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Fungi in the basidiomycete genusMalasseziaare the most prevalent eukaryotic microbes resident on the skin of human and other warm-blooded animals and have been implicated in skin diseases and systemic disorders. Analysis ofMalasseziagenomes revealed that key adaptations to the skin microenvironment have a direct genomic basis, and the identification of mating and meiotic genes suggests a capacity to reproduce sexually, even though no sexual cycle has been as yet observed. In contrast to other bipolar or tetrapolar basidiomycetes that have either two linked mating-type-determining (MAT) loci or twoMATloci on separate chromosomes, inMalasseziaspecies studied thus far the twoMATloci are arranged in a pseudobipolar configuration (linked on the same chromosome but capable of recombining). By incorporating newly-generated chromosome-level genome assemblies, and an improvedMalasseziaphylogeny, we infer that the pseudobipolar arrangement was the ancestral state of this group and revealed six independent transitions to tetrapolarity, seemingly driven by centromere fission or translocations in centromere-flanking regions. Additionally, in an approach to uncover a sexual cycle,Malassezia furfurstrains were engineered to express differentMATalleles in the same cell. The resulting strains produce hyphae reminiscent of early steps in sexual development and display upregulation of genes associated with sexual development as well as others encoding lipases and a protease potentially relevant for pathogenesis of the fungus. Our study reveals a previously unseen genomic relocation of mating-type loci in fungi and provides insight towards the discovery of a sexual cycle inMalassezia, with possible implications for pathogenicity.Significance StatementMalassezia, the dominant fungal group of the mammalian skin microbiome, is associated with numerous skin disorders. Sexual development and yeast-to-hyphae transitions, governed by genes at two mating-type (MAT) loci, are thought to be important for fungal pathogenicity. However,Malasseziasexual reproduction has never been observed. Here, we employed chromosome-level assemblies and comparative genomics to uncover unforeseen transitions inMATloci organization withinMalassezia, possibly related with fragility of centromeric-associated regions. Additionally, by expressing differentMATalleles in the same cell, we show thatMalasseziacan undergo hyphal development and this phenotype is associated with increased expression of key mating genes along with other genes known to be virulence factors, providing a possible connection between hyphal development, sexual reproduction, and pathogenicity.

The genusMalasseziais an opportunistic lipid-dependent yeast that is associated with common skin diseases and has recently been associated with Crohn’s disease and certain cancers. Understanding the susceptibility ofMalasseziato diverse antimicrobial agents is crucial for identifying effective antifungal therapies. Here, we tested the efficacy of isavuconazole, itraconazole, terbinafine and artemisinin against threeMalasseziaspecies:M. restricta, M. slooffiae, andM. sympodialis, using microbroth dilution techniques. We found antifungal properties for the two previously-unstudied antimicrobials: isavuconazole and artemisinin. Overall allMalasseziaspecies were particularly susceptible to itraconazole, with a MIC range from 0.0015 to 0.1562 μM.ImportanceTheMalasseziagenus is known to be a cause of skin conditions and has recently been associated with diseases such as Crohn’s disease, pancreatic ductal carcinoma and breast cancer. This work was completed to assess the susceptibility to a variety of antimicrobial drugs on diverseMalasseziaspecies, in particularMalassezia restricta.

The non-pathogenic TH17 subset of helper T cells clears fungal infections, whereas pathogenic TH17 cells cause inflammation and tissue damage; however, the mechanisms controlling these distinct responses remain unclear. Here we found that fungi sensing by the C-type lectin dectin-1 in human dendritic cells (DCs) directed the polarization of non-pathogenic TH17 cells. Dectin-1 signaling triggered transient and intermediate expression of interferon (IFN)-β in DCs, which was mediated by the opposed activities of transcription factors IRF1 and IRF5. IFN-β-induced signaling led to integrin αvβ8 expression directly and to the release of the active form of the cytokine transforming growth factor (TGF)-β indirectly. Uncontrolled IFN-β responses as a result of IRF1 deficiency induced high expression of the IFN-stimulated gene BST2 in DCs and restrained TGF-β activation. Active TGF-β was required for polarization of non-pathogenic TH17 cells, whereas pathogenic TH17 cells developed in the absence of active TGF-β. Thus, dectin-1-mediated modulation of type I IFN responses allowed TGF-β activation and non-pathogenic TH17 cell development during fungal infections in humans.

