ABSTRACT
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.
Subject(s)
Ascomycota/classification , Ascomycota/genetics , DNA, Fungal/genetics , Mycoses/microbiology , Phylogeny , Ascomycota/isolation & purification , Ascomycota/pathogenicity , DNA, Ribosomal Spacer/genetics , Humans , RNA, Ribosomal, 28S/genetics , Sequence Analysis, DNA , Subcutaneous Tissue/microbiologyABSTRACT
Scientific communication is facilitated by a data-driven, scientifically sound taxonomy that considers the end-user's needs and established successful practice. In 2013, the Fusarium community voiced near unanimous support for a concept of Fusarium that represented a clade comprising all agriculturally and clinically important Fusarium species, including the F. solani species complex (FSSC). Subsequently, this concept was challenged in 2015 by one research group who proposed dividing the genus Fusarium into seven genera, including the FSSC described as members of the genus Neocosmospora, with subsequent justification in 2018 based on claims that the 2013 concept of Fusarium is polyphyletic. Here, we test this claim and provide a phylogeny based on exonic nucleotide sequences of 19 orthologous protein-coding genes that strongly support the monophyly of Fusarium including the FSSC. We reassert the practical and scientific argument in support of a genus Fusarium that includes the FSSC and several other basal lineages, consistent with the longstanding use of this name among plant pathologists, medical mycologists, quarantine officials, regulatory agencies, students, and researchers with a stake in its taxonomy. In recognition of this monophyly, 40 species described as genus Neocosmospora were recombined in genus Fusarium, and nine others were renamed Fusarium. Here the global Fusarium community voices strong support for the inclusion of the FSSC in Fusarium, as it remains the best scientific, nomenclatural, and practical taxonomic option available.
Subject(s)
Fusarium , Fusarium/genetics , Phylogeny , Plant Diseases , PlantsABSTRACT
Chrysosporium-related fungi, the cause of superficial and deep mycoses, are an emerging infectious disease affecting not only reptiles but also immunocompromized humans. However, the information on Nannizziopsis arthrosporioides is extremely scarce. We herein characterized N. arthrosporioides isolated from a Cuban rock iguana (Cyclura nubila). Three skin ulcers were found in a Cuban rock iguana after captivity for 8 years. Microscopic examination revealed hyperplastic, hyperkeratotic, and ulcerative dermatitis coupled with numerous branched, septate fungal hyphae. The fungal culture yielded growth of zonate, felted cottony-powdery colonies with lobate margins on medium. Maximum-likelihood phylogeny tree based on the combined partial actin and partial ß-tubulin genes demonstrated that current isolates were mostly close to N. arthrosporioides. Furthermore, antifungal susceptibility test demonstrated that N. arthrosporioides had lowest minimal inhibitory concentration (MIC) values to isavuconazole, efinaconazole, and luliconazole, which may be the potential treatment of choice for N. arthrosporioides infection. The current study describes the first confirmed case of dermatomycosis caused by N. arthrosporioides of a captive reptile in Asia with detailed descriptions of the clinical, histopathological, and mycological features. The current findings provide new information on global distribution and host range of N. arthrosporioides and can raise the concern on the transboundary or emerging disease of N. arthrosporioides in Asian region.
Subject(s)
Dermatomycoses , Iguanas , Onygenales , Animals , Antifungal Agents/pharmacology , Asia , Dermatomycoses/drug therapy , Dermatomycoses/microbiology , Humans , Iguanas/microbiology , Microbial Sensitivity Tests , Onygenales/drug effects , Onygenales/isolation & purificationABSTRACT
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.
Subject(s)
Ascomycota/pathogenicity , Communicable Diseases, Emerging/microbiology , Dermatomycoses/epidemiology , Opportunistic Infections/epidemiology , Antifungal Agents , Ascomycota/drug effects , Ascomycota/genetics , Communicable Diseases, Emerging/epidemiology , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Dermatomycoses/microbiology , Humans , Opportunistic Infections/microbiology , Phenotype , Phylogeny , RNA, Ribosomal, 28S/genetics , Retrospective Studies , Sequence Analysis, DNA , Spain/epidemiologyABSTRACT
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.
Subject(s)
Ascomycota/classification , Mycoses/microbiology , Phylogeny , Ascomycota/isolation & purification , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Humans , Hyphae , RNA, Ribosomal, 28S/genetics , Sequence Analysis, DNA , Spores, FungalABSTRACT
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.
