Emerging Fungal Infections: from the Fields to the Clinic, Resistant Aspergillus fumigatus and Dermatophyte Species: a One Health Perspective on an Urgent Public Health Problem

Characteristics of Chrysosporium spp. Pathogens Causing Skin Mycoses in Horses

Equine skin mycoses are a significant concern in Kazakhstan's livestock industry due to the country's historical livestock farming practices, the development of equestrian sports, and food traditions. Skin infections are among the most common fungal infections in horses. Emerging pathogens of equine dermatophytosis include keratinophilic Chrysosporium spp., which can degrade and metabolize keratin found in superficial tissues. This, combined with their thermotolerance, contributes to their pathogenicity. In this study, we investigated the biological properties and pathogenicity of two Chrysosporium strains isolated from equine skin lesions in northern and central Kazakhstan. Our findings showed that the Chrysosporium isolates caused a variety of clinically expressed skin lesions and exhibited cultural and morphological similarities to Trichophyton mentagrophytes. Genetic identification using ribosomal gene sequencing revealed 98.9% identity with Chrysosporium kreiselii and Chrysosporium zonatum sequences in both cases. The C. kreiselii strain caused pronounced skin lesions typical of classic dermatomycoses, demonstrated both keratinophilic and keratinolytic properties, and showed resistance to antifungal drugs. In contrast, the C. zonatum strain, which caused atypical lesions such as dandruff and seborrhea, was more sensitive to antifungal agents and exhibited keratinophilic properties. Our results highlight the emergence of new pathogenic Chrysosporium strains responsible for skin pathology in horses in Kazakhstan. We recommend that the identification of Chrysosporium skin infections in horses in Kazakhstan be followed by a comprehensive retrospective analysis of newly identified pathogens, including a full characterization of their pathogenicity.

The Significance of Fungal Specialized Metabolites in One Health Perspectives

Among the emerging threats in global health, fungal pathogens stand out as some of the most important, causing over 1.6 million deaths annually and destroying a third of all food crops each year, exacerbating food insecurity and economic losses. Climate change further amplifies the threat by enabling pathogenic fungi to survive at mammalian temperatures, increasing risks of zoonotic transmission and antifungal resistance. In this context, interdisciplinary research, particularly the One Health approach, is crucial for understanding the evolution of fungal resistance and improving diagnostic and therapeutic tools. Drawing lessons from agriculture, where integrated pest management strategies successfully mitigate fungal threats, could offer new ways to tackle fungal infections in humans. Advanced metabolomics and diagnostics, including fungal metabolites as biomarkers, hold promise for early detection and personalized treatment. Collaborative efforts between medicine, veterinary science, and plant pathology are essential to develop new antifungal drugs and improve clinical management of fungal diseases, fostering a more resilient global health system.

Global Dermatophyte Infections Linked to Human and Animal Health: A Scoping Review

Dermatophytes are commonly encountered pathogens in clinical practice causing superficial infections of the skin, hair, and nails. These pathogens are often found on animals such as livestock (e.g., cattle, rabbits) and pets (e.g., cats, hedgehogs) that can lead to spillover infections in human populations. Here, we reviewed published reports (2009-2024) of dermatophyte infections in animals and in humans with a history of animal contact. A literature search was completed in October 2024 using PubMed, Embase (Ovid), and Web of Science (Core Collection), which identified 250 articles. Generally, dermatophytes tend to infect younger animals with long hair and exhibit a species-specific host range. Microsporum canis was the most commonly reported species-linked to cats-that can cause tinea capitis, especially concerning the development of kerion in children. Trichophyton verrucosum is strongly associated with cattle. The Trichophyton mentagrophytes complex shows a diverse range of animal hosts, with rabbits being most frequently reported; however, T. mentagrophytes var. erinacei is almost exclusively isolated from hedgehogs, and T. mentagrophytes var. benhamiae is more commonly found on rodents (e.g., guinea pigs). Lastly, the geophilic Nannizia gypsea has been isolated from both dogs and cats. Managing dermatophyte zoonoses is an ongoing challenge, as healthcare providers may empirically treat with corticosteroids or antibacterial agents due to its atypical inflammatory appearance. Evidence of in vitro resistance against griseofulvin and fluconazole has been documented in multiple zoonotic dermatophyte species. Resistance development against terbinafine and itraconazole is also a possibility, although the number of reports is scarce. Under the principles of the One Health approach, research on human fungal diseases should take animal and environmental factors into account. A renewed call for increased testing efforts is warranted.