A new species of the yeast genus Blastobotrys was discovered during a worldwide survey of culturable xerophilic fungi in house dust. Several culture-dependent and independent studies from around the world detected the same species from a wide range of substrates including indoor air, cave wall paintings, bats, mummies, and the iconic self-portrait of Leonardo da Vinci from ca 1512. However, none of these studies identified their strains, clones, or OTUs as Blastobotrys. We introduce the new species as Blastobotrys davincii f.a., sp. nov. (holotype CBS H-24879) and delineate it from other species using morphological, phylogenetic, and physiological characters. The new species of asexually (anamorphic) budding yeast is classified in Trichomonascaceae and forms a clade along with its associated sexual state genus Trichomonascus. Despite the decade-old requirement to use a single generic name for fungi, both names are still used. Selection of the preferred name awaits a formal nomenclatural proposal. We present arguments for adopting Blastobotrys over Trichomonascus and introduce four new combinations as Blastobotrys allociferrii (≡ Candida allociferrii), B. fungorum (≡ Sporothrix fungorum), B. mucifer (≡ Candida mucifera), and Blastobotrys vanleenenianus (≡ Trichomonascus vanleenenianus). We provide a nomenclatural review and an accepted species list for the 37 accepted species in the Blastobotrys/Trichomonascus clade. Finally, we discuss the identity of the DNA clones detected on the da Vinci portrait, and the importance of using appropriate media to isolate xerophilic or halophilic fungi.

S1.3 Malassezia: genetics, genomics, and biology, September 21, 2022, 11:00 AM - 12:30 PM The Basidiomycetous yeast Malassezia is the most abundant fungal genus on healthy human skin but may also cause various skin disorders such as seborrheic dermatitis, dandruff, and pityriasis versicolor. In recent years, Malassezia has increasingly been implicated in health and disease beyond the skin: as an underestimated cause of Malassezia bloodstream infections (BSIs) in immunocompromised patients and neonates, associated with Crohn's disease, promoting pancreatic oncogenesis, and exacerbating cystic fibrosis. Malassezia furfur is the number one Malassezia BSI cause and is also implicated in many skin disorders. With these new discoveries of Malassezia’s impact on human health, the need for a better understanding of its evolution and pathobiology also became more pressing. Hybridization has been suggested as a biological mechanism of adaptation to new hosts, and may lead to increased pathogenicity. Many examples of major hybrid yeast pathogens exist, such as Candida albicans, C. orthopsilosis, C. metapsilosis, and multiple examples in the Cryptococcus gattii/Cryptococcus neoformans species complex. Here the multiple hybridization events of the Malassezia furfur species complex will be discussed. Two distinct hybridization events occurred between the same parental lineages, and these parental strains were originally also hybrids. The identification of a pseudobipolar mating system and the analysis of the mating-type loci provide evidence that sexual liaisons of mating compatible cells from these parental lineages led to a diploid/aneuploid state in the hybrid lineages. Sequence similarity percentages suggest that both parental lineages in fact are two different species. The genetic diversity of ca 300 strains belonging to this species complex is evaluated in relationship to host background and phenotype.

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM Objectives We describe a fatal case of trichosporonosis caused by Trichosporon asahii. The aim was to molecularly characterize the T. asahii strains from blood and foot tissue samples to investigate their genetic relatedness. Case An 85-year-old morbidly obese female with a prior cerebrovascular accident, hypertension, and diabetes mellitus was admitted to a peripheral hospital with type II respiratory failure, metabolic acidosis, and chronic anemia. Three weeks post-hospitalization the patient remained febrile, physical examination showed that the patient had paronychia, nail pigmentation, subungual onychomycosis, and a diabetic foot ulcer. Blood culture, as well as nail and ulcer samples, became positive for Trichosporon yeasts. Methods Trichosporon yeasts were subjected to molecular identification by sequencing the intergenic spacer (IGS1) region. Minimal inhibitory concentrations (MICs) were determined by the EUCAST microdilution method. Long-read nanopore sequencing was performed for the three clinical strains, the type-strain of T. asahii (CBS2479), and two IGS-genotype 7 strains (CBS2936, CBS7632) using the native barcoding kit v12 (SQK-LSK112; Oxford Nanopore Technologies). Raw data were basecalled with Guppy v6, Flye v2.9 was used to de novo assemble the genome of CBS2479, this was used as a reference for variant calling using the genomic reads of all strains. Results The three clinical strains were found to belong to the rare IGS-genotype 7 and had similar MICs for amphotericin B (4 µg/ml), 5-fluorocytosine and fluconazole (2 µg/ml), voriconazole (≤ 0.015 µg/ml), posaconazole (0.0625 µg/ml), itraconazole (0.125 µg/ml), caspofungin (8 µg/ml), anidulafungin and micafungin (> 16 µg/ml). Strains from the ulcer and nail were genetically very closely related with 10 836 SNPs differences, the blood-derived strain differed more from these two strains with 94 729 SNPs and 94 913 SNPs, respectively. Strains CBS2936 and CBS7632 were only distantly related to CBS2479 with 328 221, and 436 060 SNPs, respectively. Conclusion The T. Asahii IGS-genotype 7 strain causing fatal fungemia was genetically nearly identical to that obtained from nail and foot ulcers, making it highly likely that this was the port d'entrée for T. asahii.

