A point mutation in the 14alpha-sterol demethylase gene cyp51A contributes to itraconazole resistance in Aspergillus fumigatus.
نویسندگان
چکیده
The genes encoding 14alpha-sterol demethylases (cyp51A and cyp51B) were analyzed in 12 itraconazole (ITC)-resistant and three ITC-susceptible clinical isolates of Aspergillus fumigatus. Six ITC-resistant strains exhibited a substitution of another amino acid for glycine at position 54, which is located at a very conserved region of the Cyp51A protein. The cyp51A gene from the A. fumigatus wild-type strain (CM-237) was replaced with the mutated cyp51A gene copy of an ITC-resistant strain (AF-72). Two transformants exhibited resistance to ITC, both of which had incorporated the mutated copy of the cyp51A gene.
منابع مشابه
Targeted gene disruption of the 14-alpha sterol demethylase (cyp51A) in Aspergillus fumigatus and its role in azole drug susceptibility.
The role of Aspergillus fumigatus 14alpha-sterol demethylase (Cyp51A) in azole drug susceptibility was assessed. Targeted disruption of cyp51A in azole-susceptible and -resistant strains decreased MICs from 2- to 40-fold. The cyp51A mutants were morphologically indistinguishable from the wild-type strain, retaining the ability to cause pulmonary disease in neutropenic mice.
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 47 3 شماره
صفحات -
تاریخ انتشار 2003