and antifungal profile of 4μ8C in the cornea was assessed by applying drops to uninfected or A. fumigatus -infected corneas 3 times daily starting 4 hours post-inoculation. Corneas were evaluated daily through slit-lamp imaging and optical coherence tomography, or at endpoint through histology or fungal burden quantification via colony forming units. Results: Among six Ire1 inhibitors screened, the endonuclease inhibitor 4μ8C displayed the strongest antifungal profile with an apparent fungicidal action. The compound both blocked conidial germination and hyphal metabolism of A. fumigatus Af293 in the same concentration range that blocked hacA splicing and UPR gene induction (60-120 µM). Topical treatment of sham-inoculated corneas with 0.5 and 2.5 mM 4μ8C did not impact corneal clarity, but did transiently inhibit epithelialization of corneal ulcers. Relative to vehicle-treated Af293-infected corneas, treatment with 0.5 and 2.5 mM drug resulted in a 50% and >90% reduction in fungal load, respectively, the latter of which corresponded to an absence of clinical signs of infection or corneal pathology. Conclusion: The in vitro data suggest that 4μ8C displays antifungal activity against A. fumigatus through the specific inhibition of IreA. Topical application of the compound to the murine cornea can furthermore block the establishment of infection, suggesting this class of drugs can be developed as novel antifungals that improve visual outcomes in FK patients. [ABSTRACT FROM AUTHOR]

Seed vigor encompasses the germination capacity, ability to form seedlings, and potential for production of seeds, and during storage, the deterioration of seed vigor is an inevitable biological process. However, changes in the microflora of the seed surface and seed vigor under different storage conditions have rarely been studied. In this study, the changes in fungal species on the surface and embryo and their effects of the hybrid maize cultivar Zhengdan958 seeds under different storage conditions were studied. The seed vigor was evaluated according to standard germination, MDA content, respiration rate, ATP content and the integrity of the ATP synthase subunits of seed embryos, with the aim of providing a basis for revealing the molecular mechanism of seed deterioration. The results revealed that at 33% relative humidity (RH), the dominant microflora constituent on the seed surface was Fusarium sp. In the seed embryo, the dominant microflora constituent was Aspergillus fumigatus. At 91% RH, the dominant microflora constituent on the seed surface was Aspergillus Jensen. In the seed embryo, the dominant microflora constituent was Penicillium sp. With the increased RH in the storage environment, the seed germination rate decreased by 86.67%. The respiration rate decreased by 0.04 mg·g-1·h-1 after 24 h imbibition. The seed embryo was hardly stained via TTC. The MDA content increased by 0.99 nmol·g-1, and the ATP content decreased by 0.33 μmol·g-1 after 24 h imbibition. The mRNA integrity of ATP synthase α, β, γ and δ subunits, except for ε subunit, in the seed embryo decreased to different degrees. These findings suggest that a change in the microflora is one of the most important factors causing a decrease in or total loss of seed vigor. [ABSTRACT FROM AUTHOR]

The zebrafish (Danio rerio) has emerged as a valuable model for studying host-pathogen interactions due to its unique combination of characteristics. These include extensive sequence and functional conservation with the human genome, optical transparency in larvae that allows for high-resolution visualization of host cell-microbe interactions, a fully sequenced and annotated genome, advanced forward and reverse genetic tools, and suitability for chemical screening studies. Despite anatomical differences with humans, the zebrafish model has proven instrumental in investigating immune responses and human infectious diseases. Notably, zebrafish larvae rely exclusively on innate immune responses during the early stages of development, as the adaptive immune system becomes fully functional only after 4–6 weeks post-fertilization. This window provides a unique opportunity to isolate and examine infection and inflammation mechanisms driven by the innate immune response without the confounding effects of adaptive immunity. In this review, we highlight the strengths and limitations of using zebrafish as a powerful vertebrate model to study innate immune responses in infectious diseases. We will particularly focus on host-pathogen interactions in human infections caused by various bacteria (Clostridioides difficile, Staphylococcus aureus, and Pseudomonas aeruginosa), viruses (herpes simplex virus 1, SARS-CoV-2), and fungi (Aspergillus fumigatus and Candida albicans). [ABSTRACT FROM AUTHOR]

