Abstract:
:The chemotaxis network in Escherichia coli is remarkable for its sensitivity to small relative changes in the concentrations of multiple chemical signals. We present a model for signal integration by mixed clusters of interacting two-state chemoreceptors. Our model results compare favorably to the results obtained by Sourjik and Berg with in vivo fluorescence resonance energy transfer. Importantly, we identify two distinct regimes of behavior, depending on the relative energies of the two states of the receptors. In regime I, coupling of receptors leads to high sensitivity, while in regime II, coupling of receptors leads to high cooperativity, i.e., high Hill coefficient. For homogeneous receptors, we predict an observable transition between regime I and regime II with increasing receptor methylation or amidation.
journal_name
Proc Natl Acad Sci U S Aauthors
Keymer JE,Endres RG,Skoge M,Meir Y,Wingreen NSdoi
10.1073/pnas.0507438103keywords:
subject
Has Abstractpub_date
2006-02-07 00:00:00pages
1786-91issue
6eissn
0027-8424issn
1091-6490pii
0507438103journal_volume
103pub_type
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