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Purpose: Rare yeasts species are increasingly reported as causative agents of invasive human infection. Proper identification and antifungal therapy are essential to manage these infections. Candida blankii is one of these emerging pathogens and is known for its reduced susceptibility to multiple antifungals., Methods: To obtain more insight into the characteristics of this species, 26 isolates reported as C. blankii were investigated using genetic and phenotypical approaches., Results: Among the 26 isolates, seven recovered either from blood, sputum, urine, or the oral cavity, displayed substantial genetic and some phenotypical differences compared to the other isolates, which were confirmed as C. blankii. We consider these seven strains to represent a novel species, Tardiomyces depauwii. Phylogenomics assigned C. blankii, C. digboiensis, and the novel species in a distinct branch within the order Dipodascales, for which the novel genus Tardiomyces is erected. The new combinations Tardiomyces blankii and Tardiomyces digboiensis are introduced. Differences with related, strictly environmental genera Sugiyamaella, Crinitomyces, and Diddensiella are enumerated. All three Tardiomyces species share the rare ability to grow up to 42 °C, display slower growth in nutrient-poor media, and show a reduced susceptibility to azoles and echinocandins. Characteristics of T. depauwii include high MIC values with voriconazole and a unique protein pattern., Conclusion: We propose the novel yeast species Tardiomyces depauwii and the transfer of C. blankii and C. digboiensis to the novel Tardiomyces genus., (© 2024. The Author(s).)

In eukaryotes, phosphorylation of the α-subunit of eIF2 is a mechanism to adjust cellular gene expression profiles in response to specific signals. The eIF2α kinases are a group of serine-threonine kinases that perform important functions in response to infection, proteotoxicity, and nutrient scavenging. The conserved nature of eIF2α kinases among fungi makes them potential evolutionary markers, which may contribute to deeper understanding of taxonomy and evolution. To date, only few studies are available of eIF2α kinases in black yeasts, which are members of Chaetothyriales containing potential agents of a gamut of major human diseases, such as chromoblastomycosis, phaeohyphomycosis and mycetoma. To establish the phylogenetic validity of sequences of eIF2α kinases hypothetical genes, we compared these genes between members of different classes of fungi, including black yeasts and allies, aiming at evaluation of the phylogeny of this group using an alternative molecular marker, compared to standard ribosomal genes. Trees generated with eIF2α kinase sequences of fungi were compared with those generated by ribosomal internal transcribed spacers (ITS rDNA) sequences from the same species. Sequences used were obtained from the protein Non-redundant database of NCBI, were aligned using CLUSTALX v1.8 and alignments were analyzed with RAxML v8.2.9 on the CIPRES Science Gateway portal. The trees generated had similar topologies, demonstrating that eIF2α kinases hypothetical gene sequences present a coherent reflection of evolution among fungi, compared to trees reconstructed by the use of ribosomal sequences. Our preliminary findings with a limited dataset strongly suggest that the evolution of kinases among black yeasts follows a similar path as revealed by ribosomal data, which underlines the validity of current taxonomy of black yeasts and relatives., Competing Interests: Declaration of competing interest The authors have no conflicts of interest to declare and confirm that each one has made substantial contributions to the information or materials submitted for publication., (Copyright © 2020 British Mycological Society. Published by Elsevier Ltd. All rights reserved.)

Mycetoma, a chronic and mutilating subcutaneous infection recognized by the WHO as a neglected tropical disease, has been reported in >25 countries in Africa, Asia, and South America. In Latin America, Trematosphaeria grisea is assumed to be the prevalent fungal agent. Recent molecular studies have shown that this is an environmental saprobe in Europe, where it is rarely implicated in human diseases. The aim of the present paper is to establish the identity of Latin American cases ascribed to Trematosphaeria grisea Three cases analyzed were caused by Nigrograna mackinnonii Data on an additional 21 strains in the literature revealed that N. mackinnonii rather than T. grisea is responsible for most cases of black grain eumycetoma in Latin America., (Copyright © 2018 American Society for Microbiology.)