Species delimitation is one of the most fundamental processes in biology. Biodiversity undertakings, for instance, require explicit species concepts and criteria for species delimitation in order to be relevant and translatable. However, a perfect species concept does not exist for Fungi. Here, we review the species concepts commonly used in Basidiomycota, the second largest phylum of Fungi that contains some of the best known species of mushrooms, rusts, smuts, and jelly fungi. In general, best practice is to delimitate species, publish new taxa, and conduct taxonomic revisions based on as many independent lines of evidence as possible, that is, by applying a so-called unifying (or integrative) conceptual framework. However, the types of data used vary considerably from group to group. For this reason we discuss the different classes of Basidiomycota, and for each provide: (i) a general introduction with difficulties faced in species recognition, (ii) species concepts and methods for species delimitation, and (iii) community recommendations and conclusions.

Malassezia species are important fungal skin commensals and are part of the normal microbiota of humans and other animals. However, under certain circumstances these fungi can also display a pathogenic behaviour. For example, Malassezia furfur is a common commensal of human skin, and yet is often responsible for skin disorders but also systemic infections. Comparative genomics analysis of M. furfur revealed that some isolates have a hybrid origin, similar to several other recently described hybrid fungal pathogens. Because hybrid species exhibit genomic plasticity that can impact phenotypes, we sought to elucidate the genomic evolution and phenotypic characteristics of M. furfur hybrids in comparison to their parental lineages. To this end, we performed a comparative genomics analysis between hybrid strains and their presumptive parental lineages, and assessed phenotypic characteristics. Our results provide evidence that at least two distinct hybridization events occurred between the same parental lineages, and that the parental strains may have originally been hybrids themselves. Analysis of the mating-type locus reveals that M. furfur has a pseudobipolar mating system, and provides evidence that after sexual liaisons of mating compatible cells, hybridization involved cell-cell fusion leading to a diploid/aneuploid state. This study provides new insights into the evolutionary trajectory of M. furfur and contributes with valuable genomic resources for future pathogenicity studies.ImportanceMalassezia furfur is a common commensal member of human/animal microbiota that is also associated with several pathogenic states. Recent studies report involvement of Malassezia species in Crohn’s disease, a type of inflammatory bowel disease, pancreatic cancer progression, and exacerbation of Cystic fibrosis. A recent genomics analysis of M. furfur revealed the existence of hybrid isolates and identified their putative parental lineages. In this study, we explored the genomic and phenotypic features of these hybrids in comparison to their putative parental lineages. Our results revealed the existence of a pseudobipolar mating system in this species and showed evidence for the occurrence of multiple hybridization events in the evolutionary trajectory of M. furfur. These findings significantly advance our understanding of the evolution of this commensal microbe and are relevant for future studies exploring the role of hybridization in the adaptation to new niches or environments, including the emergence of pathogenicity.

Malassezia furfur is a yeast species belonging to Malasseziomycetes, Ustilaginomycotina and Basidiomycota that is found on healthy warm-blooded animal skin, but also involved in various skin disorders like seborrheic dermatitis/dandruff and pityriasis versicolor. Moreover, Malassezia are associated with bloodstream infections, Crohn's disease and pancreatic carcinoma. Recent advances in Malassezia genomics and genetics have focused on the nuclear genome. In this work, we present the M. furfur mitochondrial (mt) genetic heterogenicity with full analysis of 14 novel and six available M. furfur mt genomes. The mitogenome analysis reveals a mt gene content typical for fungi, including identification of variable mt regions suitable for intra-species discrimination. Three of them, namely the trnK–atp6 and cox3–nad3 intergenic regions and intron 2 of the cob gene, were selected for primer design to identify strain differences. Malassezia furfur strains belonging to known genetic variable clusters, based on AFLP and nuclear loci, were assessed for their mt variation using PCR amplification and sequencing. The results suggest that these mt regions are excellent molecular markers for the typing of M. furfur strains and may provide added value to nuclear regions when assessing evolutionary relationships at the intraspecies level., A total of 20 M. furfur mt genomes show a highly conserved gene order but vary in intron abundance and intergenic regions, revealing promising multicopy target regions for typing.

