Single Molecule Measurements of Molecular Motors

Abstract

Abstract Single molecule detection was developed to measure the unique operation of molecular motors. The function of molecular motors has been ascribed to the movement of a single motor molecule along a partner protein track. Manipulating single protein tracks and single motors and imaging single molecules has allowed the behaviour of such unitary machines to be measured. The mechanical responses to the energy input from the hydrolysis of ATP molecules have been determined and the underlying mechanism explored. The results indicate that the movement of molecular motors is driven by thermal motion rather than structural changes occurring in the motor molecules. Thermal Brownian motion must be biased in one direction. In this article, we summarize the methods and results of single molecule measurements of molecular motors. Originally published in: Molecular Motors. Edited by Manfred Schliwa. Copyright © 2003 Wiley‐VCH Verlag GmbH & Co. KGaA Weinheim. Print ISBN: 3‐527‐30594‐0 The sections in this article are Introduction Manipulation of Actin Filaments Nanometry of Actin Filaments Movement of Actin Filaments Caused by Single Myosin Molecules Visualization of Single Molecules Visualization of ATP Turnover and Mechano‐chemical Coupling Visualization of the Movement of Single Kinesin Motors Visualization of the Processive Movement of Single Myosin Motors Manipulation of Single Myosin Molecules with a Scanning Probe and Nanometry Biased Brownian Movement Conclusions