Open AccessErg11 mutations associated with azole resistance in clinical isolates of C andida albicans
Author(s) -
Xiang MingJie,
Liu JinYan,
Ni PeiHua,
Wang Shengzheng,
Shi Ce,
Wei Bing,
Ni YuXing,
Ge HaiLiang
Publication year - 2013
Publication title -
fems yeast research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 92
eISSN - 1567-1364
pISSN - 1567-1356
DOI - 10.1111/1567-1364.12042
Subject(s) - azole , biology , candida albicans , lanosterol , fluconazole , gene , point mutation , genetics , mutation , itraconazole , corpus albicans , mutagenesis , drug resistance , microbiology and biotechnology , cytochrome p450 , enzyme , biochemistry , antifungal , sterol , cholesterol
The widespread use of azoles has led to increasing azole resistance among C andida albicans strains. One mechanism of azole resistance involves point mutations in the ERG 11 gene, which encodes the target enzyme (cytochrome P 450 lanosterol 14α‐demethylase). In the present study, we amplified and sequenced the ERG 11 gene of 23 C . albicans clinical isolates. Seventeen mutations encoding distinct amino acid substitutions were found, of which seven ( K 143 Q , Y 205 E , A 255 V , E 260 V , N 435 V , G 472 R , and D 502 E ) were novel. We further verified the contribution of the amino acid substitutions to azole resistance using site‐directed mutagenesis of the ERG 11 gene to recreate these mutations for heterologous expression in S accharomyces cerevisiae . We observed that substitutions A 114 S , Y 132 H , Y 132 F , K 143 R , Y 257 H , and a new K 143 Q substitution contributed to significant increases (≧ fourfold) in fluconazole and voriconazole resistance; changes in itraconazole resistance were not significant (≦ twofold).