Saccharomycotina yeasts contain diverse clades within the kingdom of Fungi and are important to human everyday life. This work investigates the evolutionary relationships among these yeasts from a mitochondrial (mt) genomic perspective. A comparative study of 141 yeast mt genomes representing all major phylogenetic lineages of Saccharomycotina was performed, including genome size and content variability, intron and intergenic regions’ diversity, genetic code alterations and syntenic variation. Findings from this study suggest that mt genome size diversity is the result of a ceaseless random process mainly based on genetic recombination and intron mobility. Gene order analysis revealed conserved syntenic units and many occurring rearrangements, which can be correlated with major evolutionary events as shown by the phylogenetic analysis of the concatenated mt protein matrix. For the first time, molecular dating indicated a slower mt genome divergence rate in the early stages of yeast evolution, in contrast with a faster rate in the late evolutionary stages, compared to their nuclear time divergence. Genetic code reassignments of mt genomes are a perpetual process happening in many different parallel evolutionary steps throughout Saccharomycotina evolution. Overall, this work shows that phylogenetic studies that employ the mt genome of yeasts highlight major evolutionary events.

The non-pathogenic T

Malassezia yeasts are commensal microorganisms occurring on the skin of humans and animals causing dermatological disorders or systemic infections in severely immunocompromised hosts. Despite attempts to control such yeast infections with topical and systemic antifungals, recurrence of clinical signs of skin infections as well as treatment failure in preventing or treating Malassezia furfur fungemia have been reported most likely due to wrong management of these infections (e.g., due to early termination of treatment) or due to the occurrence of resistant phenomena. Standardized methods for in vitro antifungal susceptibility tests of these yeasts are still lacking, thus resulting in variable susceptibility profiles to azoles among Malassezia spp. and a lack of clinical breakpoints. The inherent limitations to the current pharmacological treatments for Malassezia infections both in humans and animals, stimulated the interest of the scientific community to discover new, effective antifungal drugs or substances to treat these infections. In this review, data about the in vivo and in vitro antifungal activity of the most commonly employed drugs (i.e., azoles, polyenes, allylamines, and echinocandins) against Malassezia yeasts, with a focus on human bloodstream infections, are summarized and their clinical implications are discussed. In addition, the usefulness of alternative compounds is discussed.

During a study on the occurrence of lipid-dependent Malassezia spp. in domestic animals, some atypical strains, phylogenetically related to Malassezia sympodialis Simmons et Guého, were shown to represent novel species. In this study, we describe two new taxa, Malassezia caprae sp. nov. (type strain MA383=CBS 10434), isolated mainly from goats, and Malassezia equina sp. nov. (type strain MA146=CBS 9969), isolated mainly from horses, including their morphological and physiological characteristics. The validation of these new taxa is further supported by analysis of the D1/D2 regions of the 26S rRNA gene, the ITS1-5.8S-ITS2 rRNA, the RNA polymerase subunit 1 and chitin synthase nucleotide sequences, and the amplified fragment length polymorphism patterns, which were all consistent in separating these new species from the other species of the genus, and those of the M. sympodialis species cluster, specifically.

To address the challenges of efficiently performing continuous innovation with sustainable quality, Canon Production Printing envisions the exploitation of models during the complete lifecycle of printer variants. The design of professional digital printers involves several engineering disciplines ranging from software and electrical and mechanical hardware to physics and chemistry. All these engineering disciplines already exploit various models in diverse tools to support their design activities. Apart from exploiting commodity modeling tools that are used in domain-specific ways, specialized domain-specific modeling tools are also developed. At the time of writing, Canon Production Printing had selected JetBrains MPS as one of the core technologies to interconnect the diverse range of models at the specification level. Such models are, for example, used for configuring virtual printers for analysis (e.g., by means of simulation), generation of documentation, and automating synthesis in some engineering disciplines. To allow for automated processing, MPS is also used for capturing domain-specific knowledge in models that has not yet been formalized. At the time of writing, approximately 10 people at Canon Production Printing develop domain-specific languages using MPS and approximately 40 people use these as part of their daily printer development activities. This chapter gives an overview of some of the applications of MPS at Canon Production Printing and how it is changing the way-of-working to achieve efficient continuous innovation with sustainable quality.

