黄道蚜蝇螺原体的分离及其基本生物学特性

Isolation and characterisation of Spiroplasma sp. from Phytomia zonata (Diptera: Syrphidae)

摘要:

摘要：【目的】调查我国部分昆虫螺原体的存在情况，收集我国的昆虫螺原体资源，并研究它们的基本生物学特性，初步确定其分类地位。【方法】螺原体分离、培养方法，应用暗视野显微镜和透射电子显微镜观察螺原体形态，根据16S rDNA构建系统发育树研究螺原体分离菌株可能的分类地位。【结果】从黄道蚜蝇昆虫体内分离到螺原体YY0801，并对其进行了形态学、基本生物学及分子生物学特性研究。分离菌株在R2液体培养基中生长良好，能通过孔径为0.22 μm、0.45 μm的微孔滤膜；在R2固体培养基上呈颗粒状菌落；在对数期呈典型的螺旋状；能利用葡萄糖、D-果糖作为碳源；能强烈代谢精氨酸；不能利用尿素，在含氨苄青霉素钠(2000 U/mL)的R2液体培养基中生长良好。根据16S rDNA构建的系统发育树显示，分离菌株YY0801与血清组Ⅰ的Spiroplasma melliferum 聚类较近。【结论】首次在国内从食蚜蝇科中的黄道蚜蝇（Phytomia zonata）分离到螺原体，分离菌株YY0801可能是Spiroplasma melliferum，但其确切的分类地位需要进行血清学进一步分析。

Abstract:

Abstract: [Objective] To obtain the spiroplasma resources and characterize the spiroplasmas from insects in China, as well as study the taxonomy of spiroplasma based on biological characteristics. [Methods] We determined morphology by using dark field and transmission electron microscopy. The biological characteristics of the spiroplasmas were studied by using conventional culture-dependent method and phylogenetic analysis based on 16S rDNA. [Results] Based on morphological characteristics, biological characteristics and phylogenetic evidences, we studied the taxonomy of the strain YY0801 isolated from Phytomia zonata (Diptera: Syrphidae). The isolate grew well in R2 liquid medium and could pass through 0.22 μm and 0.45 μm filtrate membranes. The colony was grain-like in solid medium. Through electron microscopy, the isolate YY0801 exhibited helicity during their exponential growth phase. The isolate YY0801 was able to ferment glucose and D-fructose and to catabolize arginine, but did not to hydrolyse urea. The isolate was resistant to ampicillin (2000 U/mL). The phylogenetic relationships based on 16S rDNA supported YY0801 grouped with the serogroupⅠand was close to S. melliferum. [Conclusion] The result indicated that the spiroplasma isolate YY0801 was close to S. melliferum, but further designation need support of serological analyses.