嗜冷酵母属Mrakia中核糖体DNA的IGS和ITS区域的分子分析

Molecular analyses of the IGS & ITS regions of rDNA of the psychrophilic yeasts in the genus Mrakia.

作者信息

Diaz M R, Fell J W

机构信息

Rosenstiel School of Marine and Atmospheric Science, University of Miami, Key Biscayne, FL 33149 USA.

出版信息

Antonie Van Leeuwenhoek. 2000 Jan;77(1):7-12. doi: 10.1023/a:1002048008295.

DOI:10.1023/a:1002048008295

PMID:10696872

Abstract

Species of the genus Mrakia are currently classified as synonyms based on molecular sequence analyses of the large sub-unit ribosomal DNA (LrDNA). Physiological and protein electrophoretic studies, however, reveal possible species differences. To clarify this discrepancy, we undertook molecular sequence analyses of the internal transcribed spacer (ITS) and intergenic spacer (IGS) regions of rDNA from the four psychrophilic Mrakia species and the psychrophilic yeast, Cryptococcus curiosus. Identical ITS sequences were found between C. curiosus, M. nivalis and M. frigida. Although, M. stokesii and M. gelida displayed identical ITS and IGS sequences, their sequences differed from the other three species by 2.3% and 38%, respectively. The results suggest that M. stokesii is a synonym of M. gelida, whereas M. nivalis is a synonym of M. frigida. Sequence differences (1.9%) observed in the IGS region indicates that C. curiosus is a distinct strain of M. frigida.

摘要

基于大亚基核糖体DNA（LrDNA）的分子序列分析，目前将Mrakia属的物种归类为同义词。然而，生理和蛋白质电泳研究揭示了可能存在的物种差异。为了澄清这一差异，我们对四种嗜冷Mrakia物种和嗜冷酵母Cryptococcus curiosus的核糖体DNA的内部转录间隔区（ITS）和基因间隔区（IGS）进行了分子序列分析。在Cryptococcus curiosus、M. nivalis和M. frigida之间发现了相同的ITS序列。虽然，M. stokesii和M. gelida显示出相同的ITS和IGS序列，但它们的序列分别与其他三个物种相差2.3%和38%。结果表明，M. stokesii是M. gelida的同义词，而M. nivalis是M. frigida的同义词。在IGS区域观察到的序列差异（1.9%）表明Cryptococcus curiosus是M. frigida的一个独特菌株。