Molecular epidemiology of dermatophytosis in Golestan, Iran: A cross-sectional study

Keratinophilic fungi, or dermatophytes, are recognized as the predominant fungal agents responsible for superficial skin diseases globally. The identification of species of dermatophytes is crucial for both therapeutic and epidemiological considerations. The primary objective of the present study was to investigate the epidemiology of dermatophytosis among patients who sought medical attention at the medical mycology laboratory in Golestan province. This study aims to provide a comprehensive assessment and analysis of fungal infections occurring in many anatomical regions of the human body and the several diagnostic procedures employed to confirm such infections. In this investigation, 255/550 clinical specimens were obtained from patients thought to have dermatophytosis. All samples underwent direct microscopy and culture examinations. DNA extraction from a fungal colony was conducted using the phenol-chloroform method. Then, the ITS1-5.8s-ITS2 region of ribosomal DNA (rDNA) was amplified by the universal fungal primers ITS1 and ITS4 and digested with enzymes Mval. In the current study, 255 patients (46.3 %) were positive for dermatophytosis. Of these, 38.4 % were male and 61.6 % female. The most common dermatophytes isolated were Trichophyton mentagrophytes/interdigitale (86.7 %) and Trichophyton rubrum (5.1 %), respectivly. The frequency of other species were Trichophyton tonsurans (3.1 %), Microsporum canis (2.7 %), Trichophyton benhamiae (0.8 %), Trichophyton violaceum (0.8 %), Trichophyton quinckeanum (0.4 %), and Microsporum ferrugineum (0.4 %). The findings indicated that Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) is an expeditious and dependable technique for diagnosing dermatophytes. In combination with morphological analysis, PCR-RFLP is recommended as a valuable approach for identifying dermatophytes in diagnostic contexts, particularly within clinical and epidemiological settings.

Comprehensive Review of Environmental Surveillance for Azole-Resistant Aspergillus fumigatus: A Practical Roadmap for Hospital Clinicians and Infection Control Teams

As azole-resistant Aspergillus fumigatus emerges globally, healthcare facilities face mounting challenges in managing invasive aspergillosis. This review synthesizes worldwide azole resistance data to reveal profound regional variability, demonstrating that findings from other regions cannot be directly extrapolated to local settings. Consequently, hospital-level environmental surveillance is crucial for tailoring interventions to local epidemiology and detecting resistant strains in real-time. We outline practical approaches-encompassing sampling site prioritization, diagnostic workflows (culture-based and molecular), and PDCA-driven continuous improvement-so that even resource-limited facilities can manage resistant isolates more effectively. By linking real-time surveillance findings with clinical decisions, hospitals can tailor antifungal stewardship programs and swiftly adjust prophylaxis or treatment regimens. Our approach aims to enable accurate, ongoing evaluations of emerging resistance patterns, ensuring that institutions maintain efficient and adaptive programs. Ultimately, we advocate for sustained, collaborative efforts worldwide, where facilities adapt protocols to local conditions, share data through international networks, and contribute to a global knowledge base on resistance mechanisms. Through consistent application of these recommendations, healthcare systems can better preserve azole efficacy, safeguard immunocompromised populations, and refine infection control practices in the face of evolving challenges.

Terbinafine-Resistant Dermatophytes Isolated in Japan

An epidemiological study of terbinafine (TBF)-resistant dermatophytes was conducted in 2023 as a follow-up to our 2020 and 2022 surveys. Dermatophytes were isolated in 2023 from the same dermatology clinics in Tokyo, Saitama, Shizuoka, and Kumamoto, Japan, as in the previous studies. In total, 311 isolates (122 Trichophyton interdigitale isolates, 1 Trichophyton indotineae isolate, and 188 Trichophyton rubrum isolates) were obtained from 311 human cases of dermatophytosis (195 tinea pedis cases, 54 tinea unguium cases, 28 tinea corporis cases, 27 tinea cruris cases, and 7 tinea manuum cases). Ten strains (1 T. interdigitale strain and 9 T. rubrum strains) were found to be resistant to TBF, and susceptible to efinaconazole, itraconazole, luliconazole, and ravuconazole. The isolation rate of TBF-resistant strains was 2.3% in 2020, 1.4% in 2022, and 3.2% in 2023. We determined the sequences of the squalene epoxidase-encoding gene in 10 TBF-resistant strains, and found that all strains harbored missense and/or deletion mutations. These results indicate that the prevalence of TBF-resistant dermatophytes has increased when compared to the previous studies.

Epidemiology and Antifungal Susceptibilities of Clinically Isolated Aspergillus Species in Tertiary Hospital of Southeast China

Background and Aim

Infection caused by Aspergillus species poses a growing global concern, yet their prevalence in Southeast China lacks comprehensive documentation. This retrospective analysis aims to elucidate the epidemiological role and antifungal susceptibilities of Aspergillus species at Huashan Hospital of Fudan University, Shanghai, China.

Methods

Data spanning from 2018 to 2022, encompassing demographic, clinical, and laboratory information on Aspergillus species isolates were analyzed. The isolates were subjected to susceptibility testing using YeastOneTM broth microdilution system.

Results

A total of 253 Aspergillus isolates were identified, with A. fumigatus (57.71%) being the predominant species, followed by A. niger (26.88%), A. flavus (10.67%), and A. terreus (3.95%). Notably, the highest number of isolates originated from the Department of Infectious Disease (28.06%), with sputum (54.94%) being the primary source of isolation, where A. fumigatus was the dominant species. Gastrointestinal disorder (23.90%), hepatic disorder (9.09%), and diabetes (8.30%) were identified as the most prevalent underlying conditions, with A. fumigatus being the most abundant species in each case, accounting for 65.08%, 82.60%, and 73.91%, respectively, followed by A. flavus. Non-wild-type (NWT) Aspergillus isolates exhibited higher resistance against amphotericin B (AMB) compared to triazoles. Specifically, A. fumigatus showed greater resistance to AMB, with only 23.28% of isolates being susceptible, while the majority of isolates were susceptible to triazoles like itraconazole (ITR) and posaconazole (POS). POS demonstrated the highest efficacy against all species. Sequencing revealed mutations in the promoter region of the cyp51A gene and at positions Y121F and E247K in A, fumigatus which confer resistance to ITR, voriconazole (VRC), and POS.

Conclusion

These findings contribute to a better understanding of the epidemiology and antifungal resistance pattern of Aspergillus species in the region, providing valuable insights for the management of Aspergillus-related infections.

The Likelihood of Resistant Tinea Capitis Caused by Hortaea Werneckii: A Case Report

This case study illustrates a 24-year-old Chinese man who presented with tinea capitis associated with a fungal infection. He was administered a therapeutic regimen consisting of terbinafine, ketoconazole cream, and miconazole shampoo for 2 months. However, the symptoms recurred 3 months after the treatment ended. Fungal culture and sequencing confirmed the infection of Hortaea werneckii. Drug sensitivity testing showed that the infecting strain of the patient remained sensitive to the five commonly used antifungal drugs in vitro. While most cases infected by Hortaea werneckii present with Tinea nigra, the possibility of Hortaea werneckii infection should be considered in patients with tinea capitis living in coastal cities.

