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1.
Mycopathologia ; 185(4): 613-627, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32710392

RESUMO

Emmonsia crescens is known as an environmental pathogen causing adiaspiromycosis in small rodents. As the generic name Emmonsia is no longer available for this species, its taxonomic position is re-evaluated. The intraspecific variation of Emmonsia crescens was analyzed using molecular, morphological, and physiological data, and the relationship between frequency of adiaspiromycosis and body temperature of host animals was explored. A North American and a pan-global lineage could be discerned, each with subclusters at low genetic distance. European strains produced the classical type of very large adiaspores, while in the North American lineage adiaspores relatively small, resembling the broad-based budding cells of Blastomyces. Members of the closely related genus Emergomyces may exhibit large, broad-based in addition to small, narrow-based budding cells. We conclude that the morphology of the pathogenic phase in these fungi differs gradationally between species and even populations, and is therefore less suitable as a diagnostic criterion for generic delimitation. Two Emmonsia species are reclassified in Emergomyces.


Assuntos
Temperatura Corporal , Chrysosporium , Pneumopatias Fúngicas , Animais , Chrysosporium/classificação , Chrysosporium/patogenicidade , Pneumopatias Fúngicas/veterinária
2.
J Clin Microbiol ; 56(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29070656

RESUMO

Magnusiomyces capitatus and Saprochaete clavata are members of the clade of arthroconidial yeasts that represent emerging opportunistic pulmonary pathogens in immunocompromised patients. Given that standard ribosomal DNA (rDNA) identification often provides confusing results, in this study, we analyzed 34 isolates with the goal of finding new genetic markers for classification using multilocus sequencing and amplified fragment length polymorphism (AFLP). The interspecific similarity obtained using rDNA markers (the internal transcribed spacer [ITS] and large subunit regions) was in the range of 96 to 99%, whereas that obtained using protein-coding loci (Rbp2, Act, and Tef1α) was lower at 89.4 to 95.2%. Ultimately, Rbp2 was selected as the best marker for species distinction. On the basis of cloned ITS data, some strains proved to be misidentified in comparison with the identities obtained with phenotypic characters, protein sequences, and AFLP profiles, indicating that different copies of the ribosomal operon were present in a single species. Antifungal susceptibility testing revealed that voriconazole had the lowest MIC against M. capitatus, while amphotericin B had the lowest MIC against S. clavata Both species exhibited in vitro resistance to fluconazole and micafungin.


Assuntos
Pneumopatias Fúngicas/diagnóstico , Patologia Molecular/métodos , Saccharomycetales/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/métodos , Antifúngicos/farmacologia , Proteínas de Bactérias/genética , Análise por Conglomerados , DNA Fúngico/genética , DNA Ribossômico/genética , Farmacorresistência Bacteriana , Marcadores Genéticos/genética , Humanos , Pneumopatias Fúngicas/microbiologia , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Saccharomycetales/efeitos dos fármacos , Saccharomycetales/fisiologia , Especificidade da Espécie
3.
Microb Pathog ; 125: 43-47, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30194974

RESUMO

Chromoblastomycosis is one of the most prevalent implantation fungal infections caused by melanized fungi, affecting individuals with certain risk factors with high morbidity due to its recalcitrant nature. It is difficult to identify the etiological agents and thus a suitable reproductive molecular identification method applicable in developing countries has been investigated. We report the identification of four different fungal causative agents of chromoblastomycosis by reverse line blotting hybridization (RLB) based on biotin-labeled PCR products and amine labeled probes to hybridize. Sixty five reference strains, including type strains, i.e. Fonsecaea pedrosoi, F. monophora, F. nubica, and Phialophora verrucosa, obtained from the CBS-KNAW were included in this study. Internal transcribed spacer 1 (ITS1) regions of relevant species were aligned and adjusted using BIONUMERICS v. 4.61 in order to design four specific probes to identify informative nucleotide polymorphisms. The final identification of these species by RLB assay was concordant with ITS sequencing and showed 100% specificity with no cross hybridization, able to identify all tested strains. The time and cost were less compare to other routine identification methods such as sequencing. This assay allows sensitive and specific simultaneous detection and identification of a different fungal species.


