Characterization and genetic variability of feed-borne and clinical animal/human Aspergillus fumigatus strains using molecular markers

PENA G.A., ; COELHO I., ; REYNOSO M.M., ; SOLEIRO C., ; CAVAGLIERI L.R.

MEDICAL MYCOLOGY

TAYLOR & FRANCIS LTD

Lugar: Londres; Año: 2015 vol. 53 p. 699 - 708

1369-3786

Aspergillus fumigatus, the major etiological agent of human and animal aspergillosis, is a toxigenic fungus largely regarded as a single species by macroscopic and microscopic features. However, molecular studies have demonstrated that several morphologically identifiedA.fumigatusstrainsmightbegeneticallydistinct.Thisworkwasaimedtoapply PCR-restrictionlengthfragmentpolymorphisms(PCR-RFLP)andrandomamplificationof polymorphicDNA(RAPD)molecularmarkerstocharacterizeasetoffeed-borneandclinical A. fumigatus sensu lato strains isolated from Argentina and Brazil and to determine and compare their genetic variability. All A. fumigatus strains had the same band profile and those typical of A. fumigatus sensu stricto positive controls by PCR-RFLP. Moreover, all Argentinian and Brazilian strains typified by RAPD showed similar band patterns to each other and to A. fumigatus sensu stricto reference strains regardless of their isolationsource(animalfeedsorhuman/animalclinicalcases)and geographic origin.Genetic similarity coefficients ranged from 0.61 to 1.00,but almostallisolatesshowed78%ofgenetic similarly suggesting that genetic variability was found at intraspecific level. Finally, benAsequencingconfirmeditsidentificationasA.fumigatussensustrictospecies.Theseresults suggest that A. fumigatus sensu stricto is a predominant species into Aspergillus sectionFumigatifoundinanimalenvironmentsaswellasinhuman/animalclinicalcases, while other species may be rarely isolated. The strains involved in human and animal aspergillosis could come from the environment where this fungus is frequently found. Rural workers and animals would be constantly exposed.