Development of treatment strategies by comparing the minimum inhibitory concentrations and minimum fungicidal concentrations of azole drugs in dermatophytes

We compared the minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of azoles in antifungal drug-susceptible, terbinafine-resistant, and lowly itraconazole (ITCZ)-susceptible strains of dermatophytes. To assess the MICs of ITCZ, ravuconazole (RVCZ), efinaconazole (EFCZ), and luliconazole (LUCZ) in the isolates, broth microdilution assays were performed based on the Clinical and Laboratory Standards Institute M38-A2 guidelines with modifications. After the assays for determining the MICs, the inoculum suspensions in wells were resuspended, then 10 μL of the growth solution in each well was inoculated onto potato dextrose agar with the use of a pipette. After 7 days of incubation at 28°C, the MFCs were determined as the lowest concentration of a drug that allowed the growth of colonies on the potato dextrose agar. The MICs in the dermatophytes were <0.03 to >32 mg/L for ITCZ, <0.03 to 4 mg/L for RVCZ, <0.03 to 2 mg/L for EFCZ, and <0.03 mg/L for LUCZ. The MFCs in the dermatophytes were 1 to >32 mg/L for ITCZ, 0.06 to >32 mg/L for RVCZ, <0.03 to 4 mg/L for EFCZ, and <0.03 to 2 mg/L for LUCZ. If the drug susceptibility test shows that the fungi are resistant to the drug, the treatment can be changed to a susceptible drug in advance, or if the fungi are low-susceptible, the treatment can be done with the recognition that it may require a longer treatment period than usual.

Beyond the Charge: Interplay of Nanogels' Functional Group and Zeta-Potential for Antifungal Drug Delivery to Human Pathogenic Fungus Aspergillus Fumigatus

The ubiquitous mold Aspergillus fumigatus (A. fumigatus) is one of the main fungal pathogens causing invasive infections in immunocompromised humans. Conventional antifungal agents exhibit limited efficacy and often cause severe side effects. Nanoparticle-based antifungal delivery provides a promising alternative, which can increase local drug concentration; while, mitigating toxicity, thereby enhancing treatment efficacy. Previous research underscores the potential of poly(glycidol)-based nanogels (NG) with negative surface charge as carriers for delivering antifungals to A. fumigatus hyphae. In this study, NG is tailored with 2-carboxyethyl acrylate (CEA) or with phosphoric acid 2-hydroxyethyl acrylate (PHA). It is discovered that quenching with PHA clearly improves the adhesion of NG to hyphal surface and the internalization of NG into the hyphae under protein-rich conditions, surpassing the outcomes of non-quenched and CEA-quenched NG. This enhancement cannot be solely attributed to an increase in negative surface charge but appears to be contingent on the functional group of the quencher. Further, it is demonstrated that itraconazole-loaded, PHA-functionalized nanogels (NGxPHA-ITZ) show lower MIC in vitro and superior therapeutic effect in vivo against A. fumigatus compared to pure itraconazole. This confirms NGxPHA as a promising antifungal delivery system.

Climate change and resilience for antimicrobial stewardship and infection prevention

PURPOSE OF REVIEW

This review covers recent research regarding the challenges posed by climate change within the areas of antimicrobial stewardship and infection prevention, and ways to build resiliency in these fields.

RECENT FINDINGS

Infectious disease patterns are changing as microbes adapt to climate change and changing environmental factors. Capacity for testing and treating infectious diseases is challenged by newly emerging diseases, which exacerbate challenges to antimicrobial stewardship and infection prevention.Antimicrobial resistance is accelerated due to environmental factors including air pollution, plastic pollution, and chemicals used in food systems, which are all impacted by climate change.Climate change places infection prevention practices at risk in many ways including from major weather events, increased risk of epidemics, and societal disruptions causing conditions that can overwhelm health systems. Researchers are building resilience by advancing rapid diagnostics and disease modeling, and identifying highly reliable versus low efficiency interventions.

SUMMARY

Climate change and associated major weather and socioeconomic events will place significant strain on healthcare facilities. Work being done to advance rapid diagnostics, build supply chain resilience, improve predictive disease modeling and surveillance, and identify high reliability versus low yield interventions will help build resiliency in antimicrobial stewardship and infection prevention for escalating challenges due to climate change.