Assuntos
Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Cromoblastomicose/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Hibridização de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase/métodos , Ascomicetos/genética , Cromoblastomicose/microbiologia , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Humanos , Sondas de Oligonucleotídeos/genética , Sensibilidade e Especificidade , Análise de Sequência de DNA
4.
Med Mycol ; 56(6): 695-702, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29228273

RESUMO

Detection of species of Exophiala and Scedosporium in the respiratory tracts of cystic fibrosis (CF) patients remains controversial because of highly variable results. The results of our study suggested a significantly higher prevalence and more complex colonization than previously estimated. Approximately 17% (27/162) of clinical sputum samples were found to be positive for Exophiala dermatitidis and 30% (49/162) were positive for Scedosporium apiospermum / S. boydii species complex determined by reverse line blot (RLB) hybridization. In contrast, only 14.2% (23/162) and 1.2% (2/162) of clinical sputa were positive for E. dermatitidis and S. apiospermum / S. boydii species complex when tested by culture, respectively. Molecular detection methods, such as loop-mediated isothermal amplification (LAMP) or reverse line blot (RLB) hybridization, have the potential to become powerful alternatives to selective culture, providing a more realistic understanding on the prevalence of E. dermatitidis and S. apiospermum / S. boydii species complex in the respiratory tract of CF patients.


Assuntos
Fibrose Cística/complicações , Exophiala/isolamento & purificação , Micoses/complicações , Micoses/diagnóstico , Scedosporium/isolamento & purificação , Escarro/microbiologia , Exophiala/genética , Humanos , Técnicas de Amplificação de Ácido Nucleico , Reprodutibilidade dos Testes , Sistema Respiratório/microbiologia , Scedosporium/genética , Sensibilidade e Especificidade , Tubulina (Proteína)/genética
5.
Mycoses ; 60(6): 358-365, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28111800

RESUMO

The opportunistic black yeast are particularly known through the genus Exophiala, characterised by annellidic budding cells. However, this phenotype is polyphyletic within the order Chaetothyriales. Seventeen generic names are available in the family Herpotrichiellaceae, one of which is Exophiala. Future taxonomy will be based on molecular phylogeny; each multi-species clade may qualify for one of these names. This paper focuses on the genus Nadsoniella, which is the oldest valid name in the Herpotrichiellaceae. Despite its exophiala-like phenotype, the type species of Nadsoniella clusters in the jeanselmei-clade, competing with the sympodial genus Rhinocladiella. In contrast, Exophiala competes with morphologically pronounced genera Thysanorea and Veronaea. Replacing the current phenotypic system for phylogenetic nomenclature requires highly stable phylogenies, which currently are not available.


Assuntos
Exophiala/classificação , Filogenia , DNA Fúngico/genética , Exophiala/genética , Exophiala/isolamento & purificação , Humanos , Fungos Mitospóricos/classificação , Fungos Mitospóricos/genética , Fungos Mitospóricos/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico , Alinhamento de Sequência , Análise de Sequência de DNA
6.
Antimicrob Agents Chemother ; 60(4): 2346-51, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26833164