An account is provided of the world’s ten most feared fungi. Within areas of interest, we have organized the entries in the order of concern. We put four human pathogens first as this is of concern to most people. This is followed by fungi producing mycotoxins that are highly harmful for humans; Aspergillus flavus, the main producer of aflatoxins, was used as an example. Problems due to indoor air fungi may also directly affect our health and we use Stachybotrys chartarum as an example. Not everyone collects and eats edible mushrooms. However, fatalities caused by mushroom intoxications often make news headlines and therefore we include one of the most poisonous of all mushrooms, Amanita phalloides, as an example. We then move on to the fungi that damage our dwellings causing serious anxiety by rotting our timber structures and flooring. Serpula lacrymans, which causes dry rot is an excellent example. The next example serves to represent all plant and forest pathogens. Here we chose Austropuccinia psidii as it is causing devastating effects in Australia and will probably do likewise in New Zealand. Finally, we chose an important amphibian pathogen which is causing serious declines in the numbers of frogs and other amphibians worldwide. Although we target the top ten most feared fungi, numerous others are causing serious concern to human health, plant production, forestry, other animals and our factories and dwellings. By highlighting ten feared fungi as an example, we aim to promote public awareness of the cost and importance of fungi.

Malassezia are lipid dependent basidiomycetous yeasts that inhabit the skin and mucosa of humans and other warm-blooded animals, and are a major component of the skin microbiome. They occur as skin commensals, but are also associated with various skin disorders and bloodstream infections. The genus currently comprises 17 species and has recently been assigned its own class, Malasseziomycetes. Importantly, multiple Malassezia species and/or genotypes may cause unique or similar pathologies and vary in their antifungal susceptibility. In addition to culture-based approaches, culture-independent methods have added to our understanding of Malassezia presence and abundance and their relationship to pathogenicity. Moreover, these novel approaches have suggested a much wider-spread presence, including other human body parts and even other ecosystems, but their role in these arenas requires further clarification. With recent successful transformation and genetic engineering of Malassezia, the role of specific genes in pathogenesis can now be studied. We suggest that characterizing the metabolic impact of Malassezia communities rather than species identification is key in elucidation of pathophysiological associations. Finally, the increasing availability of genome sequences may provide key information aiding faster diagnostics, and understanding of the biochemical mechanisms for Malassezia skin adaptation and the design of future drugs.

System designers make trade-offs between metrics of interest such as execution time, functional quality and cost to create a properly balanced system. Execution traces, which are sequences of timestamped start and end events of system tasks, are a general and powerful means to understand the system behavior that gives rise to these trade-offs. Such traces can be produced by, e.g., executable models or prototype systems. Their interpretation, however, often is non-trivial. We present two automated analysis techniques that work on execution traces to help the system designer with interpretation. First, critical-path analysis can be used to answer the typical “what is the bottleneck” question, and we extend earlier work of [16] with a technique that uses application information to refine the analysis. Second, we define a pseudo-metric on execution traces, which is useful for calibration and validation purposes, and which can be used to visualize the differences between traces. Both techniques are based on a common graph representation of execution traces. We have implemented our techniques in the Trace visualization tool [12], and have applied them in a case study from the digital printing domain.

Dichomitus squalens is a white-rot fungus that colonizes and grows mainly on softwood and is commonly found in the northern parts of Europe, North America, and Asia. We analyzed the genetic and physiological diversity of eight D. squalens monokaryons derived from a single dikaryon. In addition, an unrelated dikaryon and a newly established dikaryon from two of the studied monokaryons were included. Both growth and lignocellulose acting enzyme profiles were highly variable between the studied monokaryotic and dikaryotic strains, demonstrating a high level of diversity within the species.

Mucormycosis is a rare fungal infection caused by Mucor indicus. Phylogenetic analysis of many M. indicus isolates, mainly sampled from different clinical and environmental specimens collected worldwide, revealed two genotypes, I and II, based on ITS and D1/D2 LSU rDNA sequences. A retrospective review of the literature revealed 13 cases. Eight (76.9%) patients had disseminated infections, and the overall mortality rate was 30.7%. A pulmonary infection caused by M. indicus genotype I in a liver transplant recipient was disseminated to include the skin and was successfully treated with liposomal amphotericin B and aggressive surgery. M. indicus can infect a wide variety of patients with no real preference for the site of infection. We concluded that M. indicus has emerged as a significant cause of invasive mycosis in severely immunocompromised patients worldwide. Early diagnosis and initiation of appropriate therapy could enhance survival in these immunocompromised patient populations.

