【摘要】 目的应用基因测序方法对2株疑似非结核分枝杆菌的菌株进行初步菌种鉴定,指导临床用药治疗。方法将2株临床分离菌株1520、4108分别接种于罗氏培养基,观察其菌落生长状况;取生长对数期菌落,抽提菌株DNA;PCR扩增16SrDNA基因序列,对其PCR产物进行测序和NCBI网站Blast同源性比对,以进行菌株的初步鉴定。结果编号为1520、4108两株菌株,在罗氏培养基上生长迅速,均可见淡黄色粗颗粒样小菌落,疑似非结核分枝杆菌;以PCR扩增两株菌的16SrDNA基因序列,结果与鼻疽诺卡菌(Nocardia farcinica)同源性极高,比例均达到99%。结论从肺科急诊患者体内分离到的菌株1520、4108为鼻疽诺卡菌,而不是非结核分枝杆菌,为临床在治疗方案上提供了有力的证据。同时,DNA测序分析能够快速、简便、准确地鉴定到菌种,为实验室疑难菌型鉴定提供了技术保障。更多还原

【Abstract】 Objectives To identify species of bacterium by gene sequencing technology so as to guide clinical treatment. Methods Two clinical strains 1520 and 4108 were inoculated on Lowenstein-Jensen medium separately, and the bacteria colonies were observed in logarithmic phase. DNA of the two colonies were extracted, which was used as template for amplification of their 16S rDNA gene by polymerase chain reaction (PCR). Then the amplification products were sequenced and the sequences were blasted on NCBI for the preliminary identification of strains. Results The two strains of No. 1520 and 4108 grew rapidly and formed small coarse granular with light yellow on the Lowenstein-Jensen medium, which was suspected as Nontuberculous Mycobacteria (NTM). The DNA homology of 16S rDNA genes of 1520 and 4108 compared with Nocardia farcinica were 99% respectively. Conclusions Strains of 1520 and 4108 isolated from two patients with pulmonary disease were Nocardia farcinicas, rather than suspected NTM, which provided strong evidence for clinic treatment. In the same time, DNA sequencing analysis is a fast, simple, and accurate way to identify strains of the species.更多还原