ABSTRACT Banana Fusarium wilt (BFW), caused by Fusarium oxysporum f. sp. cubense (Foc), poses a major challenge to the worldwide banana industry. Fungal microRNA-like small RNAs (milRNAs) play crucial roles in regulating fungal growth, conidiation, development, and pathogenicity. However, the milRNAs and their functions in the pathogenesis of Foc remain poorly understood. In this study, we employed high-throughput sequencing and bioinformatics to profile Foc sRNAs during both pure culture and early infection stages. Our analysis identified six milRNAs exhibiting significantly upregulated expression at the initial Foc infection. Of these, milR106’s biogenesis was found to be Dicer-dependent, whereas milR87, milR133, milR138, and milR148 were associated with Dicer and Argonaute proteins. Genetic manipulation and phenotype analysis confirmed that milR106 is crucial for Foc virulence by regulating conidiation, hydrogen peroxide sensitivity, and infective growth. Gene Ontology analysis of milRNA targets in the banana genome revealed enrichment in defence response to fungus and cellular response to hypoxia, implying the importance of these target genes in response to pathogen infection. In conclusion, our sRNA profiling of Foc identified several infection-induced milRNAs. The corresponding results provide valuable molecular targets for the development of an efficient strategy to control BFW.

ABSTRACT The combination of low temperatures, oligotrophic conditions, high altitude, and varying salinity in Tibetan Plateau lakes endows them with a wealth of distinctive fungal resources. This study aimed to investigate the diversity of culturable fungi in sediment and water samples collected from six lakes located on the Tibetan Plateau at elevations above 4,500 m. A total of 843 fungal strains were isolated by dilution plate method using four different media. Initial ITS analyses revealed that they belong to 156 species across 83 genera, spanning 50 families, 26 orders, 12 classes, and 6 phyla. Further morphological and multi-locus phylogenetic analyses were conducted, resulting in the formal descriptions of a new genus, Xizangia, and seven new species, including Alternaria xizangensis, Emericellopsis ovoidea, Myceliophthora xizangica, Preussia cylindricalis, Preussia sedimenticola, Pseudeurotium sedimenticola, and Xizangia sedimenticola. This research provides insights into the biodiversity of culturable fungi in the unique and extreme ecosystem, shedding light on the potential discovery of novel species and genera.

ABSTRACT The family Diatrypaceae is a less well-known group within the order Xylariales (Ascomycota). Initially, the focus on its metabolites was related to the pathogenicity of one of its members, Eutypa lata. To date, a total of 254 natural products have been identified from Diatrypaceae strains. These compounds include terpenoids, sterols, polyketones, phenols, and acetylene aromatic compounds, which have shown anticancer, cytotoxic, anti-inflammatory, antimicrobial, and antiviral activities. The complex and diverse structural types, along with the diverse bioactivities, highlight the potential of Diatrypaceae as a valuable source of bioactive natural products. In this review, a deep analysis of the biosynthesis of pimarane diterpenes and scoparasin-type cytochalasins is provided, coupled with a compilation of the biosynthetic pathways of aromatic acetylene compounds in filamentous fungi. This comprehensive review not only enhances our understanding of the natural product chemistry, biological activities, and biosynthesis of secondary metabolites from the Diatrypaceae family but also promotes the exploitation and development of important bioactive compounds and potential strains.

ABSTRACT Elucidating the mechanisms underlying antifungal resistance in Aspergillus fumigatus, discovering new antifungal targets, and developing drugs to inhibit resistance are the key approaches to treating A. fumigatus infections. Here, we investigated the function of ctf1 (AFUA_1G03800), a gene encoding a C6 transcription factor. Homologous recombination replacement technology was employed to construct ctf1-knockout and revertant strains. Fungal morphological observations revealed that the growth of the knockout strain was slower, showing fewer conidia. The minimum inhibitory concentration of triazoles was determined by performing the E-test and by using the micro-liquid-based dilution method. The results indicated that ctf1 deletion decreased the susceptibility of A. fumigatus to voriconazole by 2-fold. The decreased antifungal sensitivity of Δctf1 can be attributed to the increased ergosterol content and the overexpression of mdr1, mdr2, and mdr4. Thus, our results on the function of ctf1 contribute to the elucidation of the mechanisms underlying A. fumigatus resistance and the factors associated with A. fumigatus virulence.

