Mycobiology最新文献

In this study, three novel fungal species belonging to the Nectriaceae family, Gliocladiopsis koreensis sp. nov., Ilyonectria koreensis sp. nov., and Mariannaea koreensis sp. nov., were discovered from soil samples collected at Iseung-ak Oreum on Jeju Island and the Upo Wetland in Changnyeong, Republic of Korea. They were confirmed as distinct species through molecular phylogenetic analyses using the ITS, TUB, Tef1, HIS3, and LSU sequences. Maximum-likelihood and Bayesian inference trees show that G. koreensis forms a sister clade with G. curvata, G. singaporiensis, and G. peggii, I. koreensis clusters closely with I. qitaiheensis and I. changbaiensis, and M. koreensis is phylogenetically related to M. atlantica, M. fusiformis, M. elegans var. punicea, and M. terricola. While all three new species exhibit unique morphological characteristics such as colony growth patterns, pigmentation, and microstructures that differentiate them from their closest relatives. The findings of these novel species contribute to the understanding of fungal diversity in these ecologically significant regions and highlight their potential applications in agriculture, nutrient cycling, and environmental restoration.

Research on fungi isolated from freshwater environments contribute to expanding the fungal diversity and species inventory of freshwater ecosystems, as well as aiding in understanding the roles they play within these ecosystems. This study presents detailed descriptions and phylogenetic tree of 10 fungal species isolated from various freshwater environments in South Korea. These species were isolated from freshwater environments, such as plantlitter, sediment, and filtered freshwater. Identification of based on morphological characteristics and phylogenetic analysis using the DNA sequences from the internal transcribed spacer (ITS), elongation factor (EF1), calmodulin (cmd), β-tubulin (btub), and RNA polymerase II (rpb2) coding genes, depending on the species. The following species were recorded for the first time in Korea: Plectosphaerella pauciseptata NNIBRFG186, Striatibotrys rhabdosporus NNIBRFG2094, Gibellulopsis serrae NNIBRFG1912, Trichoderma hunanense NNIBRFG33378, T. Albofulvopsis NNIBRFG34098, Curvularia americana NNIBRFG34293, Phacidium mollerianum NNIBRFG28409, Mucor brunneogriseus NNIBRFG50199, M. laxorrhizus NNIBRFG37671, and M. pseudolusitanicus NNIBRFG39976.

The order Hypocreales, which belongs to the Ascomycota class Sordariomycetes, has a large number of species and occupies a variety of ecological niches, including saprophytic, symbiotic, and parasitic fungi. While much research has focused on terrestrial Hypocrealean fungi, there remains a significant gap in our understanding of their diversity and ecological roles in marine environments. In this study, we isolated 47 fungal strains from various marine habitats in South Korea. Through the polyphasic study, including phylogenetic analysis using multi-genetic markers (ITS, LSU, TEF1, RPB2, TUB, and ACT) and morphological analysis, we identified 21 species previously undiscovered in Korea, including 5 new and 16 unrecorded species. Our findings illustrate the species diversity of marine Hypocreales, highlighting the need for additional research into their ecological functions and potential in biotechnology and medicine.

Helvella, commonly known as saddle fungi, is a genus in the Helvellaceae family and is distributed globally. Recent comprehensive studies on Helvella have revealed that some Helvella species exhibit endemic traits and that many morphologically similar, cryptic species are phylogenetically distant. In this study, 202 Korean Helvella specimens collected between 1986 and 2023 were reevaluated through morphological analysis and phylogenetic characterization using barcode sequences, including nrLSU (nuclear Large Subunit Ribosomal DNA), hsp90 (Heat Shock Protein 90), and ITS (Internal Transcribed Spacer). The investigation confirmed the presence of at least 35 phylogenetic species in Korea. Among these, eight species (H. atroides, H. fistulosa, H. liquii, H. lobata, H. rugosa, H. subglabroides, H. sublactea, H. varia) were identified as previously unrecorded species in Korea, and seven new species (H. densipila, H. flavopus, H. macrospora, H. griseobrunnea, H. pseudolobata, H. parviflava, H. suborentitomentosa) were discovered. Of the 13 previously recorded Korean Helvella species, only three (H. ephippioides, H. macropus, H. orienticripsa) were confirmed, while the remaining ten species (H. acetabulum, H. atra, H. compressa, H. costifera, H. crispa, H. elastica, H. sublicia, H. fibrosa, H. lacunosa, H. pezizoides) were not detected in the samples studied. This study enhances our understanding of the distribution of Helvella species of Korea, revealing significant discrepancies between historical records and current findings. The discovery of new species and previously un-recorded species underscores the importance of continuous monitoring and reevaluation of fungal biodiversity.

The fungal strain KNUF-24-9L1a, belonging to the genus Phaeoacremonium, was isolated from gall-midge (Lasioptera sp.; Diptera: Cecidomyiidae) larvae and their galleries on a Chinese magnolia-vine (Schisandra chinensis) sample collected in Mungyeong-si, Gyeongbuk province, Korea. Phylogenetic analyses based on concatenated nucleotide sequences of the beta-tubulin and actin genes revealed that the strain clustered with Phaeoacremonium species but occupied a distinct phylogenetic position. Morphological differences between strain KNUF-24-9L1a and closely related species were also observed. In this study, we provide detailed descriptions, illustrations, and discussions of the morphological and phylogenetic analyses of closely related species to support the novelty of this isolated species. The phylogenetic and morphological evidence suggests that strain KNUF-24-9L1a represents a novel species within the genus Phaeoacremonium, which we have designated this species as Phaeoacremonium schisandrae sp. nov.

