在细菌中,MreB相关的细胞壁生物合成复合物的渐进运动
Julia Domínguez-Escobar1, Arnaud Chastanet, Alvaro H Crevenna
1Max Planck Institute of Biochemistry, Martinsried, Germany.
概括
在 Bacillus subtilis 中,MreB 蛋白质形成动态斑块,而不是螺旋丝,沿细胞壁移动. 这种运动由细胞壁合成提供动力,指导细菌的形状决定.
科学领域:
- 细菌细胞生物学 细菌细胞生物学
- 微生物的形态发生.
- 细胞骨动力学 细胞骨动力学
背景情况:
- 棒状细菌依赖于类甘氨酸细胞壁和MreB细胞骨来形成形状.
- 现有的模型提出螺旋式MreB丝导向细胞壁合成.
研究的目的:
- 想象MreB和细胞壁合成之间的动态关系在活生生的细菌.
- 挑战或改进MreB功能在细胞形状确定中的主流模型.
主要方法:
- 使用了全内部反射光显微镜 (TIRFm).
- 在指数增长期间观察到活生生的细菌细菌细胞.
主要成果:
- 组装成离散的MreB蛋白质,移动的补丁,而不是螺旋结构.
- 这些MreB补丁沿着垂直于细胞轴的外围轨道移动.
- 细胞壁合成为补丁运动提供动力,MreB限制扩散和定向运动.
结论:
- 螺旋MreB纤维的普遍模式在生长过程中不支持 Bacillus subtilis.
- MreB在动态补丁中起作用,这些补丁与类甘氨酸合成相结合,用于细胞延长.
- 这为细菌细胞维护形状的机制提供了新的视角.
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