RESUMO

Primary central nervous system phaeohyphomycosis is a fatal fungal infection due mainly to the neurotropic melanized fungiCladophialophora bantiana,Rhinocladiella mackenziei, andExophiala dermatitidis.Despite the combination of surgery with antifungal treatment, the prognosis continues to be poor, with mortality rates ranging from 50 to 70%. Therefore, a search for a more-appropriate therapeutic approach is urgently needed. Ourin vitrostudies showed that with the combination of amphotericin B and flucytosine against these species, the median fractional inhibitory concentration (FIC) indices for strains ranged from 0.25 to 0.38, indicating synergy. By use of Bliss independence analysis, a significant degree of synergy was confirmed for all strains, with the sum ΔE ranging from 90.2 to 698.61%. No antagonism was observed. These results indicate that amphotericin B, in combination with flucytosine, may have a role in the treatment of primary cerebral infections caused by melanized fungi belonging to the orderChaetothyriales Furtherin vivostudies and clinical investigations to elucidate and confirm these observations are warranted.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Exophiala/efeitos dos fármacos , Flucitosina/farmacologia , Saccharomycetales/efeitos dos fármacos , Feoifomicose Cerebral/microbiologia , Feoifomicose Cerebral/patologia , Meios de Cultura/química , Combinação de Medicamentos , Sinergismo Farmacológico , Exophiala/crescimento & desenvolvimento , Exophiala/isolamento & purificação , Exophiala/patogenicidade , Análise Fatorial , Humanos , Testes de Sensibilidade Microbiana , Saccharomycetales/crescimento & desenvolvimento , Saccharomycetales/isolamento & purificação , Saccharomycetales/patogenicidade
7.
Med Mycol ; 53(2): 99-106, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25431472

RESUMO

Mucormycosis caused, in part, by representatives of the genus Cunninghamella is a severe infection with high mortality in patients with impaired immunity. Several species have been described in the literature as etiologic agents. A DNA barcoding study using ITS rDNA and tef-1α provided concordance of molecular data with conventional characters. The currently accepted Cunninghamella species were well supported in phylogenetic trees of both markers except for C. septata with ITS that clustered in the C. echinulata clade. Sequence variability was distinctly higher for the ITS than for tef-1α. Intraspecific ITS variability of some of the species exceeded that between some closely related species, but the marker remained applicable for species identification. The most variable species for both markers was C. echinulata. Cunninghamella bertholletiae is the main pathogenic species; infections by C. blakesleeana, C. echinulata, and C. elegans are highly exceptional.


Assuntos
Cunninghamella/classificação , Cunninghamella/genética , Código de Barras de DNA Taxonômico , Análise por Conglomerados , Cunninghamella/isolamento & purificação , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Humanos , Dados de Sequência Molecular , Mucormicose/microbiologia , Fator 1 de Elongação de Peptídeos/genética , Filogenia , Análise de Sequência de DNA
8.
Mycopathologia ; 180(1-2): 7-17, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26093392

RESUMO

Ochroconis bacilliformis, O. phaeophora and O. robusta, three novel species of the melanized genus Ochroconis (Sympoventuriaceae, Venturiales), are described, illustrated and distinguished phenotypically and molecularly from previously described species in the genus Ochroconis. Their potential significance for infection of cold-blooded vertebrates is discussed.


Assuntos
Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Micoses/microbiologia , Micoses/veterinária , Animais , Ascomicetos/citologia , Ascomicetos/genética , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Genes de RNAr , Técnicas Microbiológicas , Microscopia , Dados de Sequência Molecular , Filogenia , RNA Fúngico/genética , RNA Ribossômico/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Vertebrados
9.
Antimicrob Agents Chemother ; 58(10): 5877-85, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25070092

RESUMO

Scedosporium species show decreased susceptibility to the majority of systemic antifungal drugs. Acquired resistance is likely to disseminate differentially with the mode of exchange of genetic material between lineages. Inter- and intraspecific diversities of Scedosporium species were analyzed for three partitions (rDNA internal transcribed spacer gene [ITS], partial ß-tubulin gene, and amplified fragment length polymorphism profiles), with the aim to establish distribution of resistance between species, populations, and strains. Heterogeneity of and recombination between lineages were determined, and distances between clusters were calculated using a centroid approach. Clinical, geographic, and antifungal data were plotted on diversity networks. Scedosporium minutisporum, Scedosporium desertorum, and Scedosporium aurantiacum were distinguished unambiguously in all partitions and had differential antifungal susceptibility profiles (ASP). Pseudallescheria fusoidea and Pseudallescheria ellipsoidea were indistinguishable from Scedosporium boydii. Pseudallescheria angusta took an intermediate position between Scedosporium apiospermum and S. boydii. Scedosporium boydii and S. apiospermum had identical ASP. Differences in (multi)resistance were linked to individual strains. S. apiospermum and S. boydii showed limited interbreeding and were recognized as valid, sympatric species. The S. apiospermum/S. boydii group, comprising the main clinically relevant Scedosporium species, consists of separate lineages and is interpreted as a complex undergoing sympatric evolution with incomplete lineage sorting. In routine diagnostics, the lineages in S. apiospermum/S. boydii are indicated with the umbrella descriptor "S. apiospermum complex"; individual species can be identified with rDNA ITS with 96.3% confidence. Voriconazole is recommended as the first-line treatment; resistance against this compound is rare.