Azole resistance in Aspergillus fumigatus- comprehensive review

Aspergillus fumigatus is a ubiquitous filamentous fungus commonly found in the environment. It is also an opportunistic human pathogen known to cause a range of respiratory infections, such as invasive aspergillosis, particularly in immunocompromised individuals. Azole antifungal agents are widely used for the treatment and prophylaxis of Aspergillus infections due to their efficacy and tolerability. However, the emergence of azole resistance in A. fumigatus has become a major concern in recent years due to their association with increased treatment failures and mortality rates. The development of azole resistance in A. fumigatus can occur through both acquired and intrinsic mechanisms. Acquired resistance typically arises from mutations in the target enzyme, lanosterol 14-α-demethylase (Cyp51A), reduces the affinity of azole antifungal agents for the enzyme, rendering them less effective, while intrinsic resistance refers to a natural resistance of certain A. fumigatus isolates to azole antifungals due to inherent genetic characteristics. The current review aims to provide a comprehensive overview of azole antifungal resistance in A. fumigatus, discusses underlying resistance mechanisms, including alterations in the target enzyme, Cyp51A, and the involvement of efflux pumps in drug efflux. Impact of azole fungicide uses in the environment and the spread of resistant strains is also explored.

Novel antifungals and treatment approaches to tackle resistance and improve outcomes of invasive fungal disease

SUMMARYFungal infections are on the rise, driven by a growing population at risk and climate change. Currently available antifungals include only five classes, and their utility and efficacy in antifungal treatment are limited by one or more of innate or acquired resistance in some fungi, poor penetration into "sequestered" sites, and agent-specific side effect which require frequent patient reassessment and monitoring. Agents with novel mechanisms, favorable pharmacokinetic (PK) profiles including good oral bioavailability, and fungicidal mechanism(s) are urgently needed. Here, we provide a comprehensive review of novel antifungal agents, with both improved known mechanisms of actions and new antifungal classes, currently in clinical development for treating invasive yeast, mold (filamentous fungi), Pneumocystis jirovecii infections, and dimorphic fungi (endemic mycoses). We further focus on inhaled antifungals and the role of immunotherapy in tackling fungal infections, and the specific PK/pharmacodynamic profiles, tissue distributions as well as drug-drug interactions of novel antifungals. Finally, we review antifungal resistance mechanisms, the role of use of antifungal pesticides in agriculture as drivers of drug resistance, and detail detection methods for antifungal resistance.

High Prevalence of Terbinafine Resistance Among Trichophyton mentagrophytes/T. interdigitale Species Complex, a Cross-Sectional Study from 2021 to 2022 in Northern Parts of Iran

Treatment-resistant dermatophytosis caused by the members of the Trichophyton mentagrophytes/Trichophyton interdigitale species group (TMTISG) is increasing worldwide. We aimed to determine the prevalence of TMTISG in patients with dermatophytosis in two centers from north of Iran and detect the possible mutations in the squalene epoxidase (SQLE) gene in relevant terbinafine (TRB) resistant pathogenic isolates. From November 2021 to December 2022, 1960 patients suspected to dermatophytosis and referred to two mycology referral laboratories in the north of Iran were included in the study. Identification of all dermatophyte isolates was confirmed by RFLP of rDNA internal transcribed spacer (ITS) regions. Antifungal susceptibility testing against five common antifungals using the CLSI-M38-A3 protocol was performed. The TMTISG isolates resistant to TRB, were further analyzed to determine the possible mutations in the SQLE gene. Totally, 647 cases (33%) were positive for dermatophytosis of which 280 cases (43.3%) were identified as members of TMTISG. These were more frequently isolated from tinea corporis 131 (44.56%) and tinea cruris 116 (39.46%). Of 280 TMTISG isolates, 40 (14.3%) were resistant to TRB (MIC ≥ 4 µg/mL), all found to be T. indotineae in ITS sequencing. In SQLE sequencing 34 (85%) of TRB-resistant isolates had coincident mutations of Phe397Leu and Ala448Thr whereas four and two isolates had single mutations of Phe397Leu and Leu393Ser, respectively. Overall, the resistance of Iranian TMTISG isolates to TRB greatly occurred by a mutation of Phe397Leu in the SQLE gene as alone or in combination with Ala448Thr. Nevertheless, for the occurrence of in vitro resistance, only the presence of Phe397Leu mutation seems to be decisive.