GH10 xylanases and GH62 Arabinofuranosidases play key roles in the breakdown of arabinoxylans and are important tools in various industrial and biotechnological processes, such as renewable biofuel production, the paper industry, and the production of short-chain xylooligosaccharides (XOS) from plant biomass. However, the use of these enzymes in industrial settings is often limited due to their relatively low thermostability and reduced catalytic efficiency. To overcome these limitations, strategies based on enzymatic chimera construction and the use of metal ions and other cofactors have been proposed to produce new recombinant enzymes with improved catalytic activity and thermostability. Here, we examine the conformational dynamics of a GH10-GH62 chimera at different calcium ion concentrations through molecular dynamics simulations. While experimental data have demonstrated improved activity and thermostability in GH10-GH62 chimera, the mechanistic basis for these enhancements remains unclear. We explored the structural details of the binding subsites of Ca2+ in the parental enzymes GH62 from Aspergillus fumigatus (Afafu62) and a recombinant GH10 from Cryptococcus flavescens (Xyn10cf), as well as their chimeric combination, and how negatively charged electron pairing located at the protein surface affects Ca2+ capture. The results indicate that Ca2+ binding significantly contributes to structural stability and catalytic cavity modulation in the chimera, particularly evident at a concentration of 0.01 M. This effect, not observed in the parental GH10 and GH62 enzymes, highlights how Ca2+ enhances stability in the overall chimeric enzyme, while supporting a larger cavity volume in the chimera GH62 subunit. The increased catalytic site volume and reduced structural flexibility in response to Ca2+ suggest that calcium binding minimizes non-productive conformational states, which could potentially improve catalytic turnover. The findings presented here may aid in the development of more thermostable and efficient catalytic systems. [ABSTRACT FROM AUTHOR]

Indoleamine 2,3‐dioxygenase (IDO) is a monomeric heme enzyme that catalyzes the oxidative cleavage of tryptophan (L‐Trp) to form N‐formyl‐kynurenine. Similar to other heme proteins, IDO only binds to O2 when the heme iron is ferrous (FeII), thereby rendering the enzyme active. Thus, ascorbate (Asc, a reducing agent) and methylene blue (MB, an electron carrier) are commonly added to in vitro IDO assay systems. However, Asc and MB have been recently reported to significantly impact the measurement of the enzymatic parameters of vertebrate IDO. Aspergillus fumigatus is a filamentous fungus and the most common cause of invasive aspergillosis; it has three IDO genes (IDOα, IDOβ, and IDOγ). The FeII–O2 IDOs of A. fumigatus, particularly FeII–O2 IDOγ, have relatively long half‐lives in their autoxidation; however, the autoxidation was accelerated by Asc. Similar to vertebrate IDOs, Asc acted as a competitive (or mixed‐competitive) inhibitor of the IDOs of A. fumigatus. A positive correlation (in the order of IDOγ > IDOβ > IDOα) was observed between the inhibitory sensitivity of the IDOs to Asc and the facilitation of their autoxidation by Asc. The FeII–O2 IDO can repeat the dioxygenase reaction as long as it reacts with L‐Trp; however, substrate‐free FeII–O2 IDO is converted into inactive FeIII–IDO by autoxidation. Thus, L‐Trp (which keeps the IDO active) competes with Asc (which inactivates IDO by accelerating autoxidation). This is probably why Asc, which is structurally quite different from L‐Trp, appears to function as a competitive (or mixed‐competitive) inhibitor of IDOs. [ABSTRACT FROM AUTHOR]

