细菌鞭毛马达适应性重组的动力学特征及其分子机制

Normally motor is thought to be structurely stable. However, recent studies started to show that the bacterial flagellar motor is a dynamic structure, with parts going on and off. It can adaptively remodel its structure to accomodate changes in the environment. This adaptive remodeling mechanism may be a common operating mechanism of protein molecular machines. The adaptive remodeling of bacterial flagellar motor consists of remodeling in the stators and the C-ring, but their dynamic properties and molecular mechanisms are still unclear. Here, we combine techniques from molecular biology, physical chemistry, optics, and statistical physics, and combine quantitative experiments with theoretical modeling, to systematically study the dynamic properties and molecular mechanisms of adaptive remodeling of the bacterial flagellar motor. This study will promote further understanding of the adaptive remodeling mechanisms of other protein machines that is wide-spread in biology.

通常意义上的马达是一个稳固、部件不变的结构。然而，最新的实验表明，细菌鞭毛马达的构成是动态的，它能根据外界环境的变化适应性地改变其构成。这种适应性重组机制很可能广泛存在于蛋白质分子机器中。细菌鞭毛马达的适应性重组有定子重组和C环重组这两方面，它们的动力学特征及分子机制尚不清楚。本项目将结合分子生物学、物理化学、光学、统计物理等多学科技术，将实验定量观测与理论模拟相结合，来系统研究鞭毛马达适应性重组的动力学特征及分子机制。这一研究将有助于深入认识生物体中广泛存在的其它蛋白质分子机器的适应性重组机制。

细菌鞭毛马达能根据外界环境的变化而适应性地改变其构成，其适应性重组有定子重组和转子C环重组这两方面。本项目结合分子生物学、物理化学、光学、统计物理等多学科技术，将实验定量观测与理论模拟相结合，系统研究了鞭毛马达适应性重组的动力学特征及分子机制，发现鞭毛马达定子重组动力学过程的暗态，发现马达转子单元适应性重组能提高细菌趋化适应速度。我们对鞭毛马达的其它机制也做了研究，包括第二信使分子c-di-GMP调控马达的机制，马达转向别构调控的非平衡机制，以及马达定子占空比的精确测量。在本项目执行期间，共发表通讯作者SCI论文7篇，包括Science Advances 1篇，Nature Physics 1篇，PNAS 1篇，Biophysical Journal 3篇，Phys. Rev. E 1篇。