PubMedID: 30953839 A total of 476 European isolates (310 Cryptococcus neoformans var. grubii, 150 C. neoformans var. neoformans, and 16 C. gattii species complex) from both clinical and environmental sources were analyzed by multi-locus sequence typing. Phylogenetic and population genetic analyses were performed. Sequence analysis identified 74 sequence types among C. neoformans var. neoformans (VNIV), 65 among C. neoformans var. grubii (56 VNI, 8 VNII, 1 VNB), and 5 among the C. gattii species complex (4 VGI and 1 VGIV) isolates. ST23 was the most frequent genotype (22%) among VNI isolates which were mostly grouped in a large clonal cluster including 50% of isolates. Among VNIV isolates, a predominant genotype was not identified. A high percentage of autochthonous STs were identified in both VNI (71%) and VNIV (96%) group of isolates. The 16 European C. gattii species complex isolates analyzed in the present study originated all from the environment and all belonged to a large cluster endemic in the Mediterranean area. Population genetic analysis confirmed that VNI group of isolates were characterized by low variability and clonal expansion while VNIV by a higher variability and a number of recombination events. However, when VNI and VNIV environmental isolates were compared, they showed a similar population structure with a high percentage of shared mutations and the absence of fixed mutations. Also linkage disequilibrium analysis reveals differences between clinical and environmental isolates showing a key role of PLB1 allele combinations in host infection as well as the key role of LAC1 allele combinations for survival of the fungus in the environment. The present study shows that genetic comparison of clinical and environmental isolates represents a first step to understand the genetic characteristics that cause the shift of some genotypes from a saprophytic to a parasitic life style. © 2019 Elsevier Inc. Fundação para a Ciência e a Tecnologia National and Kapodistrian University of Athens APP1031943 70/3/6915, 70/4/5905 POCI-01-0145-FEDER-006958, UID/AGR/04033/2019 We thank Dr. Kwon Chung and Prof. Dromer for contribution in the critical reading of the manuscript. The findings and conclusions in this manuscript are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention. W Meyer and S Lockhart were supported by an NH&MRC grant # APP1031943 . AC Sampaio was supported by Fundação para a Ciência e Tecnologia and FEDER/COMPETE/POCI provided to CITAB under the projects POCI-01-0145-FEDER-006958 and UID/AGR/04033/2019. A Velegraki was supported by SARG K.A.70/4/5905 and 70/3/6915, National and Kapodistrian University of Athens and the Bodosakis Foundation , Athens, Greece.

Cystic fibrosis (CF) patients are colonized with a multitude of bacteria and fungi. From respiratory samples of two CF patients in our institute, a difficult to identify yeast was isolated repeatedly. This yeast was eventually identified as Cutaneotrichosporon (Cryptococcus) cyanovorans by internal transcribed spacer (ITS) and ribosomal large subunit (LSU) sequencing. C. cyanovorans is a basidiomycetous yeast originally reported as environmental isolate from South African soil and has not been described before as clinical isolate from CF patients. Keywords: Cryptococcus cyanovorans, Cutaneotrichosporon cyanovorans, Cystic fibrosis, MADLITOF-MS

Various Talaromyces strains were isolated during a survey of fungi involved in leaf litter decomposition in tropical lowland forests in the Caquetá and Amacayacu areas of the Colombian Amazon. Four new Talaromyces species are described using a polyphasic approach, which includes phenotypic characters, extrolite profiles and phylogenetic analysis of the internal transcribed spacer region (ITS) barcode, and beta-tubulin (BenA) and calmodulin (CaM) gene regions. Talaromyces amazonensis sp. nov., T. francoae sp. nov. and T. purgamentorum sp. nov. belong to Talaromyces section Talaromyces, and T. columbiensis sp. nov. is located in section Bacillispori. The new species produce several bioactive compounds: T. amazonensis produces the potential anticancer agents duclauxin, berkelic acid and vermicillin, and T. columbiensis produces the effective anticancer agent wortmannin (together with duclauxin). In addition to the new species, T. aculeatus and T. macrosporus were isolated during this study on leaf litter decomposition.

