TY - JOUR
T1 - Cloning of the Aspergillus fumigatus squalene epoxidase gene.
AU - Liu, Wei
AU - May, Gregory S.
AU - Kontoyiannis, Dimitrios P.
AU - Li, Ruo yu
N1 - Copyright:
This record is sourced from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
PY - 2004/10
Y1 - 2004/10
N2 - OBJECTIVE: To clone Aspergillus fumigatus squalene epoxidase gene and to further investigate its role in terbinafine resistance. METHODS: The A.fumigatus genomic DNA library was transformed into pyrG-A. fumigatus strain protoplasts with polyethylene glycol-mediated transformation protocol. TRB-resistant pyrG+ transformants were then isolated by being plated on MM-U with TRB (0.625 mg/L) plates. After confirmation of terbinafine-resistance by using both disk diffusion and NCCLS M38-A microdilution antifungal susceptibility testing, the gene conferring terbinafine-resistance was identified. Finally, the gene was cloned and retransformed into pyrG-A. fumigatus strain. RESULTS: From a total of 5x10(4) transformants, one TRB-resistant pyrG+ transformant was isolated, which showed the terbinafine-specific resistance without cross-resistance to any other antifungals. A. fumigatus squalene epoxidase gene was further identified to confer this terbinafine-resistance. As a result, the complete A. fumigatus squalene epoxidase gene was firstly cloned. Finally, the transformants with extra copies of A. fumigatus squalene epoxidase gene, again, showed the specific resistance to terbinafine. CONCLUSION: Extra copies of A. fumigatus squalene epoxidase gene, which was cloned for the first time in this study, could result in A. fumigatus resistance to terbinafine. This is a novel mechanism of terbinafine-resistance that needs further investigation for its clinical significance.
AB - OBJECTIVE: To clone Aspergillus fumigatus squalene epoxidase gene and to further investigate its role in terbinafine resistance. METHODS: The A.fumigatus genomic DNA library was transformed into pyrG-A. fumigatus strain protoplasts with polyethylene glycol-mediated transformation protocol. TRB-resistant pyrG+ transformants were then isolated by being plated on MM-U with TRB (0.625 mg/L) plates. After confirmation of terbinafine-resistance by using both disk diffusion and NCCLS M38-A microdilution antifungal susceptibility testing, the gene conferring terbinafine-resistance was identified. Finally, the gene was cloned and retransformed into pyrG-A. fumigatus strain. RESULTS: From a total of 5x10(4) transformants, one TRB-resistant pyrG+ transformant was isolated, which showed the terbinafine-specific resistance without cross-resistance to any other antifungals. A. fumigatus squalene epoxidase gene was further identified to confer this terbinafine-resistance. As a result, the complete A. fumigatus squalene epoxidase gene was firstly cloned. Finally, the transformants with extra copies of A. fumigatus squalene epoxidase gene, again, showed the specific resistance to terbinafine. CONCLUSION: Extra copies of A. fumigatus squalene epoxidase gene, which was cloned for the first time in this study, could result in A. fumigatus resistance to terbinafine. This is a novel mechanism of terbinafine-resistance that needs further investigation for its clinical significance.
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M3 - Article
C2 - 15489926
AN - SCOPUS:44249092846
SN - 1671-167X
VL - 36
SP - 476
EP - 482
JO - Beijing da xue xue bao. Yi xue ban = Journal of Peking University. Health sciences
JF - Beijing da xue xue bao. Yi xue ban = Journal of Peking University. Health sciences
IS - 5
ER -