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Ralf Bialek - One of the best experts on this subject based on the ideXlab platform.
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pcr assays for identification of coccidioides posadasii based on the nucleotide sequence of the antigen 2 proline rich antigen
Journal of Clinical Microbiology, 2004Co-Authors: Ralf Bialek, Tanja Herrmann, Jan Kern, Rolando Tijerina, Luis A Cecenas, Udo Reischl, Gloria M GonzalezAbstract:A conventional nested PCR and a real-time LightCycler PCR assay for detection of Coccidioides posadasii DNA were designed and tested in 120 clinical strains. These had been isolated from 114 patients within 10 years in Monterrey, Nuevo Leon, Mexico, known to be endemic for coccidioidomycosis. The gene encoding the specific antigen 2/proline-rich antigen (Ag2/PRA) was used as a target. All strains were correctly identified, whereas DNA from related members of the family Onygenaceae remained negative. Melting curve analysis by LightCycler and sequencing of the 526-bp product of the first PCR demonstrated either 100% identity to the GenBank sequence of the Silveira strain, now known to be C. posadasii (accession number AF013256), or a single silent mutation at position 1228. Length determination of two microsatellite-containing loci (GAC and 621) identified all 120 isolates as C. posadasii. Specific DNA was amplified by conventional nested PCR from three microscopically spherule-positive paraffin-embedded tissue samples, whereas 20 human tissue samples positive for other dimorphic fungi remained negative. Additionally, the safety of each step of a modified commercially available DNA extraction procedure was evaluated by using 10 strains. At least three steps of the protocol were demonstrated to sufficiently kill arthroconidia. This safe procedure is applicable to cultures and to clinical specimens.
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nested pcr assays for detection of blastomyces dermatitidis dna in paraffin embedded canine tissue
Journal of Clinical Microbiology, 2003Co-Authors: Ralf Bialek, Anna Cascante Cirera, Tanja Herrmann, Christian Aepinus, Valerie Shearnbochsler, Alfred M. LegendreAbstract:A Blastomyces dermatitidis nested PCR assay targeting the gene encoding the Wisconsin 1 (WI-1) adhesin was developed and compared with a nested PCR targeting the 18S rRNA gene (rDNA) of members of the family Onygenaceae. We examined 73 paraffin-embedded tissue samples obtained from nine dogs which died of blastomycosis and nine dogs which succumbed to lymphosarcoma according to autopsy findings; amplifiable canine DNA was extracted from 25 and 33 specimens from the two groups, respectively. The B. dermatitidis PCR amplified DNA from 8 of 13 tissue samples in which yeast cells were detected by microscopy. Sequencing revealed that all PCR products were homologous to the B. dermatitidis WI-1 adhesin gene. No PCR product was amplified from 12 microscopically negative biopsy specimens from dogs with blastomycosis or from 33 biopsy specimens from dogs with lymphosarcoma. The 18S rDNA PCR amplified DNA from 10 and 9 tissue samples taken from dogs which died of blastomycosis and lymphosarcoma, respectively. Only six products were identified as being identical to B. dermatitidis 18S rDNA; they were exclusively obtained from specimens positive by the B. dermatitidis nested PCR. For specificity testing, 20 human biopsy specimens proven to have histoplasmosis were examined, and a specific H. capsulatum product was amplified by the 18S rDNA PCR from all specimens, whereas no product was obtained from any of the 20 samples by the B. dermatitidis PCR assay. In conclusion, the PCR targeting a gene encoding the unique WI-1 adhesin is as sensitive as but more specific than the PCR targeting the 18S rDNA for detection of B. dermatitidis in canine tissue.