The subphylum Ustilaginomycotina (Basidiomycota, Fungi) comprises mainly plant pathogenic fungi (smuts). Some of the lineages possess cultivable unicellular stages that are usually classified as yeast or yeast-like species in a largely artificial taxonomic system which is independent from and largely incompatible with that of the smut fungi. Here we performed phylogenetic analyses based on seven genes including three nuclear ribosomal RNA genes and four protein coding genes to address the molecular phylogeny of the ustilaginomycetous yeast species and their filamentous counterparts. Taxonomic revisions were proposed to reflect this phylogeny and to implement the ‘One Fungus = One Name’ principle. The results confirmed that the yeast-containing classes Malasseziomycetes, Moniliellomycetes and Ustilaginomycetes are monophyletic, whereas Exobasidiomycetes in the current sense remains paraphyletic. Four new genera, namely Dirkmeia gen. nov., Kalmanozyma gen. nov., Golubevia gen. nov. and Robbauera gen. nov. are proposed to accommodate Pseudozyma and Tilletiopsis species that are distinct from the other smut taxa and belong to clades that are separate from those containing type species of the hitherto described genera. Accordingly, new orders Golubeviales ord. nov. with Golubeviaceae fam. nov. and Robbauerales ord. nov. with Robbaueraceae fam. nov. are proposed to accommodate the sisterhood of Golubevia gen. nov. and Robbauera gen. nov. with other orders of Exobasidiomycetes. The majority of the remaining anamorphic yeast species are transferred to corresponding teleomorphic genera based on strongly supported phylogenetic affinities, resulting in the proposal of 28 new combinations. The taxonomic status of a few Pseudozyma species remains to be determined because of their uncertain phylogenetic positions. We propose to use the term pro tempore or pro tem. in abbreviation to indicate the single-species lineages that are temporarily maintained.

The Tremellomycetes (Basidiomycota) contains a large number of unicellular and dimorphic fungi with stable free-living unicellular states in their life cycles. These fungi have been conventionally classified as basidiomycetous yeasts based on physiological and biochemical characteristics. Many currently recognised genera of these yeasts are mainly defined based on phenotypical characters and are highly polyphyletic. Here we reconstructed the phylogeny of the majority of described anamorphic and teleomorphic tremellomycetous yeasts using Bayesian inference, maximum likelihood, and neighbour-joining analyses based on the sequences of seven genes, including three rRNA genes, namely the small subunit of the ribosomal DNA (rDNA), D1/D2 domains of the large subunit rDNA, and the internal transcribed spacer regions (ITS 1 and 2) of rDNA including 5.8S rDNA; and four protein-coding genes, namely the two subunits of the RNA polymerase II (RPB1 and RPB2), the translation elongation factor 1-α (TEF1) and the mitochondrial gene cytochrome b (CYTB). With the consideration of morphological, physiological and chemotaxonomic characters and the congruence of phylogenies inferred from analyses using different algorithms based on different data sets consisting of the combined seven genes, the three rRNA genes, and the individual protein-coding genes, five major lineages corresponding to the orders Cystofilobasidiales, Filobasidiales, Holtermanniales, Tremellales, and Trichosporonales were resolved. A total of 45 strongly supported monophyletic clades with multiple species and 23 single species clades were recognised. This phylogenetic framework will be the basis for the proposal of an updated taxonomic system of tremellomycetous yeasts that will be compatible with the current taxonomic system of filamentous basidiomycetes accommodating the ‘one fungus, one name’ principle.

Phylogenetic analysis of 11 genetic loci and results from many genotyping studies revealed significant genetic diversity with the pathogenic Cryptococcus gattii/Cryptococcus neoformans species complex. Genealogical concordance, coalescence-based, and species tree approaches supported the presence of distinct and concordant lineages within the complex. Consequently, we propose to recognize the current C. neoformans var. grubii and C. neoformans var. neoformans as separate species, and five species within C. gattii. The type strain of C. neoformans CBS132 represents a serotype AD hybrid and is replaced. The newly delimited species differ in aspects of pathogenicity, prevalence for patient groups, as well as biochemical and physiological aspects, such as susceptibility to antifungals. MALDI-TOF mass spectrometry readily distinguishes the newly recognized species.

Cryptococcosis is a major fungal disease caused by members of the Cryptococcus gattii and Cryptococcus neoformans species complexes. After more than 15 years of molecular genetic and phenotypic studies and much debate, a proposal for a taxonomic revision was made., Cryptococcosis is a major fungal disease caused by members of the Cryptococcus gattii and Cryptococcus neoformans species complexes. After more than 15 years of molecular genetic and phenotypic studies and much debate, a proposal for a taxonomic revision was made. The two varieties within C. neoformans were raised to species level, and the same was done for five genotypes within C. gattii. In a recent perspective (K. J. Kwon-Chung et al., mSphere 2:e00357-16, 2017, https://doi.org/10.1128/mSphere.00357-16), it was argued that this taxonomic proposal was premature and without consensus in the community. Although the authors of the perspective recognized the existence of genetic diversity, they preferred the use of the informal nomenclature “C. neoformans species complex” and “C. gattii species complex.” Here we highlight the advantage of recognizing these seven species, as ignoring these species will impede deciphering further biologically and clinically relevant differences between them, which may in turn delay future clinical advances.

