用聚合酶链反应和限制性内切酶技术快速鉴定医学真菌

Rapid identification of medically important fungi using molecular biological method

介绍了一种基于聚合酶链反应（ＰＣＲ）结合限制性内切酶分析技术区分临床重要真菌的方法。首先利用９种真菌的通用引物扩增其１８ＳｒＲＮＡ基因，然后用ＨａｅⅢ、ＢｇｌⅠ和ＮｈｅⅠ三种限制性内切酶将扩增产物消化成不同数量和不同大小的ＤＮＡ片段，可以对白色念珠菌、新型隐球菌和烟曲霉菌等９种临床上常见的医学真菌作出快速鉴定。该技术具有快速、敏感、不需杂交、可在２４ｈ以内完成鉴定等优点，有良好的临床应用前景。

The methods of identification of medically important fungi to the species level currently used are examination of morphology or determination of biochemical characteristics. Both methods require the presence of viable fungi and are insensitive. In this paper,a rapid method for identifying 9 species of medically important fungi (Candida albicans, C. tropicalis, C. kefyr, C. parapsilosis, Torulopsis glabrata, C. lipolytica, Cryptococcus neoformans, Aspergillus fumigatus, A. flavus) using the polymerase chain reaction (PCR) and restriction enzyme analysis is described. The primers we designed amplified the 621-687 bp fragments of the 18 S rRNA gene of 9 fungal species. The PCR products were then digested by HaeⅢ, BglⅠ and NheⅠ. The 9 species of fungi mentioned above can be differentiated to the species level. It is a rapid and sensitive method, which does not involve hybridization steps or radioactivity, and the identification can be completed within one day.