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Small subunit ribosomal DNA sequence shows Paracoccidioides brasiliensis closely related to Blastomyces dermatitidis
Journal of Clinical Microbiology, 2000Co-Authors: Ralf Bialek, Aida Ibricevic, Annette W. Fothergill, Dominik BegerowAbstract:The similarities of paracoccidioidomycosis and blastomycosis are highly suggestive of a close relation of the two etiological agents. Whereas the agent of the first disease is exclusively endemic in Latin America, the agent of the latter one is endemic in North America and Africa. In symptomatic travelers visiting both areas of endemicity, differentiation of the diseases might be impossible, even though therapy and prognosis for these two diseases differ significantly. In order to identify differences in the 18S rRNA gene (rDNA) for use as molecular diagnostic tools, we sequenced this gene from five isolates of Paracoccidioides brasiliensis and compared them to known sequences of other fungi. Neighbor-joining, maximum parsimony, and maximum likelihood analyses and, finally, the Kishino-Hasegawa test revealed that P. brasiliensis, Blastomyces dermatitidis, and Emmonsia parva are more closely related than Histoplasma capsulatum and B. dermatitidis, whose teleomorphic forms belong to one genus, Ajellomyces. In accordance with the work of other investigators who have used internal transcribed spacer and large subunit rDNA sequences, our small subunit rDNA data show that the dimorphic fungus P. brasiliensis must be grouped within the order Onygenales and is closely related to members of the family Onygenaceae. There are hints in the molecular phylogenetic analysis that the family Onygenaceae might be further divided into two families. The subgroup that includes P. brasiliensis comprises all zoopathogenic species. The differences in the 18S rDNAs appear to be too small to allow species identification of the members of the family Onygenaceae pathogenic for humans by use of target sequences within this gene.
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Small Subunit Ribosomal DNA Sequence Shows Paracoccidioides brasiliensis Closely Related to
2000Co-Authors: Blastomyces Dermatitidis, Aida Ibricevic, Ralf Bialek, Annette W. Fothergill, Dominik BegerowAbstract:The similarities of paracoccidioidomycosis and blastomycosis are highly suggestive of a close relation of the two etiological agents. Whereas the agent of the first disease is exclusively endemic in Latin America, the agent of the latter one is endemic in North America and Africa. In symptomatic travelers visiting both areas of endemicity, differentiation of the diseases might be impossible, even though therapy and prognosis for these two diseases differ significantly. In order to identify differences in the 18S rRNA gene (rDNA) for use as molecular diagnostic tools, we sequenced this gene from five isolates of Paracoccidioides brasiliensis and compared them to known sequences of other fungi. Neighbor-joining, maximum parsimony, and maximum likelihood analyses and, finally, the Kishino-Hasegawa test revealed that P. brasiliensis, Blastomyces dermatitidis, and Emmonsia parva are more closely related than Histoplasma capsulatum and B. dermatitidis, whose teleomorphic forms belong to one genus, Ajellomyces. In accordance with the work of other investigators who have used internal transcribed spacer and large subunit rDNA sequences, our small subunit rDNA data show that the dimorphic fungus P. brasiliensis must be grouped within the order Onygenales and is closely related to members of the family Onygenaceae. There are hints in the molecular phylogenetic analysis that the family Onygenaceae might be further divided into two families. The subgroup that includes P. brasiliensis comprises all zoopathogenic species. The differences in the 18S rDNAs appear to be too small to allow species identificatio
Lynne Sigler - One of the best experts on this subject based on the ideXlab platform.