Subject(s)
Ascomycota/classification , Ascomycota/genetics , DNA, Fungal/chemistry , DNA, Fungal/genetics , Molecular Diagnostic Techniques/methods , Mycoses/diagnosis , Sequence Analysis, DNA/methods , Humans , Mycoses/microbiologyABSTRACT
Mycopathologia was founded in 1938 to 'diffuse the understanding of fungal diseases in man and animals among mycologists.' This was an important mission considering that pathogenic fungi for humans and animals represent a tiny minority of the estimated 1.5-5 million fungal inhabitants on Earth. These pathogens have diverged from the usual saprotrophic lifestyles of most fungi to colonize and infect humans and animals. Medical and veterinary mycology is the subdiscipline of microbiology that dwells into the mysteries of parasitic, fungal lifestyles. Among the oldest continuing scientific publications on the subject, Mycopathologia had its share of 'classic papers' since the first issue was published in 1938. An analysis of the eight decades of notable contributions reveals many facets of host-pathogen interactions among 183 volumes comprising about 6885 articles. We have analyzed the impact and relevance of this body of work using a combination of citation tools (Google Scholar and Scopus) since no single citation metric gives an inclusive perspective. Among the highly cited Mycopathologia publications, those on experimental mycology accounted for the major part of the articles (36%), followed by diagnostic mycology (16%), ecology and epidemiology (15%), clinical mycology (14%), taxonomy and classification (10%), and veterinary mycology (9%). The first classic publication, collecting nearly 200 citations, appeared in 1957, while two articles published in 2010 received nearly 150 citations each, which is notable for a journal covering a highly specialized field of study. An empirical analysis of the publication trends suggests continuing interests in novel diagnostics, fungal pathogenesis, review of clinical diseases especially with relevance to the laboratory scientists, taxonomy and classification of fungal pathogens, fungal infections and carriage in pets and wildlife, and changing ecology and epidemiology of fungal diseases around the globe. We anticipate that emerging and re-emerging fungal pathogens will continue to cause significant health burden in the coming decades. It remains vital that scientists and physicians continue to collaborate by learning each other's language for the study of fungal diseases, and Mycopathologia will strive to be their partner in this increasingly important endeavor to its 100th anniversary in 2038 and beyond.
Subject(s)
Bibliometrics , Fungi/physiology , Host-Pathogen Interactions , Mycology/history , Mycoses/microbiology , Mycoses/veterinary , Periodicals as Topic , Animals , History, 20th Century , History, 21st Century , Humans , Retrospective StudiesABSTRACT
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.
Subject(s)
Ascomycota/classification , Ascomycota/isolation & purification , Mycoses/microbiology , Antifungal Agents/pharmacology , Ascomycota/cytology , Ascomycota/drug effects , Cluster Analysis , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Genes, rRNA , Humans , Microbial Sensitivity Tests , Phylogeny , RNA, Fungal/genetics , RNA, Ribosomal/genetics , Sequence Analysis, DNA , United States , Wounds and Injuries/complicationsABSTRACT
The genus Talaromyces constitutes an important group of molds with species that are mainly found in soil, indoor environments and food products. Traditionally, it has been considered, together with Eupenicillium, the teleomorphic state of Penicillium. However, the taxonomy of these fungi has changed considerably, and Talaromyces currently includes sexually and asexually reproducing species. In a previous study of the occurrence of penicillium-like fungi from clinical samples in the USA, we used the combined phylogeny of the internal transcribed spacer (ITS) region of the rDNA and ß-tubulin (BenA) gene to identify 31 isolates of Talaromyces, 85 of Penicillium and two of Rasamsonia. However, seven isolates of Talaromyces were assigned to the corresponding sections but not to any particular species. In this study, we have resolved the taxonomy of these isolates through a multilocus sequence analysis of the ITS, fragments of the BenA, calmodulin (CaM), and RNA polymerase II second largest subunit (RPB2) genes, and a detailed phenotypic study. As a result, four new species are described and illustrated, ie Talaromyces alveolaris, T. georgiensis, T. minnesotensis and T. rapidus.
Subject(s)
Mycoses/microbiology , Talaromyces/classification , Talaromyces/isolation & purification , DNA, Fungal/genetics , DNA, Ribosomal , DNA, Ribosomal Spacer , Humans , Multilocus Sequence Typing , Penicillium/genetics , Phenotype , Phylogeny , Tubulin/geneticsABSTRACT
The new species Spiromastigoides albida (Onygenales, Eurotiomycetes, Ascomycota), from a lung biopsy in USA, is proposed and described based on morphological data and the analysis of rRNA, and fragments of actin and ß-tubulin gene sequences. This species is characterized by white colonies and a malbranchea-like asexual morph with profusely branching curved conidiophores forming sporodochia-like structures. Moreover, new combinations for Gymnoascus alatosporus, and for some new species recently described under the generic name Spiromastix, are provided.
