title: Universal response-adaptation relation in bacterial chemotaxis.
abstract: The bacterial strategy of chemotaxis relies on temporal comparisons of chemical concentrations, where the probability of maintaining the current direction of swimming is modulated by changes in stimulation experienced during the recent past. A short-term memory required for such comparisons is provided by the adaptation system, which operates through the activity-dependent methylation of chemotaxis receptors. Previous theoretical studies have suggested that efficient navigation in gradients requires a well-defined adaptation rate, because the memory time scale needs to match the duration of straight runs made by bacteria. Here we demonstrate that the chemotaxis pathway of Escherichia coli does indeed exhibit a universal relation between the response magnitude and adaptation time which does not depend on the type of chemical ligand. Our results suggest that this alignment of adaptation rates for different ligands is achieved through cooperative interactions among chemoreceptors rather than through fine-tuning of methylation rates for individual receptors. This observation illustrates a yet-unrecognized function of receptor clustering in bacterial chemotaxis.
authors.affiliation: Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, Heidelberg, Germany.
authors.forename: Anna K
authors.initials: AK
authors.lastname: Krembel
authors.affiliation: Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, Heidelberg, Germany.
authors.forename: Silke
authors.initials: S
authors.lastname: Neumann
authors.affiliation: Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, Heidelberg, Germany Max Planck Institute for Terrestrial Microbiology and LOEWE Research Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany victor.sourjik@synmikro.mpi-marburg.mpg.de.
authors.forename: Victor
authors.initials: V
authors.lastname: Sourjik
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D001426:Bacterial Proteins / Q000378:metabolism; D002633:Chemotaxis / Q000502:physiology*; D004926:Escherichia coli / Q000378:metabolism* / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins