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Aspergillus pragensis sp nov discovered during molecular reidentification of clinical isolates belonging to Aspergillus section Candidi

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Abstract

The identity of nine clinical isolates recovered from Czech patients and presumptively identified as Aspergillus sp. section Candidi based on colony morphology was revised using sequences of beta-tubulin, calmodulin gene sequence, and internal transcribed spacer rDNA. Six isolates were from suspected and proven onychomycosis, one from otitis externa, and two associated with probable invasive aspergillosis. The results showed that one Aspergillus candidus isolate was the cause of otitis externa, and both isolates obtained from sputa of patients with probable invasive aspergillosis were reidentified as A. carneus (sect. Terrei) and A. flavus (sect. Flavi). Three isolates from nail scrapings were identified as A. tritici, a verified agent of nondermatophyte onychomycosis. One isolate from toenail was determined to be A. candidus and the two isolates belonged to a hitherto undescribed species, Aspergillus pragensis sp. nov. This species is well supported by phylogenetic analysis based on beta-tubulin and calmodulin gene and is distinguishable from other members of sect. Candidi by red-brown reverse on malt extract agar, slow growth on Czapek-Dox agar and inability to grow at 37 degrees C. A secondary metabolite analysis was also provided with comparison of metabolite spectrum to other species. Section Candidi now encompasses five species for which a dichotomous key based on colony characteristics is provided. All clinical isolates were tested for susceptibilities to selected antifungal agents using the Etest and disc diffusion method. Overall sect. Candidi members are highly susceptible to common antifungals.

Czech Republic Europe Palearctic region invasive aspergillosis Aspergillosis (MeSH) fungal disease epidemiology onychomycosis Onychomycosis (MeSH) integumentary system disease fungal disease otitis Otitis (MeSH) ear disease Fungi Plantae (Fungi Microorganisms Nonvascular Plants Plants) - Fungi Imperfecti or Deuteromycetes [15500*] Aspergillus flavus species Aspergillus carneus species Aspergillus pragensis species new species pathogen description Aspergillus Candidi species pathogen Primates Mammalia Vertebrata Chordata Animalia (Animals Chordates Humans Mammals Primates Vertebrates) - Hominidae [86215] human common host Aspergillus carneus Bt2a gene [Fungi Imperfecti or Deuteromycetes] expression Aspergillus pragensis beta-tubulin gene [Fungi Imperfecti or Deuteromycetes] expression Aspergillus pragensis calmodulin gene [Fungi Imperfecti or Deuteromycetes] expression internal transcribed spacer rDNA 00504 General biology - Taxonomy nomenclature and terminology 03502 Genetics - General 03504 Genetics - Plant 03508 Genetics - Human 11102 Anatomy and Histology - Gross anatomy 12502 Pathology - General 18506 Integumentary system - Pathology 20006 Sense organs - Pathology 36008 Medical and clinical microbiology - Mycology 50506 Botany: general and systematic - Fungi 51000 Morphology anatomy and embryology of plants 62520 Chordata: general and systematic - Mammalia Biochemistry and Molecular Biophysics Human Medicine Medical Sciences phylogenetic analysis mathematical and computer techniques Infection Molecular Genetics Otolaryngology Systematics and Taxonomy MYCOLOGY VETERINARY TAXONOMIC REVISION PHYSIOLOGICAL DATA DNA-SEQUENCES COLOR MUTANTS ONYCHOMYCOSIS TAICHUNGENSIS METABOLITES FUMIGATUS PENICILLIUM INFECTIONS Aspergillus candidus Aspergillus tritici antifungal susceptibility testing nondermatophyte onychomycosis otomycosis polyphasic approach