都柏林念珠菌的鉴定及与白念珠菌3种表型鉴别方法的研究  

Comparison of three phenotypic approaches with a PCR test to discriminate Candida dubliniensis from Candida albicans isolates

作　　者：徐永豪[1] 李春阳[1] 

机构地区：[1]山东大学齐鲁医院皮肤科,济南250012

出　　处：《中国真菌学杂志》2006年第1期12-15,共4页Chinese Journal of Mycology

基　　金：国家自然科学基金资助项目(C030116)

摘　　要：目的从临床分离的念珠菌中进一步鉴定都柏林念珠菌,并评价3种表型鉴别白念珠菌和都柏林念珠菌的方法。方法对17株临床分离并初步鉴定的白念珠菌和1株ATCC白念珠菌标准株,采用PHR1同源序列PCR法检测,鉴定出其中的都柏林念珠菌;分别采用45℃生长试验、YEPD(1%酵母浸膏,2%蛋白胨,2%葡萄糖)液基39℃芽管生成试验、Staib琼脂(鸟食琼脂)厚壁孢子形成试验对两种菌的表型特点进行比较。结果17株临床分离的白念珠菌中有3株鉴定为都柏林念珠菌;45℃时,两种菌在改良沙堡弱琼脂上均无明显生长,YEPD液基中仅有1株白念珠菌生长良好;YEPD液基39℃培养2种菌均无芽管生成;Staib琼脂培养72h,3株都柏林念珠菌中有2株可形成厚壁孢子,而白念珠菌则无,与PHR1同源序列检测结果基本一致。结论PHR1同源序列检测是鉴别都柏林念珠菌与白念珠菌的可靠方法,Staib琼脂厚壁孢子形成试验有助于鉴别两菌,45℃生长试验和YEPD液基39℃芽管生成试验则不能有效鉴别两菌。Objective To identify Candida dubliniensis from the initial isolates of Candida spp. and to compare three phenotypic approaches for differentiating it from C.albicans.Methods One ATCC type strain of C. albicans and 17 clinical isolates that were identified as C. albicans through routine laboratory methods were collected. Their homologous sequences of PHR1 were amplified with PCR to identify C. dubliniensis in them. We also approached growth test at 45℃, germ tube formation test in YEPD medium at 39℃ and chlamydospore formation test on Staib agar respectively to compare these two fungi’s phenotypic characteristics.Results There were 3 out of the 17 isolates identified as C. dubliniensis. At 45℃, neither the 17 isolates nor the type strain was observed to form obvious colony on modified Sabouraud's agar, and only one C. albicans grew well in YEPD. No germ tube was observed in YEPD medium at 39℃. After cultured on Staib agar for 72 hs, 2 of the 3 C. dubliniensis formed chlamydospore while no C. albicans did. It is partially same with the result of PCR.Conclusions PCR of homologous sequences of PHR1 is a reliable method to discriminate C. dubliniensis from C. albicans. Chlamydospore formation test on Staib agar can be helpful, but growth test at 45℃ or germ tube formation test at 39℃ is not advisable.

关 键 词：都柏林念珠菌 白念珠菌 鉴别 

分 类 号：R379.4[医药卫生—病原生物学]