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molecular characterization of reptile pathogens currently known as members of the chrysosporium anamorph of nannizziopsis vriesii complex and relationship with some human associated isolates
Journal of Clinical Microbiology, 2013Co-Authors: Lynne Sigler, Sarah Hambleton, Jean A PareAbstract:ABSTRACT In recent years, the Chrysosporium anamorph of Nannizziopsis vriesii (CANV), Chrysosporium guarroi, Chrysosporium ophiodiicola, and Chrysosporium species have been reported as the causes of dermal or deep lesions in reptiles. These infections are contagious and often fatal and affect both captive and wild animals. Forty-nine CANV isolates from reptiles and six isolates from human sources were compared with N. vriesii based on their cultural characteristics and DNA sequence data. Analyses of the sequences of the internal transcribed spacer and small subunit of the nuclear ribosomal gene revealed that the reptile pathogens and human isolates belong in well-supported clades corresponding to three lineages that are distinct from all other taxa within the family Onygenaceae of the order Onygenales. One lineage represents the genus Nannizziopsis and comprises N. vriesii, N. guarroi, and six additional species encompassing isolates from chameleons and geckos, crocodiles, agamid and iguanid lizards, and humans. Two other lineages comprise the genus Ophidiomyces, with the species Ophidiomyces ophiodiicola occurring only in snakes, and Paranannizziopsis gen. nov., with three new species infecting squamates and tuataras. The newly described species are Nannizziopsis dermatitidis, Nannizziopsis crocodili, Nannizziopsis barbata, Nannizziopsis infrequens, Nannizziopsis hominis, Nannizziopsis obscura, Paranannizziopsis australasiensis, Paranannizziopsis californiensis, and Paranannizziopsis crustacea. Chrysosporium longisporum has been reclassified as Paranannizziopsis longispora. N. guarroi causes yellow fungus disease, a common infection in bearded dragons and green iguanas, and O. ophiodiicola is an emerging pathogen of captive and wild snakes. Human-associated species were not recovered from reptiles, and reptile-associated species were recovered only from reptiles, thereby mitigating concerns related to zoonosis.
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disseminated infection due to chrysosporium zonatum in a patient with chronic granulomatous disease and review of non aspergillus fungal infections in patients with this disease
Journal of Clinical Microbiology, 1999Co-Authors: Emmanuel Roilides, Lynne Sigler, Evangelia Bibashi, Helen Katsifa, Nicolas Flaris, Christos P PanteliadisAbstract:We report the first case of Chrysosporium zonatum infection in a 15-year-old male with chronic granulomatous disease who developed a lobar pneumonia and tibia osteomyelitis while on prophylaxis with gamma interferon. The fungus was isolated from sputum and affected bone, and hyphae were observed in the bone by histopathology. Therapy with amphotericin B eradicated the osteomyelitis and pneumonia, but pneumonia recurred in association with pericarditis and pleuritis during therapy with itraconazole. These manifestations subsided, and no recurrences occurred with liposomal amphotericin B therapy. Infections caused by Chrysosporium species are very rare, and C. zonatum has not previously been reported to cause mycosis in humans. This species, the anamorph of the heterothallic ascomycete Uncinocarpus orissi (family Onygenaceae), is distinguished by its thermotolerance, by colonies which darken from yellowish white to buff, and by club-shaped terminal aleurioconidia borne at the ends of short, typically curved stalks. The case isolate produced fertile ascomata in mating tests with representative isolates. The median (range) MICs for our isolate as well as those for two other human isolates and a nonhuman isolate determined by the National Committee for Clinical Laboratory Standards method adapted for moulds were ≤0.06 μg/ml (≤0.06 to 0.25 μg/ml) for amphotericin B, 0.687 μg/ml (0.25 to 2 μg/ml) for itraconazole, >128 μg/ml (>128 μg/ml) for flucytosine, and 48 μg/ml (32 to >128 μg/ml) for fluconazole.
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molecular genetic variation in emmonsia crescens and emmonsia parva etiologic agents of adiaspiromycosis and their phylogenetic relationship to blastomyces dermatitidis ajellomyces dermatitidis and other systemic fungal pathogens
Journal of Clinical Microbiology, 1998Co-Authors: Stephen W Peterson, Lynne SiglerAbstract:Emmonsia crescens, an agent of adiaspiromycosis, Blastomyces dermatitidis, the agent of blastomycosis, and Histoplasma capsulatum, the agent of histoplasmosis, are known to form meiotic (sexual) stages in the ascomycete genus Ajellomyces (Onygenaceae, Onygenales), but no sexual stage is known for E. parva, the type species of the genus Emmonsia. To evaluate relationships among members of the putative Ajellomyces clade, large-subunit ribosomal and internal transcribed spacer region DNA sequences were determined from PCR-amplified DNA fragments. Sequences were analyzed phylogenetically to evaluate the genetic variation within the genus Emmonsia and evolutionary relationships to other taxa. E. crescens and E. parva are distinct species. E. crescens isolates are placed into two groups that correlate with their continents of origin. Considerable variation occurred among isolates previously classified as E. parva. Most isolates are placed into two closely related groups, but the remaining isolates, including some from human sources, are phylogenetically distinct and represent undescribed species. Strains of B. dermatitidis are a sister species of E. parva. Paracoccidioides brasiliensis and Histoplasma capsulatum are ancestral to most Emmonsia isolates, and P. brasiliensis, which has no known teleomorph, falls within the Ajellomyces clade.