SummaryRecognition of fungal pathogens by C-type lectin receptor (CLR) dectin-1 on human dendritic cells is essential for triggering protective antifungal TH1 and TH17 immune responses. We show that Fonsecaea monophora, a causative agent of chromoblastomycosis, a chronic fungal skin infection, evades these antifungal responses by engaging CLR mincle and suppressing IL-12, which drives TH1 differentiation. Dectin-1 triggering by F. monophora activates transcription factor IRF1, which is crucial for IL12A transcription via nucleosome remodeling. However, simultaneous F. monophora binding to mincle induces an E3 ubiquitin ligase Mdm2-dependent degradation pathway, via Syk-CARD9-mediated PKB signaling, that leads to loss of nuclear IRF1 activity, hence blocking IL12A transcription. The absence of IL-12 leads to impaired TH1 responses and promotes TH2 polarization. Notably, mincle is similarly exploited by other chromoblastomycosis-associated fungi to redirect TH responses. Thus, mincle is a fungal receptor that can suppress antifungal immunity and, as such, is a potential therapeutic target.

Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) was used for an extensive identification study of arthroconidial yeasts, using 85 reference strains from the CBS-KNAW yeast collection and 134 clinical isolates collected from medical centers in Qatar, Greece, and Romania. The test set included 72 strains of ascomycetous yeasts ( Galactomyces , Geotrichum , Saprochaete , and Magnusiomyces spp.) and 147 strains of basidiomycetous yeasts ( Trichosporon and Guehomyces spp.). With minimal preparation time, MALDI-TOF MS proved to be an excellent diagnostic tool that provided reliable identification of most (98%) of the tested strains to the species level, with good discriminatory power. The majority of strains were correctly identified at the species level with good scores (>2.0) and seven of the tested strains with log score values between 1.7 and 2.0. The MALDI-TOF MS results obtained were consistent with validated internal transcribed spacer (ITS) and/or large subunit (LSU) ribosomal DNA sequencing results. Expanding the mass spectrum database by increasing the number of reference strains for closely related species, including those of nonclinical origin, should enhance the usefulness of MALDI-TOF MS-based diagnostic analysis of these arthroconidial fungi in medical and other laboratories.

Susceptibility testing using the EUCAST-AFST method against 39 clinical Fusarium strains consecutively collected from local and invasive infections during the last 10years assessed the in vitro activities of amphotericin B (AmB) and triazole antifungal agents. In addition, the susceptibility pattern of 12 reference strains from the CBS-KNAW Fungal Biodiversity Centre (CBS) was evaluated. In particular Fusarium petroliphilum and F. solani sensu lato were involved in disseminated infections and known for treatment failure. AmB displayed the lowest MICs followed by voriconazole VRC, posaconazole (POC). Itraconazole (ITC) showed high MIC values, displaying in vitro resistance. Clinical isolates were significantly (P

Most small genera containing yeast species in the Pucciniomycotina (Basidiomycota, Fungi) are monophyletic, whereas larger genera including Bensingtonia, Rhodosporidium, Rhodotorula, Sporidiobolus and Sporobolomyces are polyphyletic. With the implementation of the “One Fungus = One Name” nomenclatural principle these polyphyletic genera were revised. Nine genera, namely Bannoa, Cystobasidiopsis, Colacogloea, Kondoa, Erythrobasidium, Rhodotorula, Sporobolomyces, Sakaguchia and Sterigmatomyces, were emended to include anamorphic and teleomorphic species based on the results obtained by a multi-gene phylogenetic analysis, phylogenetic network analyses, branch length-based methods, as well as morphological, physiological and biochemical comparisons. A new class Spiculogloeomycetes is proposed to accommodate the order Spiculogloeales. The new families Buckleyzymaceae with Buckleyzyma gen. nov., Chrysozymaceae with Chrysozyma gen. nov., Microsporomycetaceae with Microsporomyces gen. nov., Ruineniaceae with Ruinenia gen. nov., Symmetrosporaceae with Symmetrospora gen. nov., Colacogloeaceae and Sakaguchiaceae are proposed. The new genera Bannozyma, Buckleyzyma, Fellozyma, Hamamotoa, Hasegawazyma, Jianyunia, Rhodosporidiobolus, Oberwinklerozyma, Phenoliferia, Pseudobensingtonia, Pseudohyphozyma, Sampaiozyma, Slooffia, Spencerozyma, Trigonosporomyces, Udeniozyma, Vonarxula, Yamadamyces and Yunzhangia are proposed to accommodate species segregated from the genera Bensingtonia, Rhodosporidium, Rhodotorula, Sporidiobolus and Sporobolomyces. Ballistosporomyces is emended and reintroduced to include three Sporobolomyces species of the sasicola clade. A total of 111 new combinations are proposed in this study.