一株临床分离的欧洲放线菌的鉴定及生物学特性研究

Identification and biological characteristics of an Actinomyces europaeus strain

目的探讨欧洲放线菌的鉴定方法、生物学特性,为放线菌病的诊断提供依据。方法取患者的脓液标本,进行细菌培养及革兰染色检查,用VITEK 2 Compact全自动微生物分析仪进行鉴定,E-test法作药敏试验。基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)进行分离株的鉴定。提取菌株的DNA,选用16S rRNA的通用引物进行扩增,回收、纯化后对PCR的产物进行测序,与GenBank数据库中的序列进行同源性比较。结果药敏试验结果为对青霉素、哌拉西林/他唑巴坦、头孢曲松敏感,对环丙沙星耐药。MALDI-TOF MS鉴定为欧洲放线菌。16S rRNA基因检测鉴定为欧洲放线菌。结论MALDI-TOF MS和16S rRNA可对欧洲放线菌进行鉴定,对放线菌病的诊断具有重要的意义。

Objective To investigate the methods for identifying Actinomyces europaeus and to analyze its biological characteristics in order to provide a basis for the diagnosis of actinomycosis.Methods Pus specimens collected from patients were used for bacterial culture and then analyzed with Gram staining.VITEK 2 Compact automatic microbiological analyzer was used for species identification.Drug susceptibility test was performed with E-test.Matrix-assisted laser desorption/ionization-time of flight mass spectrometry(MALDI-TOF MS)was used to identify the isolated strain.The common primers of 16S rRNA were used for amplification following DNA extraction,and the product of PCR was sequenced after recovery and purification.Homology analysis was conducted using the sequence in GenBank database.Results The drug susceptibility test showed that the strain was sensitive to penicillin,piperazolin/taclobatan,and ceftriaxone,but resistant to ciprofloxacin.MALDI-TOF MS and 16S rRNA gene assay identified the strain as Actinomyces europaeus.Conclusions MALDI-TOFMS and 16S rRNA could be used to identify Actinomyces europaeus and are of great significance for the diagnosis of actinomycosis.