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Diversity and specificity of microsatellites within Aspergillus section Fumigati
Araujo Ricardo,Amorim António,Gusm?o Leonor
BMC Microbiology , 2012, DOI: 10.1186/1471-2180-12-154
Abstract: Background Microsatellites (or short tandem repeats, STRs) are the genetic markers of choice for studying Aspergillus fumigatus molecular epidemiology due to its reproducibility and high discrimination power. However, the specificity of these markers must be investigated in a group of isolates from closely related species. The aim of this work was to test a microsatellite-based PCR multiplex previously designed for A. fumigatus in a set of species belonging to section Fumigati, namely Aspergillus fumigatiaffinis, Aspergillus lentulus, Aspergillus novofumigatus, Aspergillus unilateralis, Aspergillus viridinutans, Neosartorya fischeri, Neosartorya hiratsukae, Neosartorya pseudofischeri and Neosartorya udagawae. Results The reference A. fumigatus strain ATCC 46645 was easily genotyped in standard conditions showing a final electrophoretic profile of 8 expected peaks corresponding to each microsatellite locus. Inversely, no peaks were observed for all other species from section Fumigati, with an exception for marker MC6b in A. unilateralis. By screening the genome sequence of Neosartorya fischeri NRRL 181, the results showed that MC3, MC6a and MC7 might be employed for N. fischeri genotyping since these markers present several repeats of each motif. The accumulation of insertions and deletions was frequently observed in the genomic regions surrounding the microsatellites, including those where the A. fumigatus primers are located. The amplification of microsatellite markers in less stringent amplification conditions resulted in a distinct electrophoretic profile for species within section Fumigati. Conclusions Therefore, the microsatellite-based PCR multiplex allow simple identification of A. fumigatus and, with a slight modification of temperature conditions, it also allows discriminating other pathogenic species within section Fumigati, particularly A. fumigatiaffinis, N. fischeri and N. udagawae.
Polyphasic taxonomy of Aspergillus section Fumigati and its teleomorph Neosartorya
R.A. Samson,S. Hong,S.W. Peterson,J.C. Frisvad
Studies in Mycology , 2007,
Abstract: The taxonomy of Aspergillus section Fumigati with its teleomorph genus Neosartorya is revised. The species concept is based on phenotypic (morphology and extrolite profiles) and molecular (β-tubulin and calmodulin gene sequences) characters in a polyphasic approach. Four new taxa are proposed: N. australensis N. ferenczii, N. papuaensis and N. warcupii. All newly described and accepted species are illustrated. The section consists of 33 taxa: 10 strictly anamorphic Aspergillus species and 23 Neosartorya species. Four other Neosartorya species described previously were not available for this monograph, and consequently are relegated to the category of doubtful species
Phenotypic characteristics of isolates of Aspergillus section Fumigati from different geographic origins and their relationships with genotypic characteristics
María Frías-De León, Monserrat Zavala-Ramírez, Susana Córdoba, Gerardo Zú?iga, Esperanza Duarte-Escalante, Armando Pérez-Torres, Armando Zepeda-Rodríguez, Irma López-Martínez, María Buitrago, María del Rocío Reyes-Montes
BMC Infectious Diseases , 2011, DOI: 10.1186/1471-2334-11-116
Abstract: We analyzed the phenotypic characteristics (macro- and micromorphology, conidial size, vesicles size, antifungal susceptibility and thermotolerance at 28, 37 and 48°C) of A. section Fumigati isolates from Mexico (MX), Argentina (AR), Peru (PE) and France (FR). The results were analyzed using analysis of variance (ANOVA) and Tukey's multiple comparison test to detect significant differences. Two dendrograms among isolates were obtained with UPGMA using the Euclidean distance index. One was drawn for phenotypic data, and the other for phenotypic and genotypic data. A PCoA was done for shown isolates in a space of reduced dimensionality. In order to determine the degree of association between the phenotypic and genotypic characteristics AFLP, we calculated the correlation between parwise Euclidean distance matrices of both data sets with the nonparametric Mantel test.No variability was found in the macromorphology of the studied isolates; however, the