Movements of Mycoplasma mobile Gliding Machinery Detected by High-Speed Atomic Force Microscopy.
Movements of Mycoplasma mobile Gliding Machinery Detected by High-Speed Atomic Force Microscopy.
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DOI：
10.1128/mbio.00040-21
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发表时间：
2021-06-29
期刊：
影响因子：
6.4
通讯作者：
Miyata M
中科院分区：
文献类型：
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作者：
Kobayashi K;Kodera N;Kasai T;Tahara YO;Toyonaga T;Mizutani M;Fujiwara I;Ando T;Miyata M
移动支原体是一种寄生细菌，通过特殊的机制在动物细胞和玻璃等固体表面上滑动。这个过程是由 ATP 水解在内部结构上产生的力驱动的。然而，活细胞内部结构的空间和时间行为尚不清楚。在这项研究中，我们通过使用高速原子力显微镜（HS-AFM）扫描固定在玻璃基板上的细胞来检测内部结构的运动。通过扫描细胞表面，我们成功地观察到了高度为 2 nm 的颗粒，这些颗粒主要沿细胞轴排列，间距为 31.5 nm，这与之前报道的基于电子显微镜的特征一致。然后通过 HS-AFM 分析单个粒子的运动。在叠氮化钠存在的情况下，颗粒运动的平均速度降低，表明运动与 ATP 水解有关。叠氮化钠对反应的部分抑制使我们能够详细分析颗粒行为，结果表明颗粒相对于滑动方向向右移动 9nm，并在 330ms 内移动 2nm 进入细胞内部，然后根据 ATP 水解返回到其原始位置。
Mycoplasma mobile, a parasitic bacterium, glides on solid surfaces, such as animal cells and glass, by a special mechanism. This process is driven by the force generated through ATP hydrolysis on an internal structure. However, the spatial and temporal behaviors of the internal structures in living cells are unclear. In this study, we detected the movements of the internal structure by scanning cells immobilized on a glass substrate using high-speed atomic force microscopy (HS-AFM). By scanning the surface of a cell, we succeeded in visualizing particles, 2 nm in height and aligned mostly along the cell axis with a pitch of 31.5 nm, consistent with previously reported features based on electron microscopy. Movements of individual particles were then analyzed by HS-AFM. In the presence of sodium azide, the average speed of particle movements was reduced, suggesting that movement is linked to ATP hydrolysis. Partial inhibition of the reaction by sodium azide enabled us to analyze particle behavior in detail, showing that the particles move 9 nm right, relative to the gliding direction, and 2 nm into the cell interior in 330 ms and then return to their original position, based on ATP hydrolysis.