Molecular phylogenetics of Candida albicans
Molecular phylogenetics of Candida albicans
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DOI：
10.1128/ec.00041-07
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发表时间：
2007-06-01
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影响因子：
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通讯作者：
d'Enfert, Christophe
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文献类型：
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作者：
Odds, Frank C.;Bougnoux, Marie-Elisabeth;d'Enfert, Christophe
我们分析了 1,391 个白色念珠菌分离株的多位点序列分型 (MLST)、ABC 分型、交配型样位点 (MAT) 状态和抗真菌敏感性数据。 MLST 可以将几乎所有 (96.7%) 的分离株分配到 17 个进化枝之一。 eBURST 分析揭示了 53 个克隆簇。二倍体序列 69 型是最常见的 MLST 菌株类型，也是最大克隆簇的创建者，在世界各地的分离株中都发现了实例。通过单变量方差分析，ABC 类型和地理起源显示进化枝之间具有统计学显着差异，但解剖来源和抗真菌药敏数据没有显着相关性。一项仅限于欧洲分离株的单独分析，从而最大限度地减少地理影响，显示五个人口最多的分支中血液分离株、共生携带和浅表感染的比例存在显着差异。具有低抗真菌敏感性的分离株比例对于 MAT 纯合 a/a 类型最高，然后是 α/α 类型，对于杂合 a/α 类型最低。 MLST 定义的进化枝树与由测序的单个基因片段生成的树不一致，这意味着每个片段都有单独的进化历史。位点之间和位点内的核酸变异分析支持重组。计算单倍型分析显示重组事件频率很高，这表明分离株具有类似于有性繁殖物种的混合进化历史。
We analyzed data on multilocus sequence typing (MLST), ABC typing, mating type-like locus (MAT) status, and antifungal susceptibility for a panel of 1,391 Candida albicans isolates. Almost all (96.7%) of the isolates could be assigned by MLST to one of 17 clades. eBURST analysis revealed 53 clonal clusters. Diploid sequence type 69 was the most common MLST strain type and the founder of the largest clonal cluster, and examples were found among isolates from all parts of the world. ABC types and geographical origins showed statistically significant variations among clades by univariate analysis of variance, but anatomical source and antifungal susceptibility data were not significantly associated. A separate analysis limited to European isolates, thereby minimizing geographical effects, showed significant differences in the proportions of isolates from blood, commensal carriage, and superficial infections among the five most populous clades. The proportion of isolates with low antifungal susceptibility was highest for MAT homozygous a/a types and then alpha/alpha types and was lowest for heterozygous a/alpha types. The tree of clades defined by MLST was not congruent with trees generated from the individual gene fragments sequenced, implying a separate evolutionary history for each fragment. Analysis of nucleic acid variation among loci and within loci supported recombination. Computational haplotype analysis showed a high frequency of recombination events, suggesting that isolates had mixed evolutionary histories resembling those of a sexually reproducing species.