Rapid identification of Aspergillus fumigatus within the section Fumigati

Abstract

BackgroundNew fungal species that are morphologically similar to Aspergillus fumigatus were recently described and included in section Fumigati. Misidentification of such fungal species, particularly of the human pathogens, Aspergillus lentulus, Neosartorya fischeri, Neosartorya hiratsukae, Neosartorya pseudofischeri and Neosartorya udagawae, has been increasingly reported by numerous clinical labs. Nevertheless, A. fumigatus still accounts for more than 90% of all invasive aspergillosis cases. The purpose of the present study was to develop a rapid method for the molecular identification of A. fumigatus to distinguish it from other species within the section Fumigati.ResultsA multiplex PCR was developed using prior information based on β-tubulin (βtub) and rodlet A (rodA) partial gene sequences. PCR amplification of βtub and rodA fragments resulted in a distinctive electrophoretic pattern in A. fumigatus and N. udagawae. The polymorphisms found in the smallest amplified sequence of βtub (153 bp) and rodA (103 bp) genes were then compared among and within species of this taxonomic section. βtub was able to differentiate among 13 individual species and two groups of species that included the pathogenic fungus A. lentulus. A more limited number of sequences were available for rodA; nevertheless, we were able to distinguish Aspergillus viridinutans, N. hiratsukae and N. udagawae.ConclusionsThe assay described in the present study proved to be specific and highly reproducible, representing a fast and economic way of targeting molecular identification of the relevant mould, A. fumigatus, in clinical laboratories.

An alternative host model of a mixed fungal infection by azole susceptible and resistantAspergillusspp strains

“…Among them, the more usual targets have been b-tubuline, calmodulin, and rodlet A genes. 6,35 The use of single copy genes shows better discriminatory power but have the inconvenience of lack of sensitivity when clinical samples such as blood or BALs are used. In order to improve this, we developed a multiplex quantitative one-step nested PCR (MN-PCR) targeting the intron sequences of the azole target, 14-a sterol demethylase (cyp51A).…”

Identification and characterization of Aspergillus fumigatus isolates from broilers

“…Species within the section Fumigati have been described as human pathogens, particularly A. lentulus, A. viridinutans, Neosartorya pseudofischeri and N. udagawae (Serrano et al 2011). Based on these reports, species within the section Fumigati may be involved in bird's diseases or may be present in the lungs of healthy birds.…”

“…Fungal DNA was frozen at -20 0 C. Molecular identification of Aspergillus fumigatus. Molecular identification was performed using specific primers for identification of Aspergillus section Fumigati and A. fumigatus (Table 1) (Serrano et al 2011). Multiplex PCR amplification was performed in a 5μl final volume containing 1 μL of genomic DNA (1-5ng/μL), 2.5μL of 2x Qiagen multiplex PCR master mix (Qiagen, Hilden, Germany) and 0.5μL of each primer (for a 0.2μM final concentration of each primer).…”

“…Molecular methods for the identification is recommended since many species macroscopic and microscopically similar to this species have been described belonging to Section Fumigati, which sometimes cause difficulties to the correct diagnosis (Balajee et al 2005, Serrano et al 2011. Microsatellites are the genetic markers of choice for studying A. fumigatus molecular epidemiology since a microsatellite-based multiplex PCR has been proved to be specific, highly reproducible, fast and economic way of targeting molecular identification of A. fumigatus in human clinical laboratories (Araujo et al 2009, Araujo et al 2012.…”

Notas micológicas XI:Tritirachium oryzae, Paecilomyces formosus y alcances en la Sección Fumigati de Aspergillus con énfasis en el complejo Aspergillus viridinutans

“…A. fumigatus es variable en su macro y micromorfología y no es fácil separarlo de otras especies relacionadas solo en base a morfología (vea fig. 3 d , 2005a-2006-2009Serrano et al, 2011). Muchos aislados hetero y homotálicos de la sección, semejan fuertemente A. fumigatus, pero demuestran un crecimiento lento a 37ºC o una baja esporulación en los cultivos y no crecen generalmente a 50 ºC, pero si a 47°, 45°C o solo hasta 42°C, como es el caso específico de A.udagawae , que es capaz de crecer a10°C pero no puede crecer a más de 42°C y sus conidios necesitan un largo período de incubación para germinar a 37°C.…”