蜜蜂螺原体南京分离株M10形态的多样性

Morphological polymorphy of spiroplasmas isolated from honeybee in Nanjing

为进一步了解蜜蜂螺原体的生长、生殖及致病特点,以分离自患"爬蜂病"蜜蜂体内的螺原体菌株M10为研究对象,测定了其生长曲线,利用透射电镜观察其不同生长期的形态。结果表明:在R-2培养基中,不同生长期的蜜蜂螺原体M10形态差异很大,但其形态变化又具有一定的规律性。延滞期的M10以粗短的形态为主;在对数期和稳定期,M10具有丰富的形态多样性,如芽状、分支状、串珠状等;到达衰亡期,M10则变得细长,菌体自身及菌体之间极易缠绕并聚集成团。此外,观察到M10具有尖端结构和纤毛状结构,大多数菌体具有"一尖一圆"结构,纤毛状结构长度差异显著。本研究首次描述了不同生长期蜜蜂螺原体的形态变化,发现螺原体纤毛状结构最长可达1 860.5 nm,并首次在人工培养基中发现螺原体具有类似纤毛接合现象。

To clarify spiroplasmas growth, division and pathogenicity, the growth curve of spiroplasmas isolated from honeybee infected by spiroplasma MIO was determined and the morphology of different growth stages were observed by transmission electron microscopy with negative-staining method. The result showed that abundantly polymorphic forms of M10 were observed in liquid culture medium R-2 with aging. M10 appeared wide and short during the lag phase. During the exponential and stationary phases, M10 showed abundant polymorphy such as bud-shaped, branched, bead-like, while became long and congregated in the death phase. Additionally, the tip structures and pili-like structures were also examined, most helices possessed one tip structure and one blunt end. The length of pili-like structures varied significantly and the longest was 1 860. 5 nm. For the first time, the morphological polymorphy of spiroplasmas isolated from honeybee on all growth stages,were studied, and the phenomenon of conjugating like between two microbes in vitro was existed.