一种复发性发烧细菌的血流与相关的变种
1Laboratory of Microbial Structure and Function, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA. tom_schwn@nih.gov
概括
复发性发烧螺旋体Borrelia hermsii在哺乳动物和宿主之间交换其表面蛋白质 (Vmps). 这种表型转换是取决于温度和可逆的,有助于宿主适应.
科学领域:
- 微生物学 微生物学
- 寄生虫学的寄生虫学
- 载体传播疾病 载体传播疾病
背景情况:
- 博雷利亚 (Borrelia hermsii) 是一种复发性发烧螺旋体,在哺乳动物宿主和媒介之间循环.
- 了解宿主相关的表型变化对于理解病原体传播和生存至关重要.
研究的目的:
- 调查Borrelia hermsii在不同宿主中的生命周期期间是否经历表型变化.
- 确定参与宿主适应和调节的特定表面蛋白质.
主要方法:
- 从受感染的小鼠中感染Borrelia hermsii (血清型7或8) 的Ornithodoros hermsi.
- 在和小鼠中监测螺旋体变量主要蛋白 (Vmps) 的变化.
- 通过改变温度在体外诱导表型开关.
主要成果:
- 在感染后,Borrelia hermsii降低了特定于血清型的Vmps (7或8) 和上调的Vmp33.
- 这种转换为与相关的表型可以通过降低温度在培养物中复制.
- 回到小鼠的传播逆转了这一过程,螺旋体恢复了它们最初的Vmps的表达.
结论:
- 博雷利亚 hermsii 呈现宿主依赖的表型可塑性,在哺乳动物和宿主之间切换Vmp表达.
- 温度是一个关键的环境提示调节这个Vmp开关,促进适应向量.
- 这种表型变化的可逆性突出显示了螺旋细胞对传播的适应性.
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