Studies on the in vitro mechanism and in vivo therapeutic effect of the antimicrobial peptide ACP5 against Trichophyton mentagrophytes

Trichophyton mentagrophytes is a zoophilic dermatophyte that can cause dermatophytosis in humans and animals. Antimicrobial peptides (AMPs) are considered as a promising agent to overcome the drug-resistance of T. mentagrophytes. Our findings suggest that cationic antimicrobial peptide (ACP5) not only possesses stronger activity against T. mentagrophytes than fluconazole, but also shows lower toxicity to L929 mouse fibroblast cells than terbinafine. Notably, its resistance development rate after resistance induction was lower than terbinafine. The present study aimed to evaluate the fungicidal mechanism of ACP5 in vitro and its potential to treat dermatophyte infections in vivo. ACP5 at 1 ×MIC completely inhibited T. mentagrophytes spore germination in vitro. ACP5 severely disrupts the mycelial morphology, leading to mycelial rupture. Mechanistically, ACP5 induces excessive ROS production, damaging the integrity of the cell membrane and decreasing the mitochondrial membrane potential, causing irreversible damage in T. mentagrophytes. Furthermore, 1% ACP5 showed similar efficacy to the commercially available drug 1% terbinafine in a guinea pig dermatophytosis model, and the complete eradication of T. mentagrophytes from the skin by ACP5 was verified by tissue section observation. These results indicate that ACP5 is a promising candidate for the development of new agent to combat dermatophyte resistance.

Exploring airborne fungal contaminations and air quality pollution in nine ancient stone temples, Surin, Thailand

This study provided crucial insights into the concentrations of airborne fungi, environmental parameters, and atmospheric pollution in Thailand's ancient stone temples. Airborne fungi were identified based on morphological characteristics. Airborne fungi, meteorological parameters, and atmospheric pollutants concurrently assessed during each sampling event, evaluating indoor/outdoor ratio. Prevalent genera included Penicillium (14.36%), Aspergillus (10.94%), Cladosporium (10.74%), Rhizopus (6.31%), and Fusarium (5.90%), with an average fungi concentration of 4884.46 ± 724.79 CFU/m3. Eighteen fungal species out of the 64 airborne fungi identified were well-known serious pathogenic agents, contributing not only to structural deterioration but also to human health. Significant variations were observed between indoor and outdoor environments and across diverse landscapes, particularly for PM10 (ranging from 43.47 to 121.31 µg/m3) and PM2.5 (ranging from 29.59 to 89.60 µg/m3), with intensive incense burning identified as a prominent source of indoor atmospheric pollution. Historical temples, particularly situated in urban areas, were identified as significant reservoirs of airborne fungi. Correlations between meteorological parameters and pollutants revealed strong associations. Furthermore, principal component analysis (PCA) and cluster analysis elucidated distinct patterns in airborne fungal concentrations and contaminations. This study analyzed environmental factors, pollutants, airborne fungi, and geographical variations from July 2020 to March 2021. Understanding prevalent genera, airborne fungi concentrations, pathogenic species, biodeterioration, and environmental dynamics provided strategies for improving indoor air quality and mitigating airborne fungal contamination in archaeological buildings worldwide.

Poacic Acid, a Plant-Derived Stilbenoid, Augments Cell Wall Chitin Production, but Its Antifungal Activity Is Hindered by This Polysaccharide and by Fungal Essential Metals

