Langevin computer simulations of bacterial protein filaments and the force-generating mechanism during cell division.-猫眼课题宝

朗之万对细菌蛋白丝和细胞分裂过程中力产生机制的计算机模拟。

DOI：

10.1103/physreve.77.011902

发表时间：

2008

期刊：

Physical review. E, Statistical, nonlinear, and soft matter physics

影响因子：

通讯作者：

中科院分区：

文献类型：

作者：

I. Hörger;Enrique Velasco;Jesús Mingorance;Germán Rivas;P. Tarazona;M. Vélez

FtsZ是一种细菌蛋白，在细胞分裂过程中形成细丝，在中细胞收缩过程中发挥重要作用。用原子力显微镜对不同长度的单丝的形状进行了模拟，将蛋白质单体看作链上的珠子，并用几个参数来表示它们之间的有效相互作用。估算了纤维的弯曲硬度和持久长度。后者的值与细丝长度相当，这意味着这些生物聚合物介于完全由单体之间的角度控制的完全刚性的线性聚集体和形状遵循随机行走模型的高度柔性的聚合物之间。在建模中也估计了相邻细丝之间的横向相互作用，发现它们在决定较长聚合物中发现的卷曲结构的最终形状和动力学方面起着至关重要的作用。估算的参数被用来模拟聚合物在圆柱表面上的行为。这一分析指出了螺旋结构的形成，这表明了一种通过在中间细胞分裂点发展FtsZ螺旋来产生和放大力量的机制。

FtsZ is a bacterial protein that forms filaments that play an essential role in midcell constriction during the process of cell division. The shape of individual filaments of different lengths imaged with atomic force microscopy was modeled considering the protein monomers as beads in a chain and a few parameters to represent their effective interactions. The flexural rigidity and persistence length of the filaments were estimated. This latter value was comparable to the filament length, implying that these biological polymers are halfway between the perfectly stiff linear aggregate whose shapes are fully controlled by the angle between the monomers and highly flexible polymers whose shapes follow a random walk model. The lateral interactions between adjacent filaments, also estimated in the modeling, were found to play an essential role in determining the final shape and kinetics of the coiled structures found in longer polymers. The estimated parameters were used to model the behavior of the polymers also on a cylindrical surface. This analysis points to the formation of helical structures that suggest a mechanism for force generation and amplification through the development of FtsZ spirals at the midcell division point.

A point mutation converts Escherichia coli FtsZ septation GTPase to an ATPase.