Polymicrobial co- and superinfections involving bacterial and fungal pathogens pose serious challenges for diagnosis and therapy, and are associated with elevated morbidity and mortality. However, the metabolic dynamics of bacterial–fungal interactions (BFI) and the resulting impact on disease outcome remain largely unknown. The fungus Aspergillus fumigatus and the bacterium Klebsiella pneumoniae are clinically important pathogens sharing common niches in the human body, especially in the lower respiratory tract. We have exploited an integrated multi-omics approach to unravel the complex and multifaceted processes implicated in the interspecies communication involving these pathogens in mixed biofilms. In this setting, A. fumigatus responds to the bacterial challenge by rewiring its metabolism, attenuating the translational machineries, and by connecting secondary with primary metabolism, while K. pneumoniae maintains its central metabolism and translation activity. The flexibility in the metabolism of A. fumigatus and the ability to quickly adapt to the changing microenvironment mediated by the bacteria highlight new possibilities for studying the impact of cross-communication between competing interaction partners. The data underscore the complexity governing the dynamics underlying BFI, such as pronounced metabolic changes mounted in A. fumigatus interacting with K. pneumoniae. Our findings identify candidate biomarkers potentially exploitable for improved clinical management of BFI. A multi-omics study highlights the flexibility in the metabolism of Aspergillus fumigatus in microenvironments co-shared with Klebsiella pneumoniae, uncovering potential biomarkers to enhance clinical care for polymicrobial infections. [ABSTRACT FROM AUTHOR]

Introduction: The gut microbiota is believed to be directly involved in the etiology and development of chronic liver diseases. However, the holistic characterization of the gut bacteriome, mycobiome, and virome in patients with chronic hepatitis B-related liver fibrosis (CHB-LF) remains unclear. Methods: In this study, we analyzed the multi-kingdom gut microbiome (i.e., bacteriome, mycobiome, and virome) of 25 CHB-LF patients and 28 healthy individuals through whole-metagenome shotgun sequencing of their stool samples. Results: We found that the gut bacteriome, mycobiome, and virome of CHB-LF patients were fundamentally altered, characterized by a panel of 110 differentially abundant bacterial species, 16 differential fungal species, and 90 differential viruses. The representative CHB-LF-enriched bacteria included members of Blautia_A (e.g., B. wexlerae , B. massiliensis , and B. obeum), Dorea (e.g., D. longicatena and D. formicigenerans), Streptococcus , Erysipelatoclostridium , while some species of Bacteroides (e.g., B. finegoldii and B. thetaiotaomicron), Faecalibacterium (mainly F. prausnitzii), and Bacteroides_A (e.g., B. plebeius_A and B. coprophilus) were depleted in patients. Fungi such as Malassezia spp. (e.g., M. japonica and M. sympodialis), Candida spp. (e.g., C. parapsilosis), and Mucor circinelloides were more abundant in CHB-LF patients, while Mucor irregularis , Phialophora verrucosa , Hortaea werneckii, and Aspergillus fumigatus were decreases. The CHB-LF-enriched viruses contained 18 Siphoviridae , 12 Myoviridae , and 1 Podoviridae viruses, while the control-enriched viruses included 16 Siphoviridae , 9 Myoviridae , 2 Quimbyviridae , and 1 Podoviridae_crAss-like members. Moreover, we revealed that the CHB-LF-associated gut multi-kingdom signatures were tightly interconnected, suggesting that they may act together on the disease. Finally, we showed that the microbial signatures were effective in discriminating the patients from healthy controls, suggesting the potential of gut microbiota in the prediction of CHB-LF and related diseases. Discussion: In conclusion, our findings delineated the fecal bacteriome, mycobiome, and virome landscapes of the CHB-LF microbiota and provided biomarkers that will aid in future mechanistic and clinical intervention studies. [ABSTRACT FROM AUTHOR]