Edible mushroom cultivation often involves sterilizing the substrate, or a similar heat process like pasteurization, to facilitate mycelial colonization. Chemical treatments are an alternative approach that is also employed in some regions. Mycelial growth and density were analyzed in vitro by capturing daily photographs using a digital camera, with sterilized substrate serving as the control treatment. Our findings revealed that both fermented and sterilized substrates had similar growth patterns, although fermented treatment required a longer incubation time for full substrate colonization. Mycelium in fermented substrate had a denser structure compared to sterilized treatment, reflecting the interactions with the naturally-present microorganisms within the substrate. Conversely, mycelium in sterilized treatment exhibited faster substrate colonization times but had a less dense mycelial structure. Yeast and bacterial colonies were present throughout the fermentation process and 7 days after P. ostreatus mycelium inoculation, indicating active microbial communities during colonization. An initial decrease in CFU on the 3^rd day, followed by an increase by the 7^th day, suggests a shift toward anaerobic and facultative microorganisms due to oxygen depletion during fermentation. Mold colonies disappeared by the end of fermentation. Despite the complex interactions between yeast, bacteria, and P. ostreatus mycelium, the naturally-present microorganisms in the substrate appear to have at least neutral effects, enabling mycelial growth.

The plant pathogenic fungus Ascochyta rabiei produces solanapyrones, which are polyketide-derived secondary metabolites, during its saprobic growth on straws. Previously, we utilized A. rabiei as a heterologous host to produce a lichen-derived polyketide with anticancer activities. This study aimed to establish A. rabiei as a sustainable biorefinery for production of biologically active compounds through two objectives: optimizing culture conditions on agricultural waste substrates for polyketide production and generating a clean host using the Cre-loxP system for reusable antibiotic resistance markers. We found that soy hull is the most effective substrate among lignocellulosic materials. Neither light nor the addition of extra divalent cations were required for solanapyrone production in A. rabiei. Production of solanapyrones peaked 18 days after culture on soy hull pellets. To generate a clean host, we deleted the pks1 gene, involved in melanin biosynthesis, and the sol1 gene, responsible for solanapyrone production. Antibiotic resistance markers used in genetic transformation were recycled by establishing a Cre-loxP system in A. rabiei. In this system, Cre recombinase was expressed under the control of a promoter inducible during sporulation to mitigate the cytotoxicity of Cre. Here, we set the groundwork for developing A. rabiei as an environmentally-friendly biorefinery by generating a clean host with a Cre-loxP marker recycling system and optimizing growth conditions with soy hull pellets.

In this study, we aimed to analyze the annual, age- and sex-specific frequencies and antifungal resistance rates of Candida albicans infections over an 11-year period (2013 - 2023) at a university hospital in South Chungcheong Province, South Korea. A total of 476 cases identified as C. albicans from 260,769 blood cultures were analyzed retrospectively. The annual number of C. albicans isolates increased by 161.1% in 2019 and 136.7% in 2022 compared with that in the previous year. The mean age of patients from whom C. albicans was isolated was 65.8 years, with 51.8% patients being aged 60-79 years. The number of isolates was higher in male patients than in female patients (male-to-female ratio: 1.4:1). Of the isolates, 6.6% were resistant to flucytosine and 4.5% were resistant to voriconazole, whereas all isolates were susceptible to caspofungin and micafungin. Overall, this study provides vital foundational data for tertiary general hospitals in the Chungcheong region and for developing national infection management strategies, thereby providing a valuable basis for future in-depth studies.

The ability of Candida albicans to switch among yeast, hyphal, and pseudohyphal forms underlies its adaptability and pathogenicity. While cAMP-dependent signaling has long been considered central to hyphal growth, recent multi-omics studies show that cAMP-independent mechanisms also drive morphological changes. Basal PKA activity, cyclin-dependent kinases (e.g., Cdc28), and other regulators can promote shape-shifting even without classical cAMP pathways. In addition, N-acetylglucosamine (GlcNAc) acts as a potent signal that induces hyphal growth independently of its metabolic role, directly connecting environmental cues to morphological states. By integrating transcriptomic, proteomic, and phosphoproteomic data, this review exposes the intricate networks controlling C. albicans morphogenesis. A clearer understanding of these complex regulatory circuits lays the groundwork for future studies that employ advanced multi-omics analyses. Such approaches will help elucidate how these pathways converge, how they respond to changing environments, and how they might be harnessed or disrupted to influence fungal behavior.

This study was conducted to investigate the growth characteristics and morphology of Pleurotus ostreatus mycelium during co-cultivation with Pseudomonas putida. For selection of the most effective Pseudomonas species in coculture, Three strains of Pseudomonas putida and one strain of Pseudomonas fluorescens were co-cultured with heuktari, one of the varieties of P. ostreatus, on NPDA agar medium to observe the growth pattern of mycelium. It was found that the microorganism affecting mycelium growth during co-cultivation was P. putida KACC 10275, and co-cultivation of these two species resulted in enhanced mycelium growth on both NPDA and sawdust agar media. Furthermore, while primordium formation and fruit body development did not occur on plates inoculated only with heuktari, fruit bodies were observed only on plates where heuktari and P. putida were co-cultured, as confirmed by cultivation in the growth chamber for the same duration.