Fluctuation analysis of mechanochemical coupling depending on the type of bio-molecular motor
Abstract
Mechanochemical coupling was studied for two different types of myosin motors in cells: myosin V, which carries cargo over long distances by as a single molecule; and myosin II, which generates a contracting force in cooperation with other myosin II molecules. Both mean and variance of myosin V velocity at various [ATP] obeyed Michaelis-Menten mechanics, consistent with tight mechanochemical coupling. Myosin II, working in an ensemble, however, was explained by a loose coupling mechanism, generating variable step sizes depending on the ATP concentration and realizing a much larger step (200 nm) per ATP hydrolysis than myosin V through its cooperative nature at zero load. These different mechanics are ideal for the respective myosin's physiological functions.
Keywords
Cite
@article{arxiv.0801.1392,
title = {Fluctuation analysis of mechanochemical coupling depending on the type of bio-molecular motor},
author = {Masatoshi Nishikawa and Hiroaki Takagi and Atsuko H. Iwane and Toshio Yanagida},
journal= {arXiv preprint arXiv:0801.1392},
year = {2009}
}