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在FliI ATPase配对ATP水解到基质切换的细菌鞭毛型III分泌物
Rosa Einenkel1, Caroline Kühne1, Mario Delgadillo-Guevara1,2
1Humboldt-Universität zu Berlin, Institute of Biology, Berlin, Germany.
mBio
|December 5, 2025
概括
细菌鞭毛组合需要精确控制基质出口. ATPase FliI对于在早期和晚期分泌阶段之间切换至关重要,确保有序的鞭毛结构.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 细菌鞭毛组件依赖于III型分泌系统 (T3SS) 进行结构子单元的订购出口.
- 已知ATPase FliI在T3SS中激活基质转位,但其在调节分泌阶段过渡中的作用尚不清楚.
研究的目的:
- 调查FliI ATPase活性在控制鞭毛组装期间早期和晚期基质出口之间的过渡中的作用.
- 阐明FliI的ATPase功能与T3SS中的基质切换之间的机械联系.
主要方法:
- 对具有在FliI.I.催化领域突变的Salmonella enterica菌株进行系统分析.
- 基质出口的评估,基体的形成,来自3类促进者的基因表达和鞭毛丝组合.
- 评估FliI局部化和寡合化.
主要成果:
- 最小的FliI ATPase活性支持早期基质出口和基体形成.
- 有效的基质特异性切换和晚期基质出口需要接近野生类型的FliI ATPase活性.
- 突变菌株表现出延迟的3类促进体表达,延长的早期分泌和受损的鞭毛组合.
结论:
- FliI ATPase活动对于控制鞭毛组合的时间动态至关重要.
- FliI在T3SS中发挥着多方面的作用,有助于基底切换并确保强大的鞭毛生物发生.
- 这项研究确定了ATPase活性和T3SS中的基质切换之间的机制联系.
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