大熊猫源酵母菌的分离鉴定

摘要

In order to investigate species and genus distribution of yeast on hairs of giant panda and their pathogenicity on mice,thirty-seven hair samples of giant panda were collected and 45 isolates of yeast were isolated from the samples with traditional microbial isolation method.PCR amplification on the strains using the universal fungi primer of ITS1 and ITS4 and phylogenetic analysis were performed.And the 45 isolates belonged to 12 species.Drug sensitive qualitative test of 12 species of yeast were researched using 5 kinds of clinical commonly antifungal medicines by the Danish Rosco disc diffusion method.The results indicated that 12 species of yeast were isolated,including Trichosporon cutaneum,Trichosporon monilii f orme,Trichosporon interdigitale,Trichosporon akiyoshidainum,Trichosporon asteroids,Trichosporon brassicae,Trichosporon guehoae,Trichosporon jirovecii,Trichosporon montevideense,Trichosporon sp.,Candida catenulate and Cryptococcus fragicola.Most of the yeast strains were sensitive to 5 kinds of antifungal drugs.C.fragicola was resistant to ketoconazole,C.catenulate and T.interdigitale were resistant to amphotericin B,C.catenulate and T.jirovecii were resistant to itraconazole,Trichosporon sp.was resistant to fluconazole,C.catenulate,T.interdigitale,T.guehoae and T.cutaneum were resistant to nystati.T.cutaneum,T.interdigitale,T.asteroids,C.fragicola were pathogenic to mice,and other isolates of yeasts were opportunistic pathogenicity.Various yeast species exist in surface of giant panda,and they have different drug sensitivity to fungicides.These results have greatly enriched the understanding of the yeast on hair of giant panda,will provide a reference for the dermatomycoses diagnosis and treatment of giant panda.%旨在调查大熊猫体表酵母菌种属及其对小鼠的致病性.通过传统分离培养、形态学观察,并利用真菌ITS序列通用引物ITS1、ITS4对分离株进行PCR扩增和系统发育学分析,从而鉴定其种属.利用丹麦Rosco纸片扩散法,用两性霉素B、制霉菌素、酮康唑、氟康唑、伊曲康唑对12种分离株进行药敏试验和耐药性分析,同时进行动物致病性试验.结果本次共在37个熊猫被毛样本中分离到45株酵母菌,分属于3个属,12个种.酵母分离菌分别为毛孢子菌属(Trichosporon)40株,隐球菌属(Cryptococcus)4株,假丝酵母菌属(Candida)1株,分别鉴定为皮肤毛孢子菌(Trichosporon cutaneum)、串珠毛孢子菌(Trichosporon moniliiforme)、指间毛癣菌(Trichosporon interdigitale)、秋吉台毛孢子菌(Trichosporon akiyoshidainum)、星形毛孢子菌(Trichosporon asteroids)、芸苔毛孢子菌(Trichosporonbrassicae)、辜氏毛孢子菌(Trichosporonguehoae)、耶氏毛孢子菌(Trichos poron jirovecii)、蒙得维的亚毛孢子菌(Trichosporon montevideense)、毛孢子菌(Trichosporon sp.)、链状假丝酵母菌(Candida catenulate)和长莓隐球酵母(Cryptococcus fragicola),共12种酵母菌.动物致病性试验结果表明:皮肤毛孢子菌、指间毛癣菌、星形毛孢子菌和长莓隐球菌对小鼠致病,其余对小鼠条件致病.多数菌种对5种抗真菌药物敏感,其中长莓隐球酵母对酮康唑耐药;链状假丝酵母菌、指间毛癣菌对两性霉素B耐药;链状假丝酵母菌、耶氏毛孢子菌对伊曲康唑耐药;毛孢子菌(Trichosporon sp.)对氟康唑耐药;皮肤毛孢子菌、指间毛癣菌、辜氏毛孢子菌和链状假丝酵母菌对制霉菌素耐药.大熊猫体表酵母菌种类丰富,各种属对常用抗真菌药物敏感性存在差异.本研究丰富了对大熊猫源酵母菌种群的认识,为大熊猫酵母菌病的诊治提供参考.