High-level expression of cyp51B in azole-resistant clinical Aspergillus fumigatus isolates.
نویسندگان
چکیده
OBJECTIVES 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.
منابع مشابه
Examination of cyp51A and cyp51B expression level of the first Polish azole resistant clinical Aspergillus fumigatus isolate.
Aspergillus fumigatus is one of the most prevalent airborne fungal pathogens causing infections worldwide. Most A. fumigatus strains are susceptible to azoles, which are administered as the first line therapeutics. However, during last decade the acquired resistance to triazoles by these species has been described. There is a number of publications concerning the examination of clinical A. fumi...
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Multiple Aspergillus fumigatus isolates from a patient with two aspergillomas complicating chronic pulmonary aspergillosis were pan-azole resistant. Microsatellite typing was identical for all isolates despite major phenotypic and some growth rate differences. Three different cyp51A mutations were found (G138C, Y431C, and G434C), of which the first two were demonstrated by heterologous expressi...
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OBJECTIVES Recent increases in triazole resistance in Aspergillus fumigatus have been attributed primarily to target site (cyp51A) mutations. A recent survey of resistant isolates in Manchester showed that >50% of resistant isolates had no mutation in cyp51A or its promoter. We investigated the mechanisms of resistance in clinical azole-resistant isolates without cyp51A mutations. METHODS Twe...
متن کاملAntifungal activity of terrestrial Streptomyces rochei strain HF391 against clinical azole -resistant Aspergillus fumigatus
Background and Purpose: Actinomycetes have been discovered as source of antifungal compounds that are currently in clinical use. Invasive aspergillosis (IA) due to Aspergillus fumigatus has been identified as individual drug-resistant Aspergillus spp. to be an emerging pathogen opportunities a global scale. This paper described the antifungal activity of one terrestrial actinomycete against the...
متن کاملAzole-resistant Aspergillus fumigatus in the environment of northern Italy, May 2011 to June 2012.
In recent years acquired azole resistance in Aspergillus fumigatus has been increasingly reported and a dominant mechanism of resistance (TR34/L98H) was found in clinical and environmental isolates. The aim of the present study was to investigate the prevalence of azole resistance in environmental A. fumigatus isolates collected in northern Italy. A. fumigatus grew from 29 of 47 soil samples an...
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عنوان ژورنال:
- The Journal of antimicrobial chemotherapy
دوره 68 3 شماره
صفحات -
تاریخ انتشار 2013