micromorphology and growth rate showed that the PE isolates grew at a faster rate and exhibited the widest vesicles in comparison to the isolates from MX, AR and FR. The dendrogram constructed with phenotypic data showed three distinct groups. The group I and II were formed with isolates from PE and FR, respectively, while group III was formed with isolates from MX and AR. The dendrogram with phenotypic and genotypic data showed the same cluster, except for an isolate from FR that formed a separate cluster. This cluster was confirmed using PCoA. The correlation between the phenotypic and genotypic data of the isolates revealed a statistically significant association between these characteristics.The PE isolates showed specific phenotypic characteristics that clearly differentiate them from the rest of the isolates, which matches the genotypic data. The correlation between the phenotypic and genotypic characteristics showed a statistically significant association. In conclusion, phenotypic and genotypic methods together in
Rapid Host Defense against Aspergillus fumigatus Involves Alveolar Macrophages with a Predominance of Alternatively Activated Phenotype  [PDF]
Shikha Bhatia,Mingjian Fei,Manohar Yarlagadda,Zengbiao Qi,Shizuo Akira,Shinobu Saijo,Yoichiro Iwakura,Nico van Rooijen,Gregory A. Gibson,Claudette M. St. Croix,Anuradha Ray,Prabir Ray
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0015943
Abstract: The ubiquitous fungus Aspergillus fumigatus is associated with chronic diseases such as invasive pulmonary aspergillosis in immunosuppressed patients and allergic bronchopulmonary aspergillosis (ABPA) in patients with cystic fibrosis or severe asthma. Because of constant exposure to this fungus, it is critical for the host to exercise an immediate and decisive immune response to clear fungal spores to ward off disease. In this study, we observed that rapidly after infection by A. fumigatus, alveolar macrophages predominantly express Arginase 1 (Arg1), a key marker of alternatively activated macrophages (AAMs). The macrophages were also found to express Ym1 and CD206 that are also expressed by AAMs but not NOS2, which is expressed by classically activated macrophages. The expression of Arg1 was reduced in the absence of the known signaling axis, IL-4Rα/STAT6, for AAM development. While both Dectin-1 and TLR expressed on the cell surface have been shown to sense A. fumigatus, fungus-induced Arg1 expression in CD11c+ alveolar macrophages was not dependent on either Dectin-1 or the adaptor MyD88 that mediates intracellular signaling by most TLRs. Alveolar macrophages from WT mice efficiently phagocytosed fungal conidia, but those from mice deficient in Dectin-1 showed impaired fungal uptake. Depletion of macrophages with clodronate-filled liposomes increased fungal burden in infected mice. Collectively, our studies suggest that alveolar macrophages, which predominantly acquire an AAM phenotype following A. fumigatus infection, have a protective role in defense against this fungus.
Aspergillus felis sp. nov., an Emerging Agent of Invasive Aspergillosis in Humans, Cats, and Dogs  [PDF]
Vanessa R. Barrs, Tineke M. van Doorn, Jos Houbraken, Sarah E. Kidd, Patricia Martin, Maria Dolores Pinheiro, Malcolm Richardson, Janos Varga, Robert A. Samson
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0064871
Abstract: We describe a novel heterothallic species in Aspergillus section Fumigati, namely A. felis (neosartorya-morph) isolated from three host species with invasive aspergillosis including a human patient with chronic invasive pulmonary aspergillosis, domestic cats with invasive fungal rhinosinusitis and a dog with disseminated invasive aspergillosis. Disease in all host species was often refractory to aggressive antifungal therapeutic regimens. Four other human isolates previously reported as A. viridinutans were identified as A. felis on comparative sequence analysis of the partial β-tubulin and/or calmodulin genes. A. felis is a heterothallic mold with a fully functioning reproductive cycle, as confirmed by mating-type analysis, induction of teleomorphs within 7 to 10 days in vitro and ascospore germination. Phenotypic analyses show that A. felis can be distinguished from the related species A. viridinutans by its ability to grow at 45°C and from A. fumigatus by its inability to grow at 50°C. Itraconazole and voriconazole cross-resistance was common in vitro.