Assuntos
Antifúngicos/farmacologia , Scedosporium/efeitos dos fármacos , Pseudallescheria/efeitos dos fármacos , Voriconazol/farmacologia
10.
J Clin Microbiol ; 51(3): 931-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23303502

RESUMO

The species diversity and identification of black fungi belonging to Cyphellophora and Phialophora, which colonize and infect human skin and nails, were studied using amplified fragment length polymorphism (AFLP). A total of 76 Cyphellophora and Phialophora isolates were evaluated, and their delimitation was compared to earlier studies using multilocus sequencing. The results of the AFLP analysis and sequencing were in complete agreement with each other. Seven species-specific padlock probes for the most prevalent species were designed on the basis of the ribosomal DNA internal transcribed spacer region, and identification of the respective species could easily be achieved with the aid of rolling circle amplification.


Assuntos
Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/métodos , Ascomicetos/classificação , Ascomicetos/genética , Tipagem Molecular/métodos , Técnicas de Tipagem Micológica/métodos , Phialophora/classificação , Phialophora/genética , Ascomicetos/isolamento & purificação , Primers do DNA/genética , DNA Espaçador Ribossômico/genética , Phialophora/isolamento & purificação
11.
Persoonia ; 30: 48-56, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24027346

RESUMO

Mucormycosis usually presents as a progressive infection with significant angio-invasion. Mucormycosis due to Mucor irregularis (formerly Rhizomucor variabilis var. variabilis), however, is exceptional in causing chronic cutaneous infection in immunocompetent humans, ultimately leading to severe morbidity if left untreated. More than 90 % of the cases known to date were reported from Asia, mainly from China. The nearest neighbour of M. irregularis is the saprobic species M. hiemalis. The aim of this study was to evaluate the taxonomic position, epidemiology, and intra- and inter-species diversity of M. irregularis based on 21 strains (clinical n = 17) by multilocus analysis using ITS, LSU, RPB1 and RPB2 genes, compared to results of cluster analysis with amplified fragment length polymorphism (AFLP) data. By combining MLST and AFLP analyses, M. irregularis was found to be monophyletic with high bootstrap support, and consisted of five subgroups, which were not concordant in all partitions. It was thus confirmed that M. irregularis is a single species at 96.1-100 % ITS similarity and low recombination rates between populations. Some geographic structuring was noted with some localised populations, which may be explained by limited air-dispersal. The natural habitat of the species is likely to be in soil and decomposing plant material.

12.
J Clin Microbiol ; 50(9): 2987-94, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22760037

RESUMO

The first yellow-grain fungal mycetoma, in a 60-year-old man from Central Sudan, is reported. Morphological and phylogenetic analysis of the ribosomal small subunit (SSU), large subunit (LSU), internal transcribed spacer (ITS), ß-tubulin (BT2), actin (ACT1), and elongation factor (TEF1) genes revealed that the isolate deviated from any known agent of mycetoma; it clustered in the genus Pleurostoma (anamorph genus, Pleurostomophora) in the order Calosphaeriales. The novel species, here named Pleurostomophora ochracea, is characterized by phenotypic features. The species proved to be highly susceptible to itraconazole, ketoconazole, posaconazole, and voriconazole, but not to fluconazole. The fungus was inhibited by caspofungin at 8 µg/ml, while no inhibition was found with 5-flucytosine (MIC > 64 µg/ml). Compared to other members of the genus Pleurostomophora, P. ochracea is slow growing, with a relatively high optimum growth temperature (36 to 37°C). This is the first case of a yellow-grain fungal mycetoma; yellow grains are otherwise of bacterial nature. Our case emphasizes that identification of mycetoma agents by the color of the grain only is not sufficient and may lead to inappropriate therapy.