Climate and environmental changes have modified the habitats of fungal pathogens, inflicting devastating effects on livestock and crop production. Additionally, drug-resistant fungi are increasing worldwide, driving the urgent need to identify new molecular scaffolds for the development of antifungal agents for humans, animals, and plants. Poacic acid (PA), a plant-derived stilbenoid, was recently discovered to be a novel molecular scaffold that inhibits the growth of several fungi. Its antifungal activity has been associated with perturbation of the production/assembly of the fungal cell wall β-1,3-glucan, but its mode of action is not resolved. In this study, we investigated the antifungal activity of PA and its derivatives on a panel of yeast. PA had a fungistatic effect on S. cerevisiae and a fungicidal effect on plasma membrane-damaged Candida albicans mutants. Live cell fluorescence microscopy experiments revealed that PA increases chitin production and modifies its cell wall distribution. Chitin production and cell growth returned to normal after prolonged incubation. The antifungal activity of PA was reduced in the presence of exogenous chitin, suggesting that the potentiation of chitin production is a stress response that helps the yeast cell overcome the effect of this antifungal stilbenoid. Growth inhibition was also reduced by metal ions, indicating that PA affects the metal homeostasis. These findings suggest that PA has a complex antifungal mechanism of action that involves perturbation of the cell wall β-1,3-glucan production/assembly, chitin production, and metal homeostasis.

Long Amplification PCR (LA-PCR) Detection of Azole Resistant Trichophyton indotineae

Trichphyton indotineae, a species newly designated in 2020 independent of T. interdigitale, comprises highly terbinafine (TRF)-resistant dermatophytosis that is epidemic in North India and spreding to worldwide. Some clinical isolates of T. indotineae have been resistance both TRF and azoles that might be caused the treatment failure. To detect the azole resistance strains, we developed a long amplification PCR (LA-PCR) detection method for the tandem repeat of the CYP51B (encoding sterol 14a-demethylase gene) in T. indotineae. Contrasting the drug susceptibility test results with the LA-PCR results confirmed a trend toward low susceptibility to azole antifungal agents in strains with amplifications of 9.5 kbp or greater (3 or more copies of CYP51B). Our results suggest that the method could be detected rapidly of low-susceptibility strains to azole antifungal agents.

A New Genotype of Trichophyton quinckeanum with Point Mutations in Erg11A Encoding Sterol 14-α Demethylase Exhibits Increased Itraconazole Resistance

Trichophyton quinckeanum, the causative agent of mouse favus, has been responsible for several infections of animal owners in recent years and showed an infection peak around 2020 in Jena, Thuringia. The isolated T. quinckeanum strains from Thuringia differ in some positions of the ITS region compared to strains from the IHEM collection as well as to Trichophyton schoenleinii. All T. quinckeanum strains of the new genotype show up to a 100-fold increased itraconazole resistance as measured by microplate laser nephelometry (MLN) assays. Analysis of genes involved in Trichophyton indotineae azole resistance, such as Erg1, which encodes squalene epoxidase, and Erg11B, one of two copies of the sterol 14-α demethylase gene, show a 100% identity between the two T. quinckeanum genotypes. In contrast, Erg11A fragments differ in 15-nucleotide positions between both T. quinckeanum genotypes, resulting in the unique amino acid substitution Ala256Ser in resistant strains. The new T. quinckeanum genotype may have evolved through interspecies mating. Mating type analysis showed a nearly 100% identity of the minus type MAT1-1-1 fragment for all T. quinckeanum isolates. The closely related Trichophyton schoenleinii belongs to the plus mating type and has 100% identical fragments of Erg1 and Erg11B. Erg11A protein sequences of T. schoenleinii and T. quinckeanum showed increased diversity.

