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Moringadepsin ( 6 ) and chaetone B ( 7 ) were isolated by us in the course of a conventional chemical screening of Morinagamyces vermicularis CBS 303.81, a fungus belonging to the relatively underexplored family Schizotheciaceae of the phylum Ascomycota. Since these metabolites did not account for the antifungal activity observed in a crude extract of this fungus, we utilized an MS/MS-based molecular networking approach to get a thorough insight into the secondary metabolites produced by this strain. Manual annotation of high-resolution fragmentation mass spectra by CANOPUS classified a major molecular family as putatively new thiodiketopiperazines. However, these results were opposite to the results of ChemWalker analysis based solely on MS/MS data, assigning these metabolites as various polyketides. Thus, targeted preparative HPLC isolation focusing on the most abundant features within this major molecular family resulted in the isolation of five secondary metabolites. Their structures were elucidated based on HRMS and NMR data as four new thiodiketopiperazine derivatives, botryosulfuranols D-G ( 1 - 4 ), alongside the known botryosulfuranol A ( 5 ). Compounds 1 - 3 and 5 exhibited moderate to weak antifungal activity against different test strains, accounting for the initial antifungal activity observed for its crude extract. Our study stressed the importance of full NMR-based structure elucidation for metabolomics research.

Background: The genus Microthecium contains 31 species worldwide distributed. Most of them are saprobic on soil and plant debris, but a few have been reported as mycoparasites on hypocrealean fungi. By contrast, this genus has never been reported as phytopathogenic, nor endophytic., Aims: To isolate and identify endophytic fungi from Mediterranean herbaceous plants and trees in order to contribute to the knowledge of the hosts and their geographical location. The present work has been focused on the study of endophytic fungi of hawthorn (Crataegus monogyna)., Methods: The following steps were taken: i, isolation of the fungal strain from living stems of C. monogyna; ii, cultural and micro-morphological study, and iii, sequence comparison of different genetic markers by BLAST search with sequences deposited in GenBank., Results: At the present work we describe a new species of the genus, Microthecium pleomorphosporum, isolated from living stems of C. monogyna in Mallorca (Balearic Islands, Spain). This fungus is characterized by the production of non-ostiolate perithecia and two sorts of ascospores (some smooth-walled, others delicately reticulated) bearing a germ pore at each end which are frequently ornamented by a surrounding donut-like structures, and a phialidic asexual morph and bulbils. The morphologically closest related species is Microthecium tenuissimum, which has bigger ascospores and lacks asexual reproduction. Phylogenetically, M pleomorphosporum is close-related to other species of the genus, although no genetic marker that discriminates this new species from other phylogenetically closer ones could be elucidated as a gold standard., Conclusions: M. pleomorphosporum, order Melanosporales, is reported here as the first endophytic species of C. monogyna., (Copyright © 2023 The Author(s). Publicado por Elsevier España, S.L.U. All rights reserved.)

Human infections by pleosporalean fungi (class Dothideomycetes, phylum Ascomycota) are rarely reported. Because their identification is challenging using morphological characterization, several phylogenetic markers must be sequenced for an accurate identification and taxonomical placement of the isolates. Three isolates of clinical origin were phenotypically characterized, but due to the absence of relevant morphological traits, D1-D2 domains of the 28S nrRNA gene (LSU), the internal transcribed spacer region (ITS) of the nrRNA, and fragments of the RNA polymerase II subunit 2 (rpb2) and translation elongation factor 1-alpha (tef1) genes were sequenced to allow a phylogenetic analysis that would solve their phylogenetic placement. That analysis revealed that these isolates did not match any previously known pleosporalean genera, and they are proposed here as the new fungal genus, Gambiomyces. Unfortunately, the isolates remained sterile, which, consequently, made the morphological description of the reproductive structures impossible. Future studies should try to understand the behaviour of this fungus in nature as well as its characteristics as an opportunistic fungal pathogen. Molecular identification is becoming an essential tool for proper identification of Dothideomycetes of clinical origin., Lay Abstract: We describe a new pleosporalen pathogenic fungus, Gambiomyces profunda, found in superficial to deep samples from a human patient. Because all strains remained sterile, the fungus was finally identified following a phylogenetic analysis by using four different molecular markers., (© The Author(s) 2020. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Following the discovery of a new class of compounds that inhibit the mucosa-associated lymphoid tissue lymphoma translocation 1 (MALT1) protease in a prior study, further chemical investigation of the Dictyosporium digitatum fungus resulted in the identification of 16 additional metabolites, including 12 undescribed compounds (1-12). The constitution and relative configuration of these new molecules were established by comprehensive NMR and HRMS analyses. Their absolute configurations were determined by employing Mosher's ester analysis and TDDFT ECD calculations. Two sesquiterpenes, dictyosporins A (1) and B (2), possess an undescribed eudesmen-type of structural scaffold. The ability of the isolated compounds to inhibit MALT1 proteolytic activity was evaluated, but none of them exhibited significant inhibition., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Published by Elsevier Ltd.)

