【目的】通过分析分离自牛虻体内的螺原体NM1108-1和NM1108-5的基本生物学特性,了解分离菌株可能的分类地位,为进一步研究螺原体与宿主的相互作用提供信息。【方法】运用常规方法分离培养牛虻螺原体,利用暗视野显微镜和透射电镜观察分离菌株的形态特征,结合其生理生化特性及系统发育学特性研究初步确定分离菌株的分类地位。【结果】从牛虻中分离到大量螺原体,以其中两个代表性的菌株NM1108-1和NM1108-5为主要研究材料,在暗视野显微镜下观察其形态均呈螺旋状,做翻滚式运动;两者都能利用葡萄糖、果糖、蔗糖作为碳源,不利用尿素和精氨酸,对四环素比较敏感,对青霉素不敏感;系统发育树显示,分离到的牛虻螺原体菌株NM1108-1和NM1108-5属于Apis一支但属于不同亚支,NM1108-1与S.turonicom聚为一支;NM1108-5与S.gladiatoris聚为一支。【结论】两株牛虻螺原体NM1108-1和NM1108-5的分类地位分别初步被确定为S.turonicom和S.gladiatoris,这是首次报道我国牛虻体内的螺原体。
[Objective] The purpose of this research was to analyze the biological characteristics of isolates NM1108-1 and NM1108-5 obtained from gadfly in China, and to determine the taxonomy of the two isolates. It provided more information about interaction between spiro-plasma and their host. [Methods] The gadfly spiroplasmas were isolated and cultured by con-ventional methods. Dark field and transmission electron microscopy were used to examine the morphology and movement of spiroplasma isolates. The taxonomy of the two isolates was evaluated according to their biological and phylogenetic characteristics. [Results] A large number of spiroplasmas were isolated from gadfly, and two representative strains NM1108-1, NM1108-5 exhibited helical form in logarithmic phase. Both the spiroplasmas from gadfly could use glucose, sucrose and D-fructose as a carbon and resisted to penicillin, but did not hydrolyse urea or arginine. The phylogenetic analysis based on 16S rDNA and ITS sequences showed that both isolates NM1108-1 and NM1108-5 belonged to the Apis clade but were di-vided into two different branches. NM1108-1, NM1108-5 were clustered into S. turonicom, S. gladiatoris respectively. [Conclusion] The isolates of NM1108-1 and NM1108-5 were initially determined as S. turonicom and S. gladiatoris respectively according to their biological and phylogenetic characteristics. This was the first report about the spiroplasmas from gadfly in China.