title: High-level expression of cyp51B in azole-resistant clinical Aspergillus fumigatus isolates.
abstract: OBJECTIVE
  Resistance to azole antifungal drugs in Aspergillus fumigatus that is not mediated by target gene mutations is now common in some locations. The aim of this study was to investigate possible new mechanisms of resistance in non-target resistance.
  
  
  METHODS
  Twelve azole-resistant A. fumigatus isolates previously shown not to carry mutations in cyp51A were tested to determine whether the alternative cyp51B gene was overexpressed.
  
  
  RESULTS
  Of 12 isolates one showed overinduction of cyp51B after exposure to itraconazole and another showed high constitutive expression of cyp51B.
  
  
  CONCLUSIONS
  cyp51B overexpression is a possible azole resistance mechanism in A. fumigatus.
authors.affiliation: School of Translational Medicine, Manchester Academic Health Science Centre, Faculty of Medicine and Human Sciences,  2nd Floor Education & Research Centre, University Hospital of South Manchester, University of Manchester, Manchester M23 9LT,  UK.
authors.forename: A
authors.initials: A
authors.lastname: Buied
authors.forename: C B
authors.initials: CB
authors.lastname: Moore
authors.forename: D W
authors.initials: DW
authors.lastname: Denning
authors.forename: P
authors.initials: P
authors.lastname: Bowyer
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D001228:Aspergillosis / Q000382:microbiology; D001232:Aspergillus fumigatus / Q000187:drug effects* / Q000201:enzymology* / Q000302:isolation & purification; D001393:Azoles / Q000494:pharmacology*; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis*; D025141:Drug Resistance, Fungal; D005656:Fungal Proteins / Q000096:biosynthesis*; D015870:Gene Expression; D006801:Humans; D015854:Up-Regulation
chemical_list: D000935:Antifungal Agents; D001393:Azoles; D005656:Fungal Proteins; D003577:Cytochrome P-450 Enzyme System; C465527:cytochrome P-450 CYP51B, Aspergillus