Shokohi T, Afshar P, Barzgar A
Department of Medical Mycology and Parasitology, Sari Medical School, Sari, Iran.
Indian J Med Microbiol. 2009 Oct-Dec;27(4):321-4. doi: 10.4103/0255-0857.55445.
Malassezia yeasts are globally distributed agents of pityriasis versicolor and are implicated in the pathogenesis of seborrhoeic and atopic dermatitis. The aim of this study is to identify the Malassezia species obtained from pityriasis versicolor patients, using morphological, biochemical, physiological as well as Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) methods.
The identification of Malassezia species is performed according to microscopic features and physiological characteristics, including catalase reaction and Tween assimilation tests. The DNA is extracted from cultured Malassezia using the glass bead, phenol-chloroform method. The internal transcribed spacer 1(ITS1) region is amplified and there is restricted digestion of the PCR products with two enzymes Cfo I and Bst F5I.
The most commonly isolated species is M. globosa (47.6%). RFLP analysis of the PCR products of the ITS1 region is in complete agreement with those from the DNA sequences of the internal transcribed spacer (ITS) 1 region and the biochemical tests.
Based on the findings of this study, it can be concluded that PCR-RFLP is a relatively simple and quick method, completely comparable to the routine methods used for Malassezia identification.
马拉色菌酵母是全球分布的花斑癣病原体,与脂溢性皮炎和特应性皮炎的发病机制有关。本研究的目的是使用形态学、生化、生理学以及聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法,鉴定从花斑癣患者中分离出的马拉色菌种类。
根据显微镜特征和生理特征,包括过氧化氢酶反应和吐温同化试验,对马拉色菌种类进行鉴定。使用玻璃珠、酚-氯仿法从培养的马拉色菌中提取DNA。扩增内部转录间隔区1(ITS1)区域,并用两种酶Cfo I和Bst F5I对PCR产物进行限制性消化。
最常分离出的菌种是球形马拉色菌(47.6%)。ITS1区域PCR产物的RFLP分析与内部转录间隔区(ITS)1区域的DNA序列分析及生化试验结果完全一致。
基于本研究结果,可以得出结论,PCR-RFLP是一种相对简单快速的方法,与用于马拉色菌鉴定的常规方法完全可比。