title: Noise underlies switching behavior of the bacterial flagellum.
abstract: We report the switching behavior of the full bacterial flagellum system that includes the filament and the motor in wild-type Escherichia coli cells. In sorting the motor behavior by the clockwise bias, we find that the distributions of the clockwise (CW) and counterclockwise (CCW) intervals are either exponential or nonexponential with long tails. At low bias, CW intervals are exponentially distributed and CCW intervals exhibit long tails. At intermediate CW bias (0.5) both CW and CCW intervals are mainly exponentially distributed. A simple model suggests that these two distinct switching behaviors are governed by the presence of signaling noise within the chemotaxis network. Low noise yields exponentially distributed intervals, whereas large noise yields nonexponential behavior with long tails. These drastically different motor statistics may play a role in optimizing bacterial behavior for a wide range of environmental conditions.
authors.affiliation: The James Franck Institute, University of Chicago, Chicago, Illinois, USA.
authors.forename: Heungwon
authors.initials: H
authors.lastname: Park
authors.forename: Panos
authors.initials: P
authors.lastname: Oikonomou
authors.forename: Calin C
authors.initials: CC
authors.lastname: Guet
authors.forename: Philippe
authors.initials: P
authors.lastname: Cluzel
mesh_terms: D004926:Escherichia coli / Q000378:metabolism*; D005407:Flagella / Q000378:metabolism*; D008954:Models, Biological; D020409:Molecular Motor Proteins / Q000378:metabolism; D009716:Numerical Analysis, Computer-Assisted; D013816:Thermodynamics
chemical_list: D020409:Molecular Motor Proteins
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