Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Teikyo University Institute of Medical Mycology, Tokyo, Japan.
J Med Microbiol. 2012 Jan;61(Pt 1):57-63. doi: 10.1099/jmm.0.036541-0. Epub 2011 Sep 8.
Microsporum ferrugineum, an uncommon causative agent of dermatophytosis, has restricted endemicity. Iranian strains suspected to be M. ferrugineum from two patients with tinea were analysed using the rDNA internal transcribed spacer (ITS) region and the partial β-tubulin (BT2) and translation elongation factor 1-α (TEF1) genes. Strains were compared to reference strains to differentiate M. ferrugineum from its relatives Microsporum canis and Microsporum audouinii. Inter-species differences for TEF1 and BT2 were found to be higher than for the ITS region, which is the current molecular standard for species identification in dermatophytes. Intra-species variation was zero for each of the markers. In silico analysis showed that the restriction enzymes BanI and BshNI were together sufficient to differentiate the three species based on TEF1, whereas a two-step digestion was needed with BT2 or the ITS region. The prevalence of M. ferrugineum in clinical samples in Iran appeared to be higher than suspected on the basis of routine phenotypic identification.
红色毛癣菌是一种罕见的皮肤癣菌病病原体，具有有限的地方性。从两名患有体癣的患者中分离出的疑似红色毛癣菌的伊朗菌株，使用 rDNA 内转录间隔区（ITS）区域以及部分β-微管蛋白（BT2）和翻译延伸因子 1-α（TEF1）基因进行了分析。将菌株与参考菌株进行比较，以将红色毛癣菌与其亲缘种犬小孢子菌和疣状毛癣菌区分开来。发现 TEF1 和 BT2 的种间差异高于 ITS 区域，后者是目前用于皮肤癣菌种鉴定的分子标准。每个标记的种内变异均为零。计算机分析表明，内切酶 BanI 和 BshNI 一起足以基于 TEF1 区分这三个种，而 BT2 或 ITS 区域则需要两步消化。根据常规表型鉴定，伊朗临床样本中红色毛癣菌的流行率似乎高于预期。