Background: The coelomycetes comprise a wide range of fungal species distributed in at least three different classes of the phylum Ascomycota. These are morphologically characterised by producing their conidia inside of fruiting bodies called pycnidia or acervuli, and only a reduced number of species are able to cause human infections. However, their identification in the clinical laboratory is often difficult, due to their few morphological features or because they remain sterile., Materials and Methods: In the present study, three isolates of coelomycetes of clinical origin were phenotypically and molecularly studied, by sequencing the D1-D2 fragment of the 28S nuclear ribosomal RNA (nrRNA) (LSU), the internal transcribed spacer region (ITS1-5.8S-ITS2) and a fragment of the translation elongation factor 1-alpha (tef1) genes., Results and Conclusions: As result of the molecular analysis, the isolates were identified as belonging to the genus Gloniopsis (order Hysteriales, Dothideomycetes) but without the characteristics of any of the species described so far. Therefore, we propose the new species Gloniopsis percutanea and Gloniopsis pneumoniae. Furthermore, this study revealed that some isolates from clinical specimens identified previously as Rhytidhysteron spp. were misidentified, and considering the few studies in the order Hysteriales and the scarce number of sequences of phylogenetic markers, future revisions of this order should be performed to clarify their taxonomy and obtain a better identification from isolates involved in human mycoses., (© 2019 Blackwell Verlag GmbH.)

Although there have been few reports of opportunistic infections (superficial and systemic) caused by coelomycetous fungi, they are becoming more frequent. Neocucurbitaria keratinophila (formerly Pyrenochaeta keratinophila), characterized by producing pycnidial conidiomata and small hyaline conidia, seems to be an emergent opportunistic pathogen in Spain. Since this fungus was first reported from human keratitis, eight strains have been isolates from clinical cases in Spain. This is a retrospective study of these fungal strains, including phenotypic and molecular characterizations, and in vitro antifungal susceptibility assays. These clinical strains were identified by sequencing four phylogenetic markers such as the internal transcribed spacer region (ITS1-5.8S-ITS2) and fragments of the 28S nrRNA (LSU), beta-tubulin (tub2), and RNA polymerase II subunit 2 (rpb2) genes, and by morphological characterization. All the strains tested were susceptible to the majority of antifungals, being isavuconazole the only drug that showed a poor antifungal activity., (© The Author(s) 2018. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

The taxonomy of the fungi that produce human infections and that develop asexual fruiting bodies in culture has become very complex. Recent molecular studies have produced dramatic changes in their classification. Currently, the coelomycetes traditionally included in Sphaeropsidales and Melanconiales are in fact distributed across at least three different classes of the Phylum Ascomycota. Approximately 1000 genera and 7000 species have been grouped in the classes Dothideomycetes, Leotiomycetes and Sordariomycetes and their proper identification can only be made by analysing their DNA sequences and comparing them with those corresponding to type strains available in the adequate databases. To facilitate this task for scientists and clinicians involved in the study of these complex, and every day more numerous taxa, we have updated the knowledge about the taxonomy of the commonest coelomycetes of clinical interest with the aim of improving their identification and antifungal treatment., (© 2018 Blackwell Verlag GmbH.)

Human infections by coelomycetous fungi are becoming more frequent and range from superficial to systemic dissemination. Traumatic implantation of contaminated plant material is the most common cause. The typical morphological feature of these fungi is the production of asexual spores (conidia) within fruiting bodies called conidiomata. This study aimed to determine the distribution of the coelomycetes in clinical samples by a phenotypic and molecular study of a large set of isolates received from a U.S. reference mycological institution and by obtaining the in vitro antifungal susceptibility pattern of nine antifungals against a selected group of isolates. A total of 230 isolates were identified by sequencing the D1 and D2 domains of the large subunit (LSU) nuclear ribosomal RNA (nrRNA) gene and by morphological characterization. Eleven orders of the phylum Ascomycota were identified: Pleosporales (the largest group; 66.1%), Botryosphaeriales (19.57%), Glomerellales (4.35%), Diaporthales (3.48%), Xylariales (2.17%), Hysteriales and Valsariales (0.87%), and Capnodiales, Helotiales, Hypocreales and Magnaporthales (0.43% each). The most prevalent species were Neoscytalidium dimidiatum, Paraconiothyrium spp., Phoma herbarum, Didymella heteroderae, and Epicoccum sorghinum The most common anatomical site of isolation was superficial tissue (66.5%), followed by the respiratory tract (17.4%). Most of the isolates tested were susceptible to the majority of antifungals, and only flucytosine showed poor antifungal activity., (Copyright © 2017 American Society for Microbiology.)

