牦牛源产气荚膜梭菌青海分离株的生物学特性

Biological Characterization of Clostridium perfringens Qinghai Isolate of Yak Origin

为了解本实验室分离保存的1株牦牛源产气荚膜梭菌qinghai-12分离株的生物学特性,本试验通过多种生物学方法对该菌株的生物学特性进行分析。结果显示:该菌株在葡萄糖、麦芽糖、蔗糖、卵磷脂酶、乳糖、酪蛋白生化鉴定管中呈阳性反应,石蕊牛乳试管中呈现“汹涌发酵”现象;16S rRNA和多重PCR鉴定该菌株为牦牛源C型产气荚膜梭菌;该菌株按1%接种至梭菌增菌培养基,在4~8 h处于对数生长期;10 h为该菌株的最佳产毒时间,含量达4.173 mg/mL;依据16S rRNA遗传进化树分析,该菌株与北京人源(GenBank登录号:KP944154.1)、安多牦牛源(GenBank登录号:MN960262.1)、美国猪源(GenBank登录号:JQ607422.1)、华东兔源(GenBank登录号:KX986316.1)产气荚膜梭菌具有较近的亲缘性;最低抑菌浓度(MIC)测定结果显示,该菌株对头孢噻肟、氨苄西林、四环素、青霉素表现为敏感。本试验通过对牦牛源C型产气荚膜梭菌生物特性的分析,为牦牛源产气荚膜梭菌后续研究及防治等方面提供一定的技术支持。

This study aimed to assess the biological characteristics of Clostridium perfringens(C.perfringens)qinghai-12 isolated and preserved in our laboratory using culture technique,biochemical tests and molecular methods.The results showed that the strain was positive for glucose,maltose,sucrose,lecithin enzyme,lactose and casein in biochemical identification tube,and displayed"stormy fermentation"phenomenon in litmus milk tube.The strain was identified by 16S rRNA and multiple PCR as C.perfringens of yak origin.The strain was inoculated to C.difficile growth medium at 1%and was in logarithmic growth stage at 4-8 h,with 10 h being the best time for the strain to produce toxins(reaching 4.173 mg/mL).The strain was identified by 16S rRNA and multiple PCR as C.perfringens of yak origin.The 16S rRNA genetic evolution tree analysis confirmed its close relationship to C.perfringens Beijing human origin(GenBank accession number:KP944154.1),Amdo yak origin(GenBank accession number:MN960262.1)and American pig origin(GenBank login number:JQ607422.1),and East China rabbit(GenBank accession number:KX986316.1).Minimum inhibitory concentration(MIC)results revealed that the strain was sensitive to cefotaxime,ampicillin,tetracycline and penicillin.Through examination of the biological characteristics of C type C.perfringens from yaks,this study provides guidance for the follow-up research and control of C.perfringens in yaks.