Subject(s)
Lung/microbiology , Mycoses/microbiology , Onygenales , Biopsy , DNA, Fungal/genetics , Humans , Mycoses/diagnosis , Onygenales/classification , Onygenales/genetics , Onygenales/isolation & purification , Phylogeny , RNA, Ribosomal/genetics , Spores, Fungal/classificationABSTRACT
Penicillium species are some of the most common fungi observed worldwide and have an important economic impact as well as being occasional agents of human and animal mycoses. A total of 118 isolates thought to belong to the genus Penicillium based on morphological features were obtained from the Fungus Testing Laboratory at the University of Texas Health Science Center in San Antonio (United States). The isolates were studied phenotypically using standard growth conditions. Molecular identification was made using two genetic markers, the internal transcribed spacer (ITS) and a fragment of the ß-tubulin gene. In order to assess phylogenetic relationships, maximum likelihood and Bayesian inference assessments were used. Antifungal susceptibility testing was performed according to CLSI document M38-A2 for nine antifungal drugs. The isolates were identified within three genera, i.e., Penicillium, Talaromyces, and Rasamsonia The most frequent species in our study were Penicillium rubens, P. citrinum, and Talaromyces amestolkiae The potent in vitro activity of amphotericin B (AMB) and terbinafine (TRB) and of the echinocandins against Penicillium and Talaromyces species might offer a good therapeutic alternative for the treatment of infections caused by these fungi.
Subject(s)
Antifungal Agents/pharmacology , Eurotiales/drug effects , Eurotiales/isolation & purification , Mycoses/diagnosis , Animals , Cluster Analysis , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Eurotiales/classification , Eurotiales/genetics , Humans , Microbial Sensitivity Tests , Mycological Typing Techniques , Mycoses/veterinary , Phylogeny , Sequence Analysis, DNA , Tubulin/genetics , United StatesABSTRACT
Cladosporium species are ubiquitous, saprobic, dematiaceous fungi, only infrequently associated with human and animal opportunistic infections. We have studied a large set of Cladosporium isolates recovered from clinical samples in the United States to ascertain the predominant species there in light of recent taxonomic changes in this genus and to determine whether some could possibly be rare potential pathogens. A total of 92 isolates were identified using phenotypic and molecular methods, which included sequence analysis of the internal transcribed spacer (ITS) region and a fragment of the large subunit (LSU) of the nuclear ribosomal DNA (rDNA), as well as fragments of the translation elongation factor 1 alpha (EF-1α) and actin (Act) genes. The most frequent species was Cladosporium halotolerans (14.8%), followed by C. tenuissimum (10.2%), C. subuliforme (5.7%), and C. pseudocladosporioides (4.5%). However, 39.8% of the isolates did not correspond to any known species and were deemed to comprise at least 17 new lineages for Cladosporium. The most frequent anatomic site of isolation was the respiratory tract (54.5%), followed by superficial (28.4%) and deep tissues and fluids (14.7%). Species of the two recently described cladosporiumlike genera Toxicocladosporium and Penidiella are reported for the first time from clinical samples. In vitro susceptibility testing of 92 isolates against nine antifungal drugs showed a variety of results but high activity overall for the azoles, echinocandins, and terbinafine.
Subject(s)
Cladosporium/classification , Cladosporium/isolation & purification , Environmental Microbiology , Mycoses/epidemiology , Mycoses/microbiology , Actins/genetics , Animals , Antifungal Agents/pharmacology , Cladosporium/genetics , Cluster Analysis , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Humans , Microbial Sensitivity Tests , Molecular Sequence Data , Peptide Elongation Factor 1/genetics , Phylogeny , RNA, Ribosomal/genetics , Sequence Analysis, DNA , United States/epidemiologyABSTRACT
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.