Aspergillus fumigatus in Poultry  [PDF]
Pascal Arné,Simon Thierry,Dongying Wang,Manjula Deville,Guillaume Le Loc'h,Ana s Desoutter,Fran oise Féménia,Adéla de Nieguitsila,Weiyi Huang,René Chermette,Jacques Guillot
International Journal of Microbiology , 2011, DOI: 10.1155/2011/746356
Abstract: Aspergillus fumigatus remains a major respiratory pathogen in birds. In poultry, infection by A. fumigatus may induce significant economic losses particularly in turkey production. A. fumigatus develops and sporulates easily in poor quality bedding or contaminated feedstuffs in indoor farm environments. Inadequate ventilation and dusty conditions increase the risk of bird exposure to aerosolized spores. Acute cases are seen in young animals following inhalation of spores, causing high morbidity and mortality. The chronic form affects older birds and looks more sporadic. The respiratory tract is the primary site of A. fumigatus development leading to severe respiratory distress and associated granulomatous airsacculitis and pneumonia. Treatments for infected poultry are nonexistent; therefore, prevention is the only way to protect poultry. Development of avian models of aspergillosis may improve our understanding of its pathogenesis, which remains poorly understood.
Aspergillus fumigatus in Poultry  [PDF]
Pascal Arné,Simon Thierry,Dongying Wang,Manjula Deville,Guillaume Le Loc'h,Ana?s Desoutter,Fran?oise Féménia,Adéla?de Nieguitsila,Weiyi Huang,René Chermette,Jacques Guillot
International Journal of Microbiology , 2011, DOI: 10.1155/2011/746356
Abstract: Aspergillus fumigatus remains a major respiratory pathogen in birds. In poultry, infection by A. fumigatus may induce significant economic losses particularly in turkey production. A. fumigatus develops and sporulates easily in poor quality bedding or contaminated feedstuffs in indoor farm environments. Inadequate ventilation and dusty conditions increase the risk of bird exposure to aerosolized spores. Acute cases are seen in young animals following inhalation of spores, causing high morbidity and mortality. The chronic form affects older birds and looks more sporadic. The respiratory tract is the primary site of A. fumigatus development leading to severe respiratory distress and associated granulomatous airsacculitis and pneumonia. Treatments for infected poultry are nonexistent; therefore, prevention is the only way to protect poultry. Development of avian models of aspergillosis may improve our understanding of its pathogenesis, which remains poorly understood. 1. Introduction Aspergillus fumigatus is considered as a major respiratory pathogen in birds. This filamentous fungus was first found in the lungs of a bustard (Otis tarda) in 1863 by Fresenius. Other species like A. flavus, A. niger, A. nidulans, and A. terreus may also be isolated from avian cases of aspergillosis (sometimes in mixed infections) but much less frequently than A. fumigatus [1–6]. Active fungal proliferation and sporulation of A. fumigatus on organic material produce large amounts of airborne small-sized conidia that are easily dispersed in air, then potentially inhaled and deposited deep in the respiratory tract. Susceptible hosts will develop polymorphic clinical forms in relation to either localized or disseminated lesions. Acute aspergillosis generally occurs in young birds resulting in high morbidity and mortality. The chronic form is sporadic. It causes lesser mortality and generally affects older birds, especially breeders in poultry, presenting a compromised immune system due to poor husbandry conditions [4, 7]. A. fumigatus has been isolated from lesions in wild birds since the early 1800s. Major die-offs of free-ranging wild birds have been reported from waterfowl, gulls, and corvids following dumping of mouldy waste grains in areas where birds feed [6, 8–10]. Infection by A. fumigatus is also found in birds of prey, penguins, and parrots held in captivity [7, 11]. Incidence may be elevated in debilitated birds sheltered in wildlife centres and severely impair rehabilitation success [12, 13]. Infection by Aspergillus sp. has been reported in almost all domesticated
Glucoamylase from the Isolate Aspergillus fumigatus  [PDF]
H.M. Cherry,Md. Towhid Hossain,M.N. Anwar
Pakistan Journal of Biological Sciences , 2004,
Abstract: Aspergillus fumigatus Fresenius was isolated from goat`s rumen and exhibited highest amylase production at temperature 37 C, medium pH 7.0 and 3 days of incubation period. Four percent starch as carbon source and 0.25% (NH4)2HPO4 as nitrogen source was found to induce amylase production by the isolate Aspergillus fumigatus. Maximum glucoamylase activity was achieved at 35 C temperature and pH 7.0 along with 4% starch as substrate concentration during enzyme-substrate reaction.
