Identification of Medically Relevant Molds by Sequence Analysis of the Internal Transcribed Spacer Regions 1 and 2

• Main Authors: Liyin Huang, 黃莉媖
• Other Authors: Hsien-Chang Chang
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/14353691388672741101

碩士 === 國立成功大學 === 醫學工程研究所 === 91 === The frequency of fungal infections has increased in recent years due to the increasing number of immunocompromised patients. Rapid identification of clinically relevant molds is useful for appropriate treatment with antifungal agents. The conventional methods for fungal identification mostly rely on morphological and biochemical tests; these methods are time-consuming and may be inaccurate. In this study, the feasibility of identification of medically important fungi by using the sequences of the internal transcribed spacer regions 1 and 2 (ITS1 and ITS2) was evaluated. The ITS data in GenBank were insufficient to identify clinically relevant fungi. The ITS1 and ITS2 regions from 198 reference strains (69 species) were amplified by PCR and sequenced; these sequences in combination with data in the GenBank were used to construct an ITS sequence database for the identification of molds. Totally 110 ITS1 and 108 ITS2 sequences were determined in this study. It was found that the ITS similarity scores among strains of the same species usually exceeded 0.95, whereas the scores were less than 0.95 among different species. The database was used to test 70 strains (30 species) of clinical isolates; a sensitivity of 89% and a specificity of 90% were obtained. It was concluded that the present method provides a rapid, simple, and reliable alternative to conventional methods for identification of medically important molds.