Subject(s)
Ascomycota/classification , Sordariales/classification , Ascomycota/genetics , Ascomycota/growth & development , Ascomycota/isolation & purification , DNA, Fungal/genetics , DNA, Ribosomal/genetics , Fungal Proteins/genetics , Molecular Sequence Data , Phylogeny , RNA Polymerase II/genetics , Soil Microbiology , Sordariales/genetics , Sordariales/growth & development , Sordariales/isolation & purification , Spores, Fungal/classification , Spores, Fungal/genetics , Spores, Fungal/growth & development , Spores, Fungal/isolation & purificationABSTRACT
A case of fungal necrotizing fasciitis that appeared in an immunocompetent Mexican woman after a car accident is described. The patient did not respond to antifungal treatment and died 4 days later. The fungus was molecularly identified as a new species of Apophysomyces, namely, Apophysomyces mexicanus.
Subject(s)
Fasciitis, Necrotizing/diagnosis , Fasciitis, Necrotizing/microbiology , Mucorales/isolation & purification , Mucormycosis/diagnosis , Mucormycosis/microbiology , Accidents, Traffic , Antifungal Agents/therapeutic use , DNA, Fungal/chemistry , DNA, Fungal/genetics , Fatal Outcome , Female , Humans , Mexico , Middle Aged , Molecular Sequence Data , Mucorales/classification , Mucorales/genetics , Sequence Analysis, DNA , Treatment Failure , Wounds and Injuries/complicationsABSTRACT
A set of 73 isolates of the emerging fungus Trichoderma isolated from human and animal clinical specimens were characterized morphologically and molecularly using a multilocus sequence analysis that included the internal transcribed spacer (ITS) regions of the nuclear ribosomal DNA and fragments of the translation elongation factor 1 alpha (Tef1), endochitinase CHI18-5 (Chi18-5), and actin 1 (Act1) genes. The most frequent species was Trichoderma longibrachiatum (26%), followed by Trichoderma citrinoviride (18%), the Hypocrea lixii/Trichoderma harzianum species complex (15%), the newly described species Trichoderma bissettii (12%), and Trichoderma orientale (11%). The most common anatomical sites of isolation in human clinical specimens were the respiratory tract (40%), followed by deep tissue (30%) and superficial tissues (26%), while all the animal-associated isolates were obtained from superficial tissue samples. Susceptibilities of the isolates to eight antifungal drugs in vitro showed mostly high MICs, except for voriconazole and the echinocandins.
Subject(s)
Antifungal Agents/pharmacology , Communicable Diseases, Emerging/microbiology , Mycoses/microbiology , Mycoses/veterinary , Phylogeny , Trichoderma/classification , Trichoderma/drug effects , Actins/genetics , Animals , Chitinases/genetics , Cluster Analysis , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Humans , Microbial Sensitivity Tests , Molecular Sequence Data , Multilocus Sequence Typing , Peptide Elongation Factor 1/genetics , Trichoderma/genetics , Trichoderma/isolation & purificationABSTRACT
The Mediterranean Sea stands out as a hotspot of biodiversity, whose fungal composition remains underexplored. Marine sediments represent the most diverse substrate; however, the challenge of recovering fungi in culture hinders the precise identification of this diversity. Concentration techniques like skimmed milk flocculation (SMF) could represent a suitable solution. Here, we compare the effectiveness in recovering filamentous ascomycetes of direct plating and SMF in combination with three culture media and two incubation temperatures, and we describe the fungal diversity detected in marine sediments. Sediments were collected at different depths on two beaches (Miracle and Arrabassada) on the Spanish western Mediterranean coast between 2021 and 2022. We recovered 362 strains, and after a morphological selection, 188 were identified primarily with the LSU and ITS barcodes, representing 54 genera and 94 species. Aspergillus, Penicillium, and Scedosporium were the most common genera, with different percentages of abundance between both beaches. Arrabassada Beach was more heterogeneous, with 42 genera representing 60 species (Miracle Beach, 28 genera and 54 species). Although most species were recovered with direct plating (70 species), 20 species were exclusively obtained using SMF as a sample pre-treatment, improving our ability to detect fungi in culture. In addition, we propose three new species in the genera Exophiala, Nigrocephalum, and Queenslandipenidiella, and a fourth representing the novel genus Schizochlamydosporiella. We concluded that SMF is a useful technique that, in combination with direct plating, including different culture media and incubation temperatures, improves the chance of recovering marine fungal communities in culture-dependent studies.