Assuntos
Ascomicetos/isolamento & purificação , Micetoma/microbiologia , Micetoma/patologia , Antifúngicos/farmacologia , Ascomicetos/citologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Proteínas Fúngicas/genética , Genes de RNAr , Humanos , Masculino , Testes de Sensibilidade Microbiana , Microscopia , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , RNA Fúngico/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Sudão , Temperatura
13.
Emerg Infect Dis ; 17(3): 464-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21392438

RESUMO

To assess population diversities among 81 strains of fungi in the genus Fonsecaea that had been identified down to species level, we applied amplified fragment-length polymorphism (AFLP) technology and sequenced the internal transcribed spacer regions and the partial cell division cycle, beta-tubulin, and actin genes. Many species of the genus Fonsecaea cause human chromoblastomycosis. Strains originated from a global sampling of clinical and environmental sources in the Western Hemisphere, Asia, Africa, and Europe. According to AFLP fingerprinting, Fonsecaea isolates clustered in 5 groups corresponding with F. pedrosoi, F. monophora, and F. nubica: the latter 2 species each comprised 2 groups, and F. pedrosoi appeared to be of monophyletic origin. F. pedrosoi was found nearly exclusively in Central and South America. F. monophora and F. nubica were distributed worldwide, but both showed substantial geographic structuring. Clinical cases outside areas where Fonsecaea is endemic were probably distributed by human migration.


Assuntos
Ascomicetos/genética , Cromoblastomicose/epidemiologia , Epidemiologia Molecular , Actinas/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Cromoblastomicose/microbiologia , DNA Fúngico/análise , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Microbiologia Ambiental , Feminino , Saúde Global , Humanos , Masculino , Técnicas de Tipagem Micológica , Especificidade da Espécie , Tubulina (Proteína)/genética
14.
J Clin Microbiol ; 49(3): 960-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21177887

RESUMO

The major clinically relevant species in Scedosporium (teleomorph Pseudallescheria) are Pseudallescheria boydii, Scedosporium aurantiacum, Scedosporium apiospermum, and Scedosporium prolificans, while Pseudallescheria minutispora, Petriellopsis desertorum, and Scedosporium dehoogii are exceptional agents of disease. Three molecular methods targeting the partial ß-tubulin gene were developed and evaluated to identify six closely related species of the S. apiospermum complex using quantitative real-time PCR (qPCR), PCR-based reverse line blot (PCR-RLB), and loop-mediated isothermal amplification (LAMP). qPCR was not specific enough for the identification of all species but had the highest sensitivity. The PCR-RLB assay was efficient for the identification of five species. LAMP distinguished all six species unambiguously. The analytical sensitivities of qPCR, PCR-RLB, and LAMP combined with MagNAPure, CTAB (cetyltrimethylammonium bromide), and FTA filter (Whatman) extraction were 50, 5 × 10(3), and 5 × 10(2) cells/µl, respectively. When LAMP was combined with a simplified DNA extraction method using an FTA filter, identification to the species level was achieved within 2 h, including DNA extraction. The FTA-LAMP assay is therefore recommended as a cost-effective, simple, and rapid method for the identification of Scedosporium species.


