摘要
目的建立常见病原假丝酵母菌种间分型和对白色假丝酵母菌种内基因分型的方法,并分析白色假丝酵母菌不同基因型与耐药表型的关系。方法采用PCR技术扩增假丝酵母菌r DNA的内转录间隔区ITS1-ITS2,根据PCR产物片段的大小进行假丝酵母菌种间分型;采用特异引物扩增白色假丝酵母菌基因组DNA的25S r DNA基因的内含子区,以内含子大小及其中可转座I型内含子片段的缺失或插入作为分型依据,对白色假丝酵母菌进行种内基因分型。并对肺癌患者感染的白色假丝酵母菌不同基因型的耐药性进行分析。结果依据科玛嘉显色培养基结果和PCR电泳图谱,与基因库中假丝酵母菌基因序列比对,分为四种:白色假丝酵母菌242株大小218 bp,光滑假丝酵母菌101株大小480 bp,热带假丝酵母菌49株大小219 bp,克柔假丝酵母菌16株大小150 bp。临床分离的242株白色假丝酵母菌经PCR方法分为3型:A型166株(450 bp),B型54株(840 bp),C型22株(450、840 bp)。A型为最常见的基因型,B型、C型白色假丝酵母菌对唑类抗真菌药物的耐药率显著高于A型菌株(P<0.05),对其他抗真菌药物的耐药率差异无统计学意义。结论 PCR方法用于假丝酵母菌种间与种内的分型具有较高的灵敏性与特异性,不同型的白色假丝酵母菌耐药性可能与特定基因型有一定相关性。
Objective To establish method of interspecific classification of common pathogenic Candida and intraspecific identification of Candida albicans, and explore the relationship between the genotypes and drug resistance phenotype of Candida albicans. Methods Internal transcribed spacer region ITS1-ITS2 of Candida albicans r DNA was amplified by PCR; Candida interspecies were typed according to the size of PCR fragment. Intron of 25 S r DNA gene of Candida albicans was PCR amplified from genomic DNA by specific primers for intraspecific genotyping. Drug resistance of different genotypes of Candida albicans isolated from lung cancer patients was analyzed. Results Candida was divided into four types according to the results of CHROMagar and PCR electrophoresis,and compared with Candida gene sequence of the gene pool. 242 strains of Candida albicans,218 bp; 101 strains of Candida glabrata, 480 bp; 49 strains of Candida tropicalis, 219 bp; 16 strains of Candida krusei,150 bp. 242 strains of Candida albicans clinical isolates were divided into three types by PCR ： 166 strains of A（450 bp）, 54 strains of B（840 bp）, and 22 strains of C（450bp, 840 bp）. Type A is the most common genotype; B and C types of Candida albicans were significantly moreresistant to azole antifungal drugs than those of A type. There was no significant difference in the rate of resistant to other antifungal drugs. Conclution The PCR method has higher sensitivity and specificity for interspecific and intraspecific typing of Candida.Resistance of different Candida albicans can be associated with a particular genotype.
出处
《热带医学杂志》
CAS
2015年第9期1174-1177,共4页
Journal of Tropical Medicine
基金
2014年河北省卫生厅医学科学研究重点课题计划项目(ZD20140122)