ABSTRACT
During the course of a project investigating culturable Ascomycota diversity from freshwater sediments in Spain, we isolated 63 strains of cycloheximide-resistant fungi belonging to the order Onygenales. These well-known ascomycetes, able to infect both humans and animals, are commonly found in terrestrial habitats, colonizing keratin-rich soils or dung. Little is known about their diversity in aquatic environments. Combining morphological features and sequence analyses of the ITS and LSU regions of the nrDNA, we identified 14 species distributed in the genera Aphanoascus, Arachniotus, Arthroderma, Arthropsis, Emmonsiellopsis, Gymnoascoideus, Leucothecium, Malbranchea, and Myriodontium. Furthermore, three novel species for the genus Malbranchea are proposed as M. echinulata sp. nov., M. irregularis sp. nov., and M. sinuata sp. nov. The new genera Albidomyces and Neoarthropsis are introduced based on Arachniotus albicans and Arthropsis hispanica, respectively. Neoarthropsis sexualis sp. nov. is characterized and differentiated morphologically from its counterpart by the production of a sexual morph. The novel family Neoarthropsidaceae is proposed for the genera Albidomyes, Apinisia, Arachnotheca, Myriodontium, and Neoarthropsis, based on their phylogenetic relationships and phenotypic and ecological traits. Pseudoamaurascopsis gen. nov. is introduced to accommodate P. spiralis sp. nov., a fungus with unclear taxonomy related to Amaurascopsis and Polytolypa. We traced the ecology and global distribution of the novel fungi through ITS environmental sequences deposited in the GlobalFungi database. Studying the fungal diversity from freshwater sediments not only contributes to filling gaps in the relationships and taxonomy of the Ascomycota but also gives us insights into the fungal community that might represent a putative risk to the health of animals and humans inhabiting or transient in aquatic environments.
ABSTRACT
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.
Subject(s)
Ascomycota , Spain , Ascomycota/genetics , Fungi , Spores, FungalABSTRACT
Although the Pleosporaceae is one of the species-richest families in the Pleosporales, research into less-explored substrates can contribute to widening the knowledge of its diversity. In our ongoing survey on culturable Ascomycota from freshwater sediments in Spain, several pleosporacean specimens of taxonomic interest were isolated. Phylogenetic analyses based on five gene markers (ITS, LSU, gapdh, rbp2, and tef1) revealed that these fungi represent so far undescribed lineages, which are proposed as two novel genera in the family, i.e., Neostemphylium typified by Neostemphylium polymorphum sp. nov., and Scleromyces to accommodate Scleromyces submersus sp. nov. Neostemphylium is characterized by the production of phaeodictyospores from apically swollen and darkened conidiogenous cells, the presence of a synanamorph that consists of cylindrical and brown phragmoconidia growing terminally or laterally on hyphae, and by the ability to produce secondary conidia by a microconidiation cycle. Scleromyces is placed phylogenetically distant to any genera in the family and only produces sclerotium-like structures in vitro. The geographic distribution and ecology of N. polymorphum and Sc. submersus were inferred from metabarcoding data using the GlobalFungi database. The results suggest that N. polymorphum is a globally distributed fungus represented by environmental sequences originating primarily from soil samples collected in Australia, Europe, and the USA, whereas Sc. submersus is a less common species that has only been found associated with one environmental sequence from an Australian soil sample. The phylogenetic analyses of the environmental ITS1 and ITS2 sequences revealed at least four dark taxa that might be related to Neostemphylium and Scleromyces. The phylogeny presented here allows us to resolve the taxonomy of the genus Asteromyces as a member of the Pleosporaceae.
ABSTRACT
Soil is one of the main reservoirs of fungi. The aim of this study was to study the richness of ascomycetes in a set of soil samples from Mexico and Spain. Fungi were isolated after 2% w/v phenol treatment of samples. In that way, several strains of the genus Penicillium were recovered. A phylogenetic analysis based on internal transcribed spacer (ITS), beta-tubulin (BenA), calmodulin (CaM), and RNA polymerase II subunit 2 gene (rpb2) sequences showed that four of these strains had not been described before. Penicillium melanosporum produces monoverticillate conidiophores and brownish conidia covered by an ornate brown sheath. Penicillium michoacanense and Penicillium siccitolerans produce sclerotia, and their asexual morph is similar to species in the section Aspergilloides (despite all of them pertaining to section Lanata-Divaricata). P. michoacanense differs from P. siccitolerans in having thick-walled peridial cells (thin-walled in P. siccitolerans). Penicillium sexuale differs from Penicillium cryptum in the section Crypta because it does not produce an asexual morph. Its ascostromata have a peridium composed of thick-walled polygonal cells, and its ascospores are broadly lenticular with two equatorial ridges widely separated by a furrow. All four new species are xerophilic. Despite the genus Penicillium containing more than 480 known species, they are rarely reported as xerophilic.