摘要
为了研究蜱源性粪肠球菌的生长条件及致病性,试验从草原革蜱体内分离出细菌,然后对分离菌进行革兰氏染色、生化鉴定、溶血试验、16S rRNA基因序列分析及构建系统进化树、药敏试验,最后通过小鼠致病性试验验证分离菌的致病性。结果表明:分离菌在普通营养琼脂培养基上培养可见光滑、湿润、呈灰白色微凸状、边缘整齐的露珠状小菌落;革兰氏染色镜检为阳性菌;分离菌可发酵麦芽糖、葡萄糖、乳糖、甘露醇和蔗糖,西蒙氏枸橼酸盐试验及吲哚试验结果均为阳性,明胶试验及氧化酶试验结果均为阴性。分离菌16S rRNA基因序列与GenBank中粪肠球菌(登录号为CP018102.1)的相似性达99%以上;分离菌对环丙沙星敏感,对卡那霉素、庆大霉素、红霉素及头孢噻肟耐药;分离菌在血琼脂培养基上呈现α溶血,但是对昆明小鼠无明显致病性,小鼠各实质脏器无任何肉眼可见的病理变化。说明分离菌为粪肠球菌,仅对抗生素环丙沙星敏感,并无明显致病性。
In order to study the growth condition and pathogenicity of tick-derived Enterococcus faecalis,in the experiment,Dermacentor nuttalli was used as the test material.The bacteria were isolated from the tick;then the isolate was subjected to Gram staining,biochemical identification,hemolysis test,16S rRNA gene sequence analysis and construction of phylogenetic tree,and drug sensitivity test;finally,the pathogenicity of the isolate was verified by mouse pathogenicity test.The results showed that the isolate was cultured on normal agar nutrient medium,which showed smooth and moist,grayish-white micro-convex,neatly edged dewdrop-like colonies;Gram staining microscopy was positive;the isolate could ferment maltose,glucose,lactose,mannitol and concanavalin;Simon's citrate test and indole test results were positive;gelatin test and oxidase test results were negative.The 16S rRNA gene sequence of the isolate showed 99%similarity to that of Enterococcus faecalis(accession no.CP018102.1)in GenBank;the isolate was sensitive to ciprofloxacin,and resistant to kanamycin,gentamicin,erythromycin and cefotaxime;the isolate showedα-hemolysis on blood agar medium,but it was not obviously pathogenic to Kunming mice,and there were no pathological changes in the parenchymal organs visible to the naked eye.The results suggested that the isolate was characterized as Enterococcus faecalis,which was only sensitive to the antibiotic ciprofloxacin and was not obviously pathogenic.
作者
满达
敖晓芳
策勒木格
格日勒图
MAN Da;AO Xiaofang;Ceemuge;Gerietu(College of Animal Science,Inner Mongolia Agricultural University,Hohhot 010018,China;College of Veterinary Medicine,Inner Mongolia Agricultural University,Hohhot 010018,China)
出处
《黑龙江畜牧兽医》
CAS
北大核心
2024年第11期67-71,120,共6页
Heilongjiang Animal Science And veterinary Medicine
基金
内蒙古自治区自然科学基金项目(2021MS03047)
2022年动物科学学院高水平成果培育专项(XSCX202201)。
关键词
草原革蜱
粪肠球菌
分离
鉴定
小鼠
致病性
Dermacentor nuttalli
Enterococcus faecalis
isolation
identification
mice
pathogenicity
