Hidden stochastic nature of a single bacterial motor.
The rotary flagellar motor of Escherichia coli bacterium switches stochastically between the clockwise (CW) and counterclockwise (CCW) direction. We found that the CW and CCW intervals could be described by a gamma distribution, suggesting the existence of hidden Markov steps preceding each motor switch. Power spectra of time series of switching events exhibited a peaking frequency instead of the Lorentzian profile expected from standard kinetic two-state models. Our analysis indicates that the number of hidden steps may be a key dynamical parameter underlying the switching process in a single bacterial motor as well as in large cooperative molecular systems.
The Institute for Biophysical Dynamics, The James Franck Institute, The University of Chicago, 56540 South Ellis Avenue, Chicago, Illinois 60637, USA.
Ekaterina A
EA
Korobkova
Thierry
T
Emonet
Heungwon
H
Park
Philippe
P
Cluzel
D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology; D018988:Bacterial Translocation; D004926:Escherichia coli / Q000502:physiology*; D005407:Flagella / Q000502:physiology*; D008390:Markov Chains; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology; D000072236:Methyl-Accepting Chemotaxis Proteins; D008954:Models, Biological; D020409:Molecular Motor Proteins / Q000502:physiology*; D009154:Mutation
D001426:Bacterial Proteins; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins; D020409:Molecular Motor Proteins