Chitinophaga pendula, sp. nov., from an air conditioner condensate drain line

A Gram-negative, rod-shaped and filamentous bacterium designated MD30BT was isolated from a biofilm hanging in water flowing from an air conditioner condensate drain line in Honolulu, Hawai'i. Based on 1517 nucleotides of the strain's 16S rRNA gene, its nearest neighbours are Chitinophaga rhizosphaerae T16R-86T (96.7 %), Chitinophaga caseinilytica S-52T (96.6 %), Chitinophaga lutea ZY74T (96.6 %), Chitinophaga niabensis JS13-10T (96.6 %) and Chitinophaga ginsengisoli Gsoil 052T (96.5 %). MD30BT cells are non-motile, strictly aerobic, and catalase and oxidase positive. Growth occurs between 10 and 45 °C. Major fatty acids in whole cells of MD30BT are 13-methyl tetradecanoic acid (34.1 %), cis-11-hexadecenoic acid (30.3 %), and 3-hydroxy, 15-methyl hexadecanoic acid (13.3 %). The quinone system contains predominantly menaquinone MK-7. The polar lipid profile contains the major lipids phosphatidylethanolamine, one unidentified lipid lacking a functional group, and two unidentified aminolipids. sym-Homospermidine is the major polyamine. The G+C content of the genome is 47.58 mol%. Based on phenotypic and genotypic differences between MD30BT and extant species in the Chitinophaga, we propose that MD30BT represents a new Chitinophaga species, for which the name Chitinophaga pendula sp. nov. is proposed to accommodate strain MD30BT as the type strain (DSM 112477T=NCTC 14606T).

Naringin from Coffee Inhibits Foodborne Aspergillus fumigatus via the NDK Pathway: Evidence from an In Silico Study

In the tropics, coffee has been one of the most extensively cultivated economic crops, especially Arabica coffee (Coffea arabica L.). The coffee pulp, which includes phytochemicals with a proven antifungal action, is one of the most insufficiently utilized and neglected byproducts of coffee refining. In the current experiment, we carried out in silico screening of the isolated Arabica coffee phytochemicals for antifungal activity against Aspergillus fumigatus: a foodborne fungus of great public health importance. As determined by the molecular docking interactions of the library compounds indicated, the best interactions were found to occur between the nucleoside-diphosphate kinase protein 6XP7 and the test molecules Naringin (-6.771 kcal/mol), followed by Epigallocatechin gallate (-5.687 kcal/mol). Therefore, Naringin was opted for further validation with molecular dynamic simulations. The ligand-protein complex RMSD indicated a fairly stable Naringin-NDK ligand-protein complex throughout the simulation period (2-16 Å). In ADME and gastrointestinal absorbability testing, Naringin was observed to be orally bioavailable, with very low intestinal absorption and a bioavailability score of 0.17. This was further supported by the boiled egg analysis data, which clearly indicated that the GI absorption of the Naringin molecule was obscure. We found that naringin could be harmful only when swallowed at a median lethal dose between 2000 and 5000 mg/kg. In accordance with these findings, the toxicity prediction reports suggested that Naringin, found especially in citrus fruits and tomatoes, is safe for human consumption after further investigation. Overall, Naringin may be an ideal candidate for developing anti-A. fumigatus treatments and food packaging materials. Thus, this study addresses the simultaneous problems of discarded coffee waste management and antifungal resistance to available medications.

Epidemiological study of antifungal-resistant dermatophytes isolated from Japanese patients

An epidemiological study of antifungal drug-resistant dermatophytes was conducted as a follow-up to our 2020 survey. Dermatophytes were isolated in 2022 from the same dermatology clinics as in the previous study. In total, 288 Trichophyton interdigitale and Trichophyton rubrum clinical isolates were obtained from 288 human cases of dermatophytosis in Tokyo, Saitama, Shizuoka, and Kumamoto, Japan. Four strains were found to be resistant to terbinafine (TRF) and susceptible to itraconazole (ITZ), luliconazole (LCZ), and ravuconazole (RVZ), and three other strains were found to be resistant to ITZ and susceptible to TRF, LCZ, and RVZ. We determined the sequences of the squalene epoxidase (SQLE)-encoding gene in the three TRF-resistant T. rubrum strains, and found that two strains harbored L393F missense mutations, and one strain harbored a F397L missense mutation. The results of the present study indicated that the prevalence of TRF-resistant dermatophytes has not increased since 2020. However, TRF-resistant T. interdigitale (L393F mutation) was isolated for the first time, indicating that attention should be paid to the presence of TRF-resistant T. interdigitale in the future. We also examined for the first time the epidemiology of ITZ-resistant T. rubrum in Japanese patients. Although the number of ITZ-resistant strains was not large, the results confirmed that ITZ-resistant T. rubrum strains do exist in Japanese patients.