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the genus uncinocarpus Onygenaceae and its synonym brunneospora new concepts combinations and connections to anamorphs in chrysosporium and further evidence of relationship with coccidioides immitis
Botany, 1998Co-Authors: Lynne Sigler, Arlene L Flis, J W CarmichaelAbstract:The genus Uncinocarpus (Onygenales, Onygenaceae) is emended to include keratinophilic fungi with discrete, globose gymnothecial ascomata without differentiated ascomatal hyphae and bearing uncinate, helical, or no appendages; oblate, punctate ascospores sometimes with irregular reticulations; bulbous initials, and Malbranchea or Chrysosporium anamorphs. The new combination Uncinocarpus orissi is proposed for Pseudoarachniotus orissi; Gymnoascus arxii is shown to be a synonym. New records show that the fungus has a wide distribution from North America, Europe, Asia, and the Middle East. The teleomorph is formed under laboratory conditions by mating representative isolates. The anamorph has been described under the names Chrysosporium zonatum and Chrysosporium gourii. Chrysosporium queenslandicum is morphologically similar. Its teleomorph Apinisia queenslandica is transferred also to the genus Uncinocarpus as Uncinocarpus queenslandicus. Brunneospora reticulata, the type species of the genus Brunneospora, i...
Dominik Begerow - One of the best experts on this subject based on the ideXlab platform.
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Small subunit ribosomal DNA sequence shows Paracoccidioides brasiliensis closely related to Blastomyces dermatitidis
Journal of Clinical Microbiology, 2000Co-Authors: Ralf Bialek, Aida Ibricevic, Annette W. Fothergill, Dominik BegerowAbstract:The similarities of paracoccidioidomycosis and blastomycosis are highly suggestive of a close relation of the two etiological agents. Whereas the agent of the first disease is exclusively endemic in Latin America, the agent of the latter one is endemic in North America and Africa. In symptomatic travelers visiting both areas of endemicity, differentiation of the diseases might be impossible, even though therapy and prognosis for these two diseases differ significantly. In order to identify differences in the 18S rRNA gene (rDNA) for use as molecular diagnostic tools, we sequenced this gene from five isolates of Paracoccidioides brasiliensis and compared them to known sequences of other fungi. Neighbor-joining, maximum parsimony, and maximum likelihood analyses and, finally, the Kishino-Hasegawa test revealed that P. brasiliensis, Blastomyces dermatitidis, and Emmonsia parva are more closely related than Histoplasma capsulatum and B. dermatitidis, whose teleomorphic forms belong to one genus, Ajellomyces. In accordance with the work of other investigators who have used internal transcribed spacer and large subunit rDNA sequences, our small subunit rDNA data show that the dimorphic fungus P. brasiliensis must be grouped within the order Onygenales and is closely related to members of the family Onygenaceae. There are hints in the molecular phylogenetic analysis that the family Onygenaceae might be further divided into two families. The subgroup that includes P. brasiliensis comprises all zoopathogenic species. The differences in the 18S rDNAs appear to be too small to allow species identification of the members of the family Onygenaceae pathogenic for humans by use of target sequences within this gene.