Assuntos
Técnicas de Diagnóstico Molecular/métodos , Micetoma/diagnóstico , Micetoma/microbiologia , Micologia/métodos , Pseudallescheria/isolamento & purificação , Scedosporium/isolamento & purificação , Proteínas Fúngicas/genética , Humanos , Técnicas de Amplificação de Ácido Nucleico/métodos , Pseudallescheria/genética , Scedosporium/genética , Sensibilidade e Especificidade , Tubulina (Proteína)/genética
15.
Fungal Biol ; 121(5): 488-500, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28390506

RESUMO

The present study assessed the diversity of black yeast-like fungi present on babassu coconut shells, a substrate rich in lipids and several volatile organic compounds (VOCs) including aromatic hydrocarbons. Using different isolation methods, one-hundred-six isolates were obtained and were identified by ITS sequencing as members of the genera Exophiala, Cladophialophora, Veronaea, and Rhinocladiella. Two novel species were discovered. Eight strains were selected for assessing their ability to grow on toluene and phenyl acetate as the sole carbon and energy source. All strains tested were able to assimilate phenyl acetate, while two out of eight were able to use toluene. VOCs profiling in babassu samples was also investigated by GC-ToF MS, revealing that a complex mixture of VOCs was emitted, which included alkylbenzenes such as toluene. Assimilation of alkylbenzenes by the black yeasts might therefore be the result of evolutionary adaptation to symbiotic interactions with higher plants. The potential relationship between lipid/aromatic hydrocarbon metabolism and pathogenicity is also discussed.


Assuntos
Cocos/microbiologia , Fungos/classificação , Fungos/isolamento & purificação , Composição de Bases , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Ésteres/análise , Fungos/metabolismo , Filogenia , Análise de Sequência de DNA , Compostos Orgânicos Voláteis/análise
16.
Fungal Biol ; 120(2): 137-46, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26781369

RESUMO

The genus Scedosporium currently comprises six species, Scedosporium apiospermum, Scedosporium boydii, Pseudallescheria angusta, Scedosporium minutisporum, Scedosporium dehoogii, and Scedosporium aurantiacum, most of which can be distinguished with the primary fungal DNA barcode, the ITS1/2 region of the rDNA gene cluster. In the present study, four additional genetic loci were explored from a phylogenetic point of view enabling a barcoding approach based on K2P pairwise distances to resolve the taxa Scedosporium. We included partial γ-actin (ACT), ß-tubulin (BT2), elongation factor 1α (TEF1), and the small ribosomal protein 60S L10 (L1) (RP60S). Phylogenetic inference of each marker individually showed that four out of six species within Scedosporium can be distinguished unambiguously, while strains of S. apiospermum, S. boydii, and P. angusta showed occasional recombination, and accordingly, no genealogical concordance between markers was obtainable. We defined S. apiospermum, S. boydii, and P. angusta as the 'S. apiospermum species complex' since observed differences were not consistent between lineages, and no clinical differences are known between entities within the complex. While BT2 revealed the best performance among the genetic loci tested at the lineage level, barcoding of the ITS region is sufficient for distinction of all entities in Scedosporium at the species or 'complex' level.


Assuntos
Micoses/microbiologia , Scedosporium/isolamento & purificação , Actinas/genética , Proteínas Fúngicas/genética , Humanos , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , Filogenia , Scedosporium/classificação , Scedosporium/genética , Tubulina (Proteína)/genética
17.
PLoS Negl Trop Dis ; 9(10): e0004004, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26496430

RESUMO

Global distribution patterns of Cladophialophora carrionii, agent of human chromoblastomycosis in arid climates of Africa, Asia, Australia, Central-and South-America, were compared with similar data of the vicarious Fonsecaea spp., agents of the disease in tropical rain forests. Population diversities among 73 C. carrionii strains and 60 strains of three Fonsecaea species were analyzed for rDNA ITS, partial ß-tubulin, and amplified fragment-length polymorphism (AFLP) fingerprints. Populations differed significantly between continents. Lowest haplotype diversity was found in South American populations, while African strains were the most diverse. Gene flow was noted between the African population and all other continents. The general pattern of Fonsecaea agents of chromoblastomycosis differed significantly from that of C. carrionii and revealed deeper divergence among three differentiated species with smaller numbers of haplotypes, indicating a longer evolutionary history.