A novel dimorphic fungus, Emergomyces orientalis sp. nov. a close relative of systemic pathogens in the family Ajellomycetaceae (Blastomyces, Histoplasma). The fungus is reported in a 64-year-old male from Shanxi, China. The patient developed disseminated skin lesions, productive cough with fever and showed nodular opacities in his left lung on chest radiography. The patient had no identified cause of immunodeficiency apart from type-2 diabetes mellitus. Clinical, histopathological and mycological characteristics of the agent are given, and its phylogenetic position is determined with multilocus sequence data., (© 2017 The Authors. Mycoses Published by Blackwell Verlag GmbH.)

The frequency and the geographical extent of symbiotic associations between ants and fungi of the order Chaetothyriales have been highlighted only recently. Using a phylogenetic approach based on seven molecular markers, we showed that ant-associated Chaetothyriales are scattered through the phylogeny of this order. There was no clustering according to geographical origin or to the taxonomy of the ant host. However, strains tended to be clustered according to the type of association with ants: strains from ant-made carton and strains from plant cavities occupied by ants ('domatia') rarely clustered together. Defining molecular operational taxonomic units (MOTUs) with an internal transcribed spacer sequence similarity cut-off of 99% revealed that a single MOTU could be composed of strains collected from various ant species and from several continents. Some ant-associated MOTUs also contained strains isolated from habitats other than ant-associated structures. Altogether, our results suggest that the degree of specialization of the interactions between ants and their fungal partners is highly variable. A better knowledge of the ecology of these interactions and a more comprehensive sampling of the fungal order are needed to elucidate the evolutionary history of mutualistic symbioses between ants and Chaetothyriales., (© 2017 The Author(s).)

The genus Fonsecaea comprises black yeast-like fungi of clinical relevance, including etiologic agents of chromoblastomycosis and cerebral phaeohyphomycosis. Presence of melanin and assimilation of monoaromatic hydrocarbons and alkylbenzenes have been proposed as virulence factors. Multicopper oxidase (MCO) is a family of enzymes including laccases, ferroxidases and ascorbate oxidases which are able to catalyze the oxidation of various aromatic organic compounds with the reduction of molecular oxygen to water. Additionally, laccases are required for the production of fungal melanins, a cell-wall black pigment recognized as a key polymer for pathogenicity and extremotolerance in black yeast-like fungi. Although the activity of laccase enzymes has previously been reported in many wood-rotting fungi, the diversity of laccase genes in Fonsecaea has not yet been assessed. In this study, we identified and characterized laccase-coding genes and determined their genomic location in five clinical and environmental Fonsecaea species. The identification of laccases sensu stricto will provide insights into carbon acquisition strategies as well as melanin production in Fonsecaea., Competing Interests: The authors have declared that no competing interests exist.

Acremonium is one of the largest and most complex genera of hyphomycetes. Its taxonomy is not yet resolved and the phylogenetic value of the most distinctive morphological features is unknown. The species of this genus produce conidia in chains or form slimy heads or both. We have studied a set of clinical and environmental Acremonium strains morphologically characterized by producing mostly catenate, elongate, more or less fusiform conidia. Based on phenotypic data and in the analysis of the sequences of the ITS region, the D1/D2 domains of the 28S rRNA gene and a fragment of the β-tubulin gene, three new species morphologically similar to Acremonium fusidioides and belonging to the family Bionectriaceae (Hypocreales) are described and illustrated; they are Acremonium pilosum, Acremonium parvum and Acremonium citrinum. The first species produces two kinds of conidia: clavate with smooth walls and globose with abundant filiform projections. Acremonium parvum is characterized by slow growth and pyriform or slightly lanceolate conidia with an elongate and truncate base. Acremonium citrinum produces a diffusible yellow pigment and obovoid conidia.

In a survey on the diversity of microfungi in Spanish soils, two new species of Acremonium were found. Both species were characterized as having more or less erect, mostly branched conidiophores bearing whorls of acicular phialides. In addition, one of these species, Acremonium asperulatum, produced abundant chlamydospores and globose rough-walled conidia. The other species, Acremonium variecolor, produced a brownish diffusible pigment and smooth-walled, subglobose conidia with apiculate base; sessile conidia inserted directly on vegetative hyphae also were present. The analysis of the sequences of the ITS region, the D1/D2 domains of the 28S rRNA gene and a fragment of the actin gene revealed relationships of both species with members of the Bionectriaceae (Hypocreales). Genetic differences were observed with morphologically similar species.