help button home button Biophys. J.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Albert, R.
Right arrow Articles by Othmer, H. G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Albert, R.
Right arrow Articles by Othmer, H. G.
Biophysical Journal 86:2650-2659 (2004)
© 2004 The Biophysical Society

Dynamic Receptor Team Formation Can Explain the High Signal Transduction Gain in Escherichia coli

Réka Albert, Yu-wen Chiu and Hans G. Othmer

School of Mathematics, University of Minnesota, Minneapolis, Minnesota

Correspondence: Address reprint requests to Asst. Prof. Réka Albert at her current address: Pennsylvania State University, Dept. of Physics, 104 Davey Laboratory, PMB 261, University Park, PA 16802. Tel.: 814-865-6123; E-mail: ralbert{at}phys.psu.edu.

Evolution has provided many organisms with sophisticated sensory systems that enable them to respond to signals in their environment. The response frequently involves alteration in the pattern of movement, either by directed movement, a process called taxis, or by altering the speed or frequency of turning, which is called kinesis. Chemokinesis has been most thoroughly studied in the peritrichous bacterium Escherichia coli, which has four helical flagella distributed over the cell surface, and swims by rotating them. When rotated counterclockwise the flagella coalesce into a propulsive bundle, producing a relatively straight "run," and when rotated clockwise they fly apart, resulting in a "tumble" which reorients the cell with little translocation. A stochastic process generates the runs and tumbles, and in a chemoeffector gradient, runs that carry the cell in a favorable direction are extended. The cell senses spatial gradients as temporal changes in receptor occupancy and changes the probability of counterclockwise rotation (the bias) on a fast timescale, but adaptation returns the bias to baseline on a slow timescale, enabling the cell to detect and respond to further concentration changes. The overall structure of the signal transduction pathways is well characterized in E. coli, but important details are still not understood. Only recently has a source of gain in the signal transduction network been identified experimentally, and here we present a mathematical model based on dynamic assembly of receptor teams that can explain this observation.




This article has been cited by other articles:


Home page
 Biophys. JHome page
M. L. Skoge, R. G. Endres, and N. S. Wingreen
Receptor-Receptor Coupling in Bacterial Chemotaxis: Evidence for Strongly Coupled Clusters
Biophys. J., June 15, 2006; 90(12): 4317 - 4326.
[Abstract] [Full Text] [PDF]

Home page
 J. Bacteriol.Home page
L. Liberman, H. C. Berg, and V. Sourjik
Effect of Chemoreceptor Modification on Assembly and Activity of the Receptor-Kinase Complex in Escherichia coli
J. Bacteriol., October 1, 2004; 186(19): 6643 - 6646.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2004 by the Biophysical Society.