鲟源荧光假单胞菌的分离鉴定及药敏特性分析

Isolation, identification and antibiotic sensitivity of pathogenic Pseudomonas fluorescens from sturgeons

从患病鲟体内分离到1株细菌,通过形态学观察、生理生化特性鉴定、16SrRNA基因序列分析及系统进化树构建等方法对分离菌种属进行确定,采用纸片扩散法对分离菌进行药物敏感性分析。结果显示:分离菌为革兰阴性杆菌;可分解葡萄糖和木糖,氧化酶和鸟氨酸脱羧酶试验阳性;16SrRNA基因测序分析与荧光假单胞菌(Pseudomonas fluorescens)同源性大于99%,在系统发育树上与荧光假单胞菌聚为一枝;药敏结果显示,分离菌对氧氟沙星、多西环素、复方新诺明等敏感,对氟苯尼考、卡那霉素、阿莫西林等耐药;人工感染试验结果显示,该菌对小鼠有致病力。本研究为贵州地区鲟细菌性疾病预防及合理用药提供依据。

The present study was to identify the bacteria isolated from sturgeon and to analyze their antibiotic sensitivity. A strain of bacteria, GZZY2018, was isolated from the diseased mites, and the isolates were identified by morphological observation, physiological and biochemical characterization, 16 S rRNA gene sequence analysis and phylogenetic tree construction, analysis of drug sensitivity of isolates by antibiotic sensitivity test. The results showed that GZZY2018 was Gram-negative bacilli, which decomposes glucose and xylose, and their oxidase and ornithine decarboxylase were positive. Sequencing analysis of the 16 S rRNA gene showed its homology with Pseudomonas fluorescens was over 99%, and the gene clustered with P. fluorescens in the phylogenetic tree. The antibiotic sensitivity test showed that the strain GZZY2018 was sensitive to ofloxacin, doxycycline and compound neotamine, but was resistant to florfenicol, kanamycin and amoxicillin. The artificial infection test showed that the bacteria was pathogenic in mice.