title: Screening method to identify inhibitors of siderophore biosynthesis in the opportunistic fungal pathogen, Aspergillus fumigatus.
abstract: OBJECTIVE
  Aspergillus fumigatus is the most common cause of airborne mould infections in immunocompromised patients worldwide. Our aim was to develop a method to identify agents that inhibit siderophore biosynthesis because this pathway is unique to the fungus and is essential for virulence.
  
  
  RESULTS
  A high-throughput two-step screening assay was developed using 96-well plates in which fungal growth and siderophore production is assessed spectrophotometrically. If a compound inhibits growth only in iron-limited medium (screen 1), its effect on siderophore production is then determined (screen 2). The proof of concept was demonstrated using a known antifungal agent, amphotericin B, and a strain of A. fumigatus deficient in siderophore production.
  
  
  CONCLUSIONS
  The two-stage screening method clearly identified growth defects in A. fumigatus related specifically to siderophore biosynthesis.
  
  
  CONCLUSIONS
  The increasing incidence of life-threatening fungal infections has produced an urgent need for novel antifungal agents. The method described in this report will facilitate the identification of novel antifungal compounds that inhibit a pathway critical for A. fumigatus virulence and have a reduced probability of affecting host metabolism.
authors.affiliation: Department of Biological Sciences, Simon Fraser University, Burnaby BC, Canada.
authors.forename: L J
authors.initials: LJ
authors.lastname: Pinto
authors.forename: M M
authors.initials: MM
authors.lastname: Moore
mesh_terms: D000666:Amphotericin B / Q000494:pharmacology; D000935:Antifungal Agents / Q000494:pharmacology*; D001232:Aspergillus fumigatus / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism / Q000472:pathogenicity; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D006801:Humans; D017262:Siderophores / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D013053:Spectrophotometry / Q000379:methods; D037521:Virulence Factors / Q000037:antagonists & inhibitors* / Q000096:biosynthesis
chemical_list: D000935:Antifungal Agents; D017262:Siderophores; D037521:Virulence Factors; D000666:Amphotericin B