Background: This study aimed to assess the diagnostic and prognostic value of Aspergillus-specific IgG (Asp-IgG) for invasive pulmonary aspergillosis (IPA) in non-neutropenic non-hematologic patients. Methods: Between November 2019 and February 2022, we recruited 40 non-neutropenic, non-hematologic IPA patients from Taiwan and measured serum Asp-IgG levels using Phadia, Thermofisher. A positive Asp-IgG test was defined as a level > 40 mgA/L. We evaluated the association between Asp-IgG levels and overall survival, as well 90-day mortality rate of IPA patients. Results: Of the 40 participants, 11 (27.5%) tested positive for Asp-IgG, while 16 (40%) had positive galactomannan antigen (optical density > 1). Higher Asp-IgG levels were associated with improved overall survival (HR: 0.22, 95% CI: 0.05–0.99, p = 0.035) in multivariable Cox regression. The overall 90-day mortality rate was 65% (26/40). We found that patients with low Asp-IgG levels (≤ 40 mgA/L) had a borderline higher 90-day mortality rate compared to patients with high Asp-IgG levels (OR: 3.15, 95% CI: 0.75–13.28, p = 0.118). Stratifying by serum galactomannan and Aspergillus IgG levels, patients with elevated serum GM and low Asp-IgG had the highest 90-day mortality (80%, 8/10), followed by patients with low serum GM and low Asp-IgG (68.4%, 13/19). Conclusions: Asp-IgG was positive in approximately one-fourth of non-neutropenic IPA patients. Asp-IgG may hold potential as a clinical prognostic factor for IPA. Further studies are required to validate this finding. [ABSTRACT FROM AUTHOR]

Aspergillus fumigatus can cause invasive pulmonary aspergillosis (IPA). Fungicidal azoles and fungistatic caspofungin (CAS) are the first- and second-line therapies, respectively, used to treat IPA. Treatment of A. fumigatus with CAS or micafungin induces the production of the oxylipin 5,8-diHODE by the fungal oxygenase PpoA. For this article, we investigated the influence of ppo genes, which encode the fatty acid oxygenases responsible for oxylipin biosynthesis, on CAS tolerance. The influence of PpoA and PpoC on CAS tolerance is mediated by MpkA phosphorylation and protein kinase A (PKA) activity. RNAseq transcriptional profiling and the label-free quantitative proteomics of the ppoA and ppoC mutants showed that differentially expressed genes and proteins are related to secondary metabolites and carbohydrate metabolism. We also characterized two clinical isolates, CM7555 and IFM61407, which decrease and increase susceptibility to CAS, respectively. CM7555 does not exhibit increased oxylipin production in the presence of CAS but oxylipin induction upon CAS exposure is increased in IFM61407, suggesting that oxylipins are not the only mechanism involved in CAS tolerance in these isolates. Upon CAS exposure, CM7555 has higher MpkA phosphorylation and PKA activity than IFM61407. Our results reveal the different aspects and genetic determinants involved in A. fumigatus CAS tolerance. [ABSTRACT FROM AUTHOR]

Background: Aspergillosis is a fungal disease caused by the inhalation of fungal spores of the genus Aspergillus spp. This fungus mainly affects the lungs but can spread and infect the maxillofacial region through the bloodstream or inoculation of the fungus after extraction or endodontic treatment, especially in the upper posterior teeth. The disease has nonspecific clinical manifestations that hinder its early diagnosis. Although the Polymerase Chain Reaction (PCR) technique holds promise as a diagnostic tool for aspergillosis, anatomopathological analysis services do not routinely adopt this method. Objectives: Therefore, the present study aimed to evaluate the applicability of PCR and standardise the techniques of preparation of biological samples for the detection of the three species: Aspergillus niger, Aspergillus fumigatus and Aspergillus flavus. Methods: Six samples of formalin-fixed, paraffin-embedded tissue (FFPE) with a histopathological diagnosis suggestive of aspergillosis were investigated using PCR. As a positive control for the PCR reaction, morphologically and genetically characterized cultures were used, with their sequences deposited at NCBI under accession codes MW837777 (A. fumigatus) and MW837779 (A. niger). The A. flavus culture used is reference RC 2053. Results: Four of the six samples evaluated were positive for Aspergillus spp., of which one was co-infected with A. fumigatus and A. flavus species, while two others were positive only for A. flavus, and one sample was positive only for A. fumigatus. Conclusions: These findings suggest that PCR can be used as an auxiliary method for diagnosing aspergillosis. However, this was a pilot study, and expansion of the sample size and the evaluation of PCR in comparison with other diagnostic tests for aspergillosis are essential to determine the accuracy of the method. [ABSTRACT FROM AUTHOR]