通过FtsZ纤维的磨驱动糖合成和细菌细胞分裂
Alexandre W Bisson-Filho1, Yen-Pang Hsu2, Georgia R Squyres1
1Molecular and Cellular Biology, Faculty of Arts and Sciences Center for Systems Biology, Harvard University, Cambridge, MA 02138, USA.
Science (New York, N.Y.)
|February 18, 2017
概括
细菌细胞分裂依赖于FtsZ和FtsA (FtsAZ) 纤维. 这些纤维环绕地运行,指导细胞壁结构和分裂的糖合成.
科学领域:
- 微生物学
- 细胞生物学
- 生物化学
背景情况:
- 细菌细胞分裂是一个基本的过程,对于微生物的生长和生存至关重要.
- 细胞运动的确切机制,特别是细胞壁合成的协调,仍然不完全理解.
- 已知FtsZ和FtsA (FtsAZ) 的细丝通过招募必需酶来调解细胞分裂.
研究的目的:
- 阐明FtsAZ纤维和细菌细胞动因过程中的糖合成之间的动态协调.
- 了解FtsAZ组件的运动如何影响细胞壁形成的空间和时间调节.
- 确定FtsZ导线动态在控制细胞分裂速度中的作用.
主要方法:
- 使用活细胞成像技术可视化FtsAZ纤维和糖合成部位的运动.
- 使用高分辨率显微镜实时跟踪细胞分裂过程中的这些成分的动态.
- 进行了丝流程速率的定量分析及其与细胞壁合成的相关性.
主要成果:
- 分离隔膜是在分离平面内呈现动态运动的离散部位上组装的.
- FtsAZ 纤维在分裂环周围经历环形跑步板,积极指导糖合成酶的运动.
- 确定FtsZ步行速度是糖合成速度和细胞分裂速度的关键决定因素.
- 这种缓冲作用导致同心糖环的渐进合成,使细胞收缩.
结论:
- FtsZ跑步机是一个关键的机制,在空间和时间上协调细菌细胞壁的合成过程.
- FtsAZ纤维的动态运动为细胞壁合成机器的招募和指导提供了物理轨道.
- 了解FtsZ跑步机提供了细菌细胞运动的基本过程和抗菌策略的潜在目标.
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