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Small Subunit Ribosomal DNA Sequence Shows Paracoccidioides brasiliensis Closely Related to
2000Co-Authors: Blastomyces Dermatitidis, Aida Ibricevic, Ralf Bialek, Annette W. Fothergill, Dominik BegerowAbstract:The similarities of paracoccidioidomycosis and blastomycosis are highly suggestive of a close relation of the two etiological agents. Whereas the agent of the first disease is exclusively endemic in Latin America, the agent of the latter one is endemic in North America and Africa. In symptomatic travelers visiting both areas of endemicity, differentiation of the diseases might be impossible, even though therapy and prognosis for these two diseases differ significantly. In order to identify differences in the 18S rRNA gene (rDNA) for use as molecular diagnostic tools, we sequenced this gene from five isolates of Paracoccidioides brasiliensis and compared them to known sequences of other fungi. Neighbor-joining, maximum parsimony, and maximum likelihood analyses and, finally, the Kishino-Hasegawa test revealed that P. brasiliensis, Blastomyces dermatitidis, and Emmonsia parva are more closely related than Histoplasma capsulatum and B. dermatitidis, whose teleomorphic forms belong to one genus, Ajellomyces. In accordance with the work of other investigators who have used internal transcribed spacer and large subunit rDNA sequences, our small subunit rDNA data show that the dimorphic fungus P. brasiliensis must be grouped within the order Onygenales and is closely related to members of the family Onygenaceae. There are hints in the molecular phylogenetic analysis that the family Onygenaceae might be further divided into two families. The subgroup that includes P. brasiliensis comprises all zoopathogenic species. The differences in the 18S rDNAs appear to be too small to allow species identificatio
Ke-qin Zhang - One of the best experts on this subject based on the ideXlab platform.
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Independent expansion of zincin metalloproteinases in Onygenales fungi may be associated with their pathogenicity.
PLoS ONE, 2014Co-Authors: Ke-qin ZhangAbstract:To get a comprehensive view of fungal M35 family (deuterolysin) and M36 family (fungalysin) genes, we conducted genome-wide investigations and phylogenetic analyses of genes in these two families from 50 sequenced Ascomycota fungi with different life styles. Large variations in the number of M35 family and M36 family genes were found among different fungal genomes, indicating that these two gene families have been highly dynamic through fungal evolution. Moreover, we found obvious expansions of Meps in two families of Onygenales: Onygenaceae and Arthodermataceae, whereas species in family Ajellomycetace did not show expansion of these genes. The strikingly different gene duplication and loss patterns in Onygenales may be associated with the different pathogenicity of these species. Interestingly, likelihood ratio tests (LRT) of both M35 family and M36 family genes suggested that several branches leading to the duplicated genes in dermatophytic and Coccidioides fungi had signatures of positive selection, indicating that the duplicated Mep genes have likely diverged functionally to play important roles during the evolution of pathogenicity of dermatophytic and Coccidioides fungi. The potentially positively selected residues discovered by our analysis may have contributed to the development of new physiological functions of the duplicated Mep genes in dermatophytic fungi and Coccidioides species. Our study adds to the current knowledge of the evolution of Meps in fungi and also establishes a theoretical foundation for future experimental investigations.
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Independent Expansion of Zincin Metalloproteinases in Onygenales Fungi May Be Associated with Their
2013Co-Authors: Ke-qin ZhangAbstract:To get a comprehensive view of fungal M35 family (deuterolysin) and M36 family (fungalysin) genes, we conducted genome-wide investigations and phylogenetic analyses of genes in these two families from 50 sequenced Ascomycota fungi with different life styles. Large variations in the number of M35 family and M36 family genes were found among different fungal genomes, indicating that these two gene families have been highly dynamic through fungal evolution. Moreover, we found obvious expansions of Meps in two families of Onygenales: Onygenaceae and Arthodermataceae, whereas species in family Ajellomycetace did not show expansion of these genes. The strikingly different gene duplication and loss patterns in Onygenales may be associated with the different pathogenicity of these species. Interestingly, likelihood ratio tests (LRT) of both M35 family and M36 family genes suggested that several branches leading to the duplicated genes in dermatophytic and Coccidioides fungi had signatures of positive selection, indicating that the duplicated Mep genes have likely diverged functionally to play important roles during the evolution of pathogenicity of dermatophytic and Coccidioides fungi. The potentially positively selected residues discovered by our analysis may have contributed to the development of new physiological functions of the duplicated Mep genes in dermatophytic fungi and Coccidioides species. Our study adds to the current knowledge of the evolution of Meps in fungi and also establishes a theoretical foundation for future experimental investigations
Francesco Doveri - One of the best experts on this subject based on the ideXlab platform.
