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Biophysical Characterization of Flagellar Motor Functions
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细菌周等离子体力转换器的起源和演变
Daniel P Williams-Jones1, Melissa N Webby1, James E Bray2
1Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK.
Molecular biology and evolution
|June 21, 2025
概括
研究人员使用结构预测追踪了细菌外膜蛋白 TolA 和 TonB 的进化起源. 他们发现TolA可能是从TonB进化而来的,并确定了新的力传导系统和外膜结合机制.
科学领域:
- 微生物学 微生物学
- 进化生物学 进化生物学
- 结构生物学 结构生物学
背景情况:
- 双膜细菌利用结合的内膜和外膜过程.
- TolA和TonB蛋白质将内膜能量与外膜功能 (如稳定和进口) 联系起来.
- 低序列保存阻碍了理解这些力转导蛋白质的演化.
研究的目的:
- 阐明 TolA 和 TonB 蛋白质的进化轨迹和起源.
- 用结构预测来识别和注释力转导操作子.
- 追踪这些系统在细菌中的分布和进化历史.
主要方法:
- 利用结构预测方法来分析蛋白质家族.
- 识别和注释的力转导在各种细菌种群中运行.
- 我们比较了Tol-Pal和Ton系统的分布.
主要成果:
- 发现了一种新型的外膜连接系统和一系列新的单体力传感器.
- 揭示了多种细菌中tol-pal操作子的核心组织原理.
- 发现TolA的α-螺旋域II结构异常,主要在γ-蛋白质细菌中流行.
- 建议的TolA是从TonB对应物进化出来的,并与Pal.一起出现.
- 确定的TolB可能起源于外膜蛋白质,而CpoB是一个祖先的脂蛋白.
结论:
- 托尔-帕尔系统在Gracilicutes中得到了广泛的保存,这强调了它在细菌细胞生物学中的重要性.
- 结构预测是追踪保存的蛋白质系统进化的强大工具.
- 这项研究揭示了对必要细菌外膜蛋白系统的共同进化有新的见解.
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