Based on a number of isolates of Myceliophthora (Chaetomiaceae, Sordariales, Ascomycota) recently isolated from soil samples collected in USA, the taxonomy of the genus was re-evaluated through phylogenetic analyses of sequences from the nuc rDNA internal transcribed spacer region and genes for the second largest subunit of RNA polymerase II and translation elongation factor 1α. Members of Myceliophthora were split into four monophyletic clades strongly supported by molecular and phenotypic data. Such clades correspond with Myceliophthora, now restricted only to the type species of the genus Corynascus, which is re-established with five species, the new monotypic genus Crassicarpon and also the new genus Thermothelomyces (comprising four species). Myceliophthora lutea is mesophilic and a permanently asexual morph compared to the members of the other three mentioned genera, which also are able to sexually reproduce morphs with experimentally proven links to their asexual morphs. The asexual morph of M. lutea is characterized by broadly ellipsoidal, smooth-walled conidia with a wide, truncate base. Crassicarpon thermophilum is thermophilic and heterothallic and produces spherical to cuneiform, smooth-walled conidia and cleistothecial ascomata of smooth-walled, angular cells and ascospores with a germ pore at each end. Corynascus spp. are homothallic and mesophilic and produce spherical, mostly ornamented conidia and cleistothecial ascomata with textura epidermoidea composed of ornamented wall cells, and ascospores with one germ pore at each end. Thermothelomyces spp. are thermophilic, heterothallic and characterized by similar ascomata and conidia as Corynascus spp., but its ascospores exhibit only a single germ pore. A dichotomous key to distinguish Myceliophthora from the other mentioned genera are provided, as well as dichotomous keys to identify the species of Corynascus and Thermothelomyces. A new species, namely Corynascus fumimontanus, characterized by verrucose ascomatal wall cells and irregularly shaped ascospores, is described and illustrated., (© 2015 by The Mycological Society of America.)

The genus Spiromastix consists of several fungal species that have been isolated from soil and animal dung in various parts of the world. However, these species are considered to be of low pathogenic potential, as no cases of infections caused by these fungi have been reported. Here, we describe the clinical course of discospondylitis in a dog from which a fungus was cultured from a biopsy and identified as a Spiromastix species by morphologic characteristics and sequencing. Phylogenetic analysis determined this to be a new species, Spiromastix asexualis, which is described, and a new order, Spiromastixales, is proposed., (© 2014 Blackwell Verlag GmbH.)

The morphology of sexual fruit bodies has been historically regarded as a key character in fungal taxonomy. In the 1970s the class Plectomycetes was recognized in order to classify the cleistothecial ascomycetes. However, recent analysis of DNA sequencing data concerning the phylogeny of numerous cleistothecial ascomycetes confirmed that the criterion of the production of closed ascomata without a predefined opening and with an irregular arrangement of the asci at the centrum is of little systematic value, as pointed out by different authors on the basis of morphological studies.

Although the taxonomy of ascomycetes has changed dramatically, generic delimitation within the recently proposed order Coniochaetales has not been resolved. In order to clarify the phylogenetic relationships of genera in the Coniochaetaceae, we performed a molecular study based on the analyses of the sequences of the partial SSU and of the variable domains of the LSU rDNA genes. The phylogenetic trees obtained do not support the monophyly of the genera Coniochaeta, Coniochaetidium, Ephemeroascus, and Poroconiochaeta. A morphological study confirmed that there were not enough differences to distinguish these genera, and the latter three are treated as synonyms of Coniochaeta. The phialidic anamorph proved to be an informative phylogenetic character in Coniochaetales, while that the type of ascomata (cleistothecial or perithecial) and the ornamentation of the ascospore walls were of little taxonomic value at the generic level. The circumscription of the genus Coniochaeta is revised. The genera Coniocessia and Coniolariella are proposed as new within the order Xylariales to accommodate Coniochaeta nodulisporioides, and C. gamsii, respectively. The taxonomic position of Synaptospora and Wallrothiella subiculosa are also discussed.

Two new ascomycetes, Boerlagiomyces costaricensis (Pleosporales) and Scopinella musciformis (Sordariales sensu lato), from litter samples collected in rainforests of Costa Rica, are described and illustrated. Boerlagiomyces costaricensis has globose, ostiolate ascomata covered by numerous setae-like hairs; cylindrical, fissitunicate asci without apical structures; and large, fusiform, muriform, hyaline to pale brown ascospores. Scopinella musciformis is characterized by ostiolate ascomata with a few compact clusters of hypha-like hairs distributed on the peridial surface and a long neck; ovate to ellipsoidal unitunicate asci; and small quadrangular ascospores with diagonal germ slits.