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A polyphasic contribution to the knowledge of Auxarthron (Onygenaceae)
Mycological Progress, 2015Co-Authors: Sabrina Sarrocco, Giovanni Vannacci, Stefania Diquattro, Riccardo Baroncelli, Alessio Cimmino, Antonio Evidente, Francesco DoveriAbstract:In a survey of coprophilous fungi in Italy, two interesting ascomycetes were recovered from hedgehog dung. These fungi showed a sexual morph characterized by gymnothecia, globose reticulate ascospores, a Malbranchea asexual state, and a keratinolytic ability, and were identified morphologically and molecularly as Auxarthron umbrinum and A. concentricum of the Onygenaceae. The history, ecology, and morphology of the genus Auxarthron as a whole, and of A. umbrinum and A. concentricum in particular, are revised. A preliminary evaluation of the antagonistic properties of A. umbrinum and A. concentricum against phytopathogenic fungi has been performed in dual cultures. Growth inhibition of some plant pathogenic fungi was recorded, and the effects were growth medium dependent. When solid-state fermentation (SSF) substrate of both Auxarthron isolates has been submitted to extraction, both the organic extract residues ( n -hexane and CH_2Cl_2) and the lyophilized aqueous phases were used for the antibiotic test against plant pathogenic fungi. Significant antifungal activity was obtained by organic fractions and aqueous residue of A. concentricum against Alternaria brassicicola and Botrytis cinerea , whereas A. umbrinum appeared to be less effective. The analysis of ITS nrDNA sequences suggests that an extensive phylogenetic revision of the genus Auxarthron is necessary.
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A comparative study of Neogymnomyces virgineus, a new keratinolytic species from dung, and its relationships with the Onygenales
Fungal Diversity, 2012Co-Authors: Francesco Doveri, Susanna Pecchia, Mariarosaria Vergara, Sabrina Sarrocco, Giovanni VannacciAbstract:Isolations of onygenalean fungi were made recently from different dung samples from Italy. A striking snow-white species with gymnothecial ascomata, developed in damp chamber on dormouse dung collected in a cave, was subjected to keratinolytic tests and morphological, cultural, and phylogenetic studies. The keratinolytic ability of this species, associated with a Chrysosporium anamorph and a sexual state of appendiculate reticuloperidia and oblate ascospores, allows it to be accomodated in Onygenaceae. White ascomata, blunt or subcapitate peridial appendages, pitted ascospores, and tuberculate conidia suggest it to be a new Neogymnomyces , and this was confirmed by parsimony analyses of LSU and ITS nrDNA sequences. Following recent phylogenetic analyses, the morphological and physiological features of order Onygenales and its families are re–examined and discussed. After the introduction of a new species, Neogymnomyces is reviewed and compared with all other genera in Onygenaceae. The Chrysosporium imperfect state of Neogymnomyces virgineus is described and compared to the anamorph of N. demonbreunii . It is also compared to the atypical Chrysosporium merdarium and to several other Chrysosporium species with echinulate to verrucose–tuberculate conidia, isolated from guano, dung, and nitrogen–rich soils in caves. The onygenalean fungi isolated from any kind of dung are discussed and their facultative coprophily ascribed to variable faecal contents of keratin or other degradable substances. A key to the families and genera of the Onygenales is provided.