Taxonomic revision of Aspergillus section Clavati based on molecular, morphological and physiological data
J. Varga,M. Due,J.C. Frisvad,R.A. Samson
Studies in Mycology , 2007,
Abstract: Aspergillus section Clavati has been revised using morphology, secondary metabolites, physiological characters and DNA sequences. Phylogenetic analysis of β-tubulin, ITS and calmodulin sequence data indicated that Aspergillus section Clavati includes 6 species, A. clavatus (synonyms: A. apicalis, A. pallidus), A. giganteus, A. rhizopodus, A. longivesica, Neocarpenteles acanthosporus and A. clavatonanicus. Neocarpenteles acanthosporus is the only known teleomorph of this section. The sister genera to Neocarpenteles are Neosartorya and Dichotomomyces based on sequence data. Species in Neosartorya and Neocarpenteles have anamorphs with green conidia and share the production of tryptoquivalins, while Dichotomomyces was found to be able to produce gliotoxin, which is also produced by some Neosartorya species, and tryptoquivalines and tryptoquivalones produced by members of both section Clavati and Fumigati. All species in section Clavati are alkalitolerant and acidotolerant and they all have clavate conidial heads. Many species are coprophilic and produce the effective antibiotic patulin. Members of section Clavati also produce antafumicin, tryptoquivalines, cytochalasins, sarcins, dehydrocarolic acid and kotanins (orlandin, desmethylkotanin and kotanin) in species specific combinations. Another species previously assigned to section Clavati, A. ingratus is considered a synonym of Hemicarpenteles paradoxus, which is phylogenetically very distantly related to Neocarpenteles and section Clavati
Trial of Aspergillus fumigatus Vaccine in Broiler Chicks
Clara N. Kwanashie,Jarlath U. Umoh,Haruna M. Kazeem,Paul A. Abdu
Research Journal of Animal Sciences , 2012, DOI: 10.3923/rjnasci.2012.72.75
Abstract: There is a scarcity of information on the effect of vaccine against aspergillosis in Zaria and Kaduna areas. Thus, this study was conducted to determine the efficacy of an Aspergillus fumigatus germling vaccine. The methodologies used in this study included Aspergillus spore production, determination of LD50, preparation of the germling vaccine and testing the efficacy on broiler chicks. Three groups of 4 days old broilers were exposed to 4.2-5.8x108 cfu g-1 lung tissue of A. fumigatus. The calculated amount of A. fumigatus that killed 50% of the broilers was 5.8x107.4. A. fumigatus was recovered 4 weeks post exposure. A germling vaccine of A. fumigatus was administered to 4 days old broilers using the ocular route. The trial vaccine showed 40% protection when administered to chicks 2 weeks prior to challenge with A. fumigatus spores. It is recommended that levels of A. fumigatus spores should not rise to 5.8x107.4 cfu g-1 lung tissue in poultry houses. Adjuvants can be added to the vaccine to raise the level of protection using different routes of administration and vaccinating at an older age.
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