Wang Qi-Ming, Li Juan, Wang Shi-An, Bai Feng-Yan
Systematic Mycology and Lichenology Laboratory, Institute of Microbiology, Chinese Academy of Sciences, Datun Road, Chaoyang District, Beijing 100101, China.
Appl Environ Microbiol. 2008 May;74(9):2604-11. doi: 10.1128/AEM.02223-07. Epub 2008 Mar 14.
Single-strand conformation polymorphism (SSCP) analysis of ribosomal DNA (rDNA) was investigated for rapid differentiation of phenotypically similar yeast species. Sensitive tests indicated that some yeast strains with one, most strains with two, and all strains with three or more nucleotide differences in the internal transcribed spacer 1 (ITS1) or ITS2 region could be distinguished by PCR SSCP analysis. The discriminative power of SSCP in yeast species differentiation was demonstrated by comparative studies of representative groups of yeast species from ascomycetes and basidiomycetes, including Saccharomyces species, medically important Candida species, and phylloplane basidiomycetous yeast species. Though the species within each group selected are closely related and have relatively similar rDNA sequences, they were clearly differentiated by PCR-SSCP analysis of the ITS1 region, given the amplified fragments were less than 350 bp in sizes. By using SSCP analysis for rapid screening of yeast strains with different rDNA sequences, species diversity existing in a large collection of yeast strains from natural sources was effectively and thoroughly investigated with substantially reduced time and cost in subsequent DNA sequencing.
为了快速区分表型相似的酵母菌种，对核糖体DNA（rDNA）的单链构象多态性（SSCP）分析进行了研究。敏感性测试表明，一些在内部转录间隔区1（ITS1）或ITS2区域有一个核苷酸差异的酵母菌株、大多数有两个核苷酸差异的菌株以及所有有三个或更多核苷酸差异的菌株，都可以通过PCR-SSCP分析加以区分。通过对来自子囊菌门和担子菌门的代表性酵母菌种进行比较研究，包括酿酒酵母属菌种、医学上重要的念珠菌属菌种以及叶表担子菌酵母菌种，证明了SSCP在酵母菌种区分中的鉴别能力。尽管所选每组中的菌种亲缘关系密切且rDNA序列相对相似，但鉴于扩增片段大小小于350 bp，通过对ITS1区域进行PCR-SSCP分析，它们能够被清晰区分。通过使用SSCP分析快速筛选具有不同rDNA序列的酵母菌株，有效地、全面地研究了来自自然来源的大量酵母菌株中存在的物种多样性，同时大幅减少了后续DNA测序的时间和成本。