Assuntos
Ascomicetos/isolamento & purificação , Cromoblastomicose/epidemiologia , Variação Genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Ascomicetos/classificação , Ascomicetos/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Clima Desértico , Fluxo Gênico , Genótipo , Saúde Global , Haplótipos , Humanos , Clima Tropical , Tubulina (Proteína)/genética
18.
Fungal Biol ; 115(10): 1051-65, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21944217

RESUMO

Distribution of populations of the opportunistic black yeast Exophiala dermatitidis was studied using AFLP. This fungus has been hypothesized to have a natural habitat in association with frugivorous birds and bats in the tropical rain forest, and to emerge in the human-dominated environment, where it occasionally causes human pulmonary or fatal disseminated and neurotropic disease. The hypothesis of its natural niche was investigated by comparing a set of 178 strains from natural and human-dominated environments in Thailand with a worldwide selection of 107 strains from the reference collection of the CBS Fungal Biodiversity Centre, comprising 75.7% clinical isolates. Many isolates had unique AFLP patterns and were too remote for confident comparison. Eight populations containing multiple isolates could be distinguished, enabling determination of geographic distributions of these populations. Some of the populations were confined to Thailand, while others occurred worldwide. The local populations from Thailand contained strains from natural and urban environments, suggesting an environmental jump of the fungus. Strains from human brain belonged to widely dispersed populations. In some cases cerebral isolates were identical to isolates from the human intestinal tract. The possibility of cerebral infection through intestinal translocation was thus not excluded.


Assuntos
Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Exophiala/genética , Exophiala/isolamento & purificação , Frutas/microbiologia , Feoifomicose/microbiologia , Feoifomicose/veterinária , Animais , Microbiologia Ambiental , Exophiala/classificação , Exophiala/fisiologia , Humanos , Feoifomicose/transmissão , Filogenia , Tailândia
19.
J Microbiol Methods ; 80(2): 138-42, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19961882

RESUMO

A simple method for fungal genotype screening was developed for the black yeast Exophiala dermatitidis based on RFLP of ribosomal ITS regions currently used as potential virulence markers. In a study set of 502 strains of the species, two main genotypes were recognized. Only 0.97% of lanes were difficult to interpret as they did not clearly present one of the expected genotypes. Twenty strains were deviating and proved to be E. spinifera after sequencing. Eight common, related species (based on SSU data) with clinical significance yielded different patterns with TaqI digestion, and thus the method is also usable for routine diagnostics.


Assuntos
Exophiala/genética , Exophiala/patogenicidade , Técnicas de Tipagem Micológica/métodos , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Exophiala/classificação , Genótipo , Sensibilidade e Especificidade , Virulência
20.
Med Mycol ; 47(1): 51-62, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18720218

RESUMO

While many members of the black yeasts genus Cladophialophora have been reported to cause diseases in humans, understanding of their natural niche is frequently lacking. Some species can be recovered from the natural environment by means of selective isolation techniques. The present study focuses on a Cladophialophora strain that caused an interdigital tinea nigra-like lesion in a HIV-positive Brazilian child. The fungal infection was successfully treated with oxiconazole. Similar strains had been recovered from the environment in Brazil, Uruguay and the Netherlands. The strains were characterized by sequencing the Internal Transcribed Spacer (ITS) regions and the small subunit (SSU) of the nuclear ribosomal RNA gene, as well as the elongation factor 1-alpha (EF1alpha) gene. Since no match with any known species was found, it is described as the new species, Cladophialophora saturnica.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Ascomicetos/classificação , Ascomicetos/genética , Dermatomicoses/microbiologia , Infecções por HIV/complicações , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Antifúngicos/uso terapêutico , Ascomicetos/isolamento & purificação , Brasil , Pré-Escolar , DNA Fúngico/análise , Dermatomicoses/tratamento farmacológico , Feminino , Humanos , Imidazóis/uso terapêutico , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie , Resultado do Tratamento
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