通过FlhF和FlhG控制Helicobacter pylori中的鞭毛模式
Katherine H Gibson1, Jack M Botting1, Natalie Al-Otaibi2
1Department of Microbiology, University of Georgia , Athens, Georgia, USA.
Journal of bacteriology
|September 1, 2023
概括
FlhG调节鞭毛细胞数量,而FlhF对于鞭毛细胞组合和Helicobacter pylori的极地定位至关重要. 一种FliF变体有助于在没有FlhF的情况下形成MS环,支持FlhF在这个过程中的作用.
科学领域:
- 微生物学 微生物学
- 细菌生理学 细菌生理学
- 分子生物学分子生物学
背景情况:
- 杆菌利用鞭毛进行运动,这对于殖民人类的胃是必不可少的,并引起诸如胃潰瘍和胃癌等疾病.
- 众所周知,FlhF和FlhG是许多细菌中鞭毛数量和局部性的调节者,但它们在H. pylori等多鞭毛物种中的特定作用不太清楚.
研究的目的:
- 调查FlhF和FlhG在Helicobacter pylori鞭毛调节中的功能.
- 为了描述缺乏flhF或flhG的H. pylori突变体的鞭毛模式和运动性.
- 鉴定有助于鞭毛状细胞聚集和局部化的遗传因素,特别是在没有FlhF的情况下.
主要方法:
- 对H. pylori的基因删除突变 (ΔflhG, ΔflhF) 进行了构建和分析,以确定鞭毛细胞数量和定位.
- 运动性测定是在野生型和突变菌株上进行的.
- 分离了 ΔflhF 突变的移动变体,并选了基因变异.
- 在体外组装试验中,使用复合野生类型和突变的FliF蛋白进行了测试.
主要成果:
- 删除flhG导致每个细胞的鞭毛细胞数量分布更广泛.
- 删除flhF导致运动性降低,鞭毛细胞减少,鞭毛细胞不适当地定位到非极点.
- 一种带有fliF误解突变的运动型ΔflhF变异 (FliFN255D) 显示了鞭毛细胞局部化的改善和鞭毛细胞生产的增加.
- 再组合的FliFN255D在体外形成了环状结构,这表明在没有FlhF的情况下增强了MS环组装.
结论:
- FlhG有助于保持H. pylori. 每个细胞的标数量的一致.
- FlhF对于适当的鞭毛组合和极地定位至关重要,可能是通过促进MS环的形成.
- 这种FliFN255D变体表明MS环组装可以独立于FlhF发生,支持FlhF作为早期鞭毛组装步骤的促进者的作用.
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