ABSTRACT Leccinum scabrum (Bull.) Gray (Boletaceae) is an edible mycorrhizal species with potential application interest due to its food and medicinal properties. A field investigation carried out during summer in the Białowieża Primeval Forest, located along the border between Belarus and Poland allowed to collect samples for chemical composition analysis and antibacterial activity evaluation. Mushroom extracts were prepared with microwave-assisted as well as ultrasound-assisted extraction techniques (UAE and MAE). The analysis of a dry sample of L. scabrum showed a significant content of vitamins and minerals and also a remarkable content of carbohydrates, protein, dietary fibre, total sugars, total free amino acids, and polyunsaturated fatty acids. The antibacterial activity of L. scabrum aqueous extracts showed inhibitory activity against all tested bacteria. In general, MAE extract exhibits a higher inhibition activity against Listeria monocytogenes ATCC 19114. As regards the Minimum Inhibitory Concentration (MIC) values, the high antibacterial activity of MAE extract was detected for L. monocytogenes ATCC 19114 and Escherichia coli ATCC 25922. Regarding UAE, high antibacterial activity was detected for Salmonella enterica ATCC 13076 and L. monocytogenes ATCC 19114. Based on data hereby reported, L. scabrum is a culinary-medicinal mushroom with a promising potential use as a high-quality food and nutraceutical mycological resource.

ABSTRACT Understanding the composition and community of airborne mycobiota associated with fungal diseases was critical for mushroom production and disease control. In this study, we first investigated airborne fungi concentrations in different function areas of a Chinese shiitake factory. Then, high-throughput sequencing was employed to characterise the airborne fungal compositions and communities of this factory during high and low incidence seasons of shiitake artificial log rot disease (SLRD). The lowest concentration of culturable airborne fungi was observed in spawn-running greenhouse (250–450 CFU/m3), while the airborne fungi concentrations in cultivation greenhouses were up to 7,000–8,500 CFU/m3. The airborne fungal communities across distinct function areas showed convergence. The four major mushroom contaminants, Trichoderma, Penicillium, Cladosporium, and Aspergillus were the stable core fungi. Seasonal shifts in compositions, abundances, and communities of airborne fungi were systematically analysed and found to be associated with SLRD. Compared with the SLRD low incidence season, the airborne fungal communities were rich but uneven in the SLRD high incidence season, in which Trichoderma was dominant. Further analysis indicated that the favourable temperature and humidity caused the proliferation of Trichoderma and then affected the fungal communities, which presented an SLRD-seasonal variation. SLRD incidence could be significantly reduced by reasonably increasing the ambient temperature. For the first time, we comprehensively characterised the dynamics of airborne fungal communities across the SLRD occurrence in the shiitake factory. Findings here also provided valuable information for fungal exposures in the mushroom industry.

ABSTRACT Species of Micropsalliota generally grow in the tropics and are characterised by small, slender basidiomes, brown basidiospores, and cheilocystidia that vary in shape with capitate or subcapitate apex, and pigmented pileipellis. Based on morphological characters and molecular evidence, here we describe seven new species from southern China, viz. Micropsalliota ferruginea, M. fimbriata, M. gigaspora, M. longicystis, M. nana, M. squarrosa, and M. umbonata. Micropsalliota appendiculata, a species recently described from Vietnam, was first recorded in China. The Maximum likelihood and Bayesian analyses based on multi-locus sequence datasets (the nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2, nrITS; the D1–D2 domains of nuc 28S rDNA, LSU; partial sequences of the most variable region of the second-largest subunit of RNA polymerase II, rpb2, and a portion of the translation-elongation factor 1-α, tef1) shows that the genus is separated into 11 major clades and subclades. To aid in diagnosis, a key to 32 species of Micropsalliota in China is provided.

