Rectified Brownian motion and kinesin motion along microtubules.
The mechanism of rectified Brownian movement is used to analyze measured data for kinesin motion along microtubules. A key component of the mechanism is the diffusive movement of the microtubule binding heads of kinesin during the adenosine triphosphate (ATP) cycle. The first-passage time distribution for this step is analyzed in detail and is shown to be responsible for observed load-velocity profiles. The ATPase activity of the kinesin heads is that of a nucleotide switch and not that of a direct chemomechanical energy converter. Experimental data acquisition, rate constants, and alternative explanations are discussed. The mechanism described in this paper is fundamental to the nanobiology of intracellular processes.
Fox
R F
RF
School of Physics and Center for Nonlinear Science, Georgia Institute of Technology, Atlanta, Georgia 30080, USA.
Choi
M H
MH
D000251:Adenosine Triphosphatases / Q000737:chemistry; D000255:Adenosine Triphosphate / Q000737:chemistry; D000818:Animals; D001665:Binding Sites; D001703:Biophysics / Q000379:methods*; D006868:Hydrolysis; D016547:Kinesins / Q000737:chemistry*; D008870:Microtubules / Q000378:metabolism*; D008954:Models, Biological; D008956:Models, Chemical; D015233:Models, Statistical; D017433:Protein Structure, Secondary; D013997:Time Factors
D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D016547:Kinesins