Kumar M Siva, Philominathan P
Indian School Muscat, Muscat, Oman.
AVVM SriPushpam College, Tanjore, India.
Biophys Rev. 2010 Feb;2(1):13-20. doi: 10.1007/s12551-009-0024-5. Epub 2009 Dec 18.
Flagellar motion has been an active area of study right from the discovery of bacterial chemotaxis in 1882. During chemotaxis, E. coli moves with the help of helical flagella in an aquatic environment. Helical flagella are rotated in clockwise or counterclockwise direction using reversible flagellar motors situated at the base of each flagellum. The swimming of E. coli is characterized by a low Reynolds number that is unique and time reversible. The random motion of E. coli is influenced by the viscosity of the fluid and the Brownian motion of molecules of fluid, chemoattractants, and chemorepellants. This paper reviews the literature about the physics involved in the propulsion mechanism of E. coli. Starting from the resistive-force theory, various theories on flagellar hydrodynamics are critically reviewed. Expressions for drag force, elastic force and velocity of flagellar elements are derived. By taking the elastic nature of flagella into account, linear and nonlinear equations of motions are derived and their solutions are presented.
自1882年发现细菌趋化性以来，鞭毛运动一直是一个活跃的研究领域。在趋化过程中，大肠杆菌在水生环境中借助螺旋鞭毛移动。螺旋鞭毛通过位于每个鞭毛基部的可逆鞭毛马达沿顺时针或逆时针方向旋转。大肠杆菌的游动具有低雷诺数的特点，这是独特且时间可逆的。大肠杆菌的随机运动受流体粘度以及流体分子、化学引诱剂和化学驱避剂的布朗运动影响。本文综述了有关大肠杆菌推进机制所涉及物理原理的文献。从阻力理论出发，对各种鞭毛流体动力学理论进行了批判性综述。推导了鞭毛元件的阻力、弹力和速度表达式。考虑到鞭毛的弹性性质，推导了线性和非线性运动方程并给出了它们的解。
