一株马脲片球菌的分离、鉴定及其部分16S rDNA基因序列测定

目的对门诊分离出一株α溶血的革兰阳性球菌（命名为NC588）进行鉴定。方法对NC588进行基本形态观察、生化反应分析和部分16S rDNA测定。结果该菌多数呈双排列,少见单个或链状,无动力,无荚膜,直径为1.2～2.0μm;发酵葡萄糖产酸不产气,触酶和氧化酶阴性,不还原硝酸盐;可生长pH为3.5～7.5,最适pH为6.0～6.5;15℃和45℃不生长,20～40℃生长良好;35℃普通气体条件下培养24h见菌落呈针尖样,48℃后出现α溶血。高度耐糖肽类抗生素,对万古霉素和替考拉宁MIC值分别为256、128μg/mL。部分16S rDNA序列测定和同源性分析显示,NC588与马脲片球菌的同源性为100%。结论NC588鉴定为马脲片球菌。

Isolation,Identification and Partial 16S rDNA Sequence Analysis of a Strain Pediococcus Urinaeequi

Objective A strain a hemolysis Gram-strain positive coccus,named NC588,was isolated from the outpatient department, and then identify it. Methods Basically bacterial form, biochemical reaction and partial 16S rDNA were examined for NC588. Results it was most diplococci,least single or streptococcus, no motion and capsule. The size of bacteria was about 1. 2 2.0 μm and glucose could be utilized to produce acid but no gas, no eatalase and oxidase, and never utilize natrate;it could grow at pH 3.5-7.5 ,and the best pH was 6.0-6.5. There was no growing at 15 ℃ and 45 ℃ ,but could grow well at 20-40 ℃. After 24 h culture at 35 ℃ in common air,a needle-like colony showed up and a hemolytic phenomenon after 48 ℃ was determined. It was high resistance to glypeptide antibiotics,and the MIC of resist vancomycin was 256 μg/mL and teicoplanin was 128μg/mL each. NC588 has 100% homologous to Pediococcus Urinaeequi by partial 16S rDNA sequences. Conclusion NC588 is Pediococcus Urinaeequi.