Identification of extracellular siderophores of pathogenic strains of Aspergillus fumigatus.
Clinical and environmental isolates of Aspergillus fumigatus synthesized extracellular siderophores when grown in defined medium. Six hydroxamate siderophores were purified from culture filtrates and identified by thin layer chromatography. The most prominent siderophore was identified as N,N',N"-triacetylfusarinine C and the second most prominent siderophore was identified as ferricrocin. In addition, a hydrolytic product of N,N',N"-triacetylfusarinine C was identified. Three other siderophores were present in smaller amounts and were not identified. Since the same siderophores were produced by isolates from diseases of varying severity and from environmental material, it is unlikely that the extracellular siderophores function as virulence factors during infection. However, they may function as growth factors by mediating iron uptake by the fungus in the micro-environment of the inflammatory focus.
Nilius
A M
AM
Department of Pathology, Medical College of Wisconsin, Milwaukee 53226.
Farmer
S G
SG
D001232:Aspergillus fumigatus / Q000032:analysis* / Q000254:growth & development / Q000472:pathogenicity; D002855:Chromatography, Thin Layer; D003470:Culture Media; D007476:Ionophores / Q000032:analysis* / Q000302:isolation & purification; D007502:Iron Chelating Agents / Q000032:analysis* / Q000302:isolation & purification; D017262:Siderophores
D003470:Culture Media; D007476:Ionophores; D007502:Iron Chelating Agents; D017262:Siderophores