ABSTRACT Coprinellus disseminatus and other morphologically similar species are widely dispersed worldwide and are commonly referred to as “fairy inkcap”. Based on the molecular phylogenetic study and morphological observation, a thorough investigation was carried out utilising 74 collections of related species that were gathered from seventeen provinces and five Chinese fungaria between 1998 and 2023 and revealed 11 lineages of “fairy inkcap”, nine of which were found in China, and which belonged to the two genera Coprinellus and Tulosesus. In sect. Disseminati, genetic diversities (π), and fixation index (Fst) amongst lineages were computed, and a haplotype-based network was established to ascertain the relationships amongst each clade. A new section of Coprinellus, sect. Aureodisseminati, were discovered. In addition, four new species (C. aureodisseminatus, C. austrodisseminatus, C. parcus, and C. velutipes), a new subspecies of C. disseminatus, a new combination (Tulosesus pseudodisseminatus), the first discovery of epigamous type of C. magnoliae and a new record to China (T. subdisseminatus) were also identified and thoroughly described with accompanying illustrations. Their differences in macro- and micro-features, as well as their character sequence, were discussed.

ABSTRACT China has a huge area of diverse landscapes and is believed to conceive incredibly high fungal diversity. To systematically and promptly report Chinese fungal species, we initiate the series of Catalogue of fungi in China here. In the first paper of this series, we focus on plant-inhabiting fungi. A total of 33 new taxa are described all over China. These taxa include two new genera, viz. Cremeoefibula and Nothopucciniastrum, 18 new species, viz. Annulohypoxylon lancangensis, Ascotaiwania coffeae, Clitocella neofallax, Coleopuccinia yunnanensis, Cremeoefibula hengduanensis, Crepidotus furcaticystidiosus, C. tomentellus, Diachea macroverrucosa, Helicogloea hangzhouensis, Hyalopsora caprearum, Nemania polymorpha, Phanerochaetella austrosinensis, Physalacria tianzhongshanensis, Setophaeosphaeria panlongensis, Subulicystidium boreale, Trechispora subaraneosa, Vikalpa dujuanhuensis, and Xylaria pteridicola, and 13 new combinations, viz. Nothopucciniastrum actinidiae, N. boehmeriae, N. coriariae, N. corni, N. coryli, N. fagi, N. kusanoi, N. hikosanense, N. hydrangeae-petiolaris, N. miyabeanum, N. styracinum, N. tiliae, and N. yoshinagae. The morphological characteristics and phylogenetic evidence are used to support the establishment of these new taxa and the accuracy of their taxonomic placements. We hope that the series of Catalogue of fungi in China will contribute to Chinese fungal diversity and promote the significance of recording new fungal taxa from China.

ABSTRACT Fungal infections caused by Candida albicans have posed a persistent threat to human health. Existing clinical antifungal drugs are constrained by issues such as drug resistance and side effects. Compounds containing maleimide rings have been verified to possess antifungal properties, although the specific molecular mechanisms by which they exert this activity have yet to be fully understood. A total of 40 compounds containing maleimide rings were synthesised in the present study, and 12 derivatives that possessed antifungal properties were subsequently identified. The maleimide compound 5 (MPD) with the most potent activity demonstrated fungicidal action at a concentration that was twice as potent as the minimal inhibitory concentration and effectively prevented the formation of biofilms. Furthermore, the mechanistic studies revealed that MPD interfered with iron ion homoeostasis by reducing intracellular iron concentration inside cells, which led to the inhibition of ergosterol biosynthesis and increased cell membrane permeability, resulting in the leakage of intracellular trehalose. In addition, MPD was observed to perturb cell wall biosynthesis by reducing the activity of chitin synthase. Moreover, MPD was found to demonstrate therapeutical efficacy in vivo when assessed using a Caenorhabditis elegans-C. albicans infection model.