title: E. coli superdiffusion and chemotaxis-search strategy, precision, and motility.
abstract: Escherichia coli motion is characterized by a sequence of consecutive tumble-and-swim events. In the absence of chemical gradients, the length of individual swims is commonly believed to be distributed exponentially. However, recently there has been experimental indication that the swim-length distribution has the form of a power-law, suggesting that bacteria might perform superdiffusive Lévy-walk motion. In E. coli, the power-law behavior can be induced through stochastic fluctuations in the level of CheR, one of the key enzymes in the chemotaxis signal transmission pathway. We use a mathematical model of the chemotaxis signaling pathway to study the influence of these fluctuations on the E. coli behavior in the absence and presence of chemical gradients. We find that the population with fluctuating CheR performs Lévy-walks in the absence of chemoattractants, and therefore might have an advantage in environments where nutrients are sparse. The more efficient search strategy in sparse environments is accompanied by a generally larger motility, also in the presence of chemoattractants. The tradeoff of this strategy is a reduced precision in sensing and following gradients, as well as a slower adaptation to absolute chemoattractant levels.
authors.affiliation: Center for Modeling and Simulation in the Biosciences (BIOMS), University of Heidelberg, Heidelberg, Germany. franziska.matthaeus@iwr.uni-heidelberg.de
authors.forename: F
authors.initials: F
authors.lastname: Matthäus
authors.forename: M
authors.initials: M
authors.lastname: Jagodic
authors.forename: J
authors.initials: J
authors.lastname: Dobnikar
mesh_terms: D002465:Cell Movement / Q000502:physiology; D002633:Chemotaxis / Q000502:physiology*; D003198:Computer Simulation; D004926:Escherichia coli / Q000502:physiology*; D008954:Models, Biological
references.citation: Ecology. 2007 Aug;88(8):1962-9
references.pmid: 17824427
references.citation: Nature. 1997 Jun 26;387(6636):913-7
references.pmid: 9202124
references.citation: J Anim Ecol. 2007 Mar;76(2):222-9
references.pmid: 17302829
references.citation: Nature. 2004 Apr 1;428(6982):574-8
references.pmid: 15058306
references.citation: Nature. 2007 Oct 25;449(7165):1044-8
references.pmid: 17960243
references.citation: Nature. 1972 Oct 27;239(5374):500-4
references.pmid: 4563019
references.citation: J Mol Biol. 1984 Jul 5;176(3):349-67
references.pmid: 6748079
references.citation: FEBS Lett. 2003 Aug 28;550(1-3):135-8
references.pmid: 12935899
references.citation: J Bacteriol. 2005 Jan;187(1):45-53
references.pmid: 15601687
references.citation: Curr Biol. 2007 Jan 9;17(1):12-9
references.pmid: 17208180
references.citation: PLoS Comput Biol. 2008 Jan;4(1):e1
references.pmid: 18179279
references.citation: Nature. 2006 Jan 26;439(7075):462-5
references.pmid: 16437114
references.citation: Biophys J. 2002 Apr;82(4):1809-17
references.pmid: 11916840
references.citation: Bioinformatics. 2001 Jun;17(6):575-6
references.pmid: 11395441
references.citation: Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Jul;78(1 Pt 1):011906
references.pmid: 18763981
references.citation: Nature. 1999 Oct 28;401(6756):911-4
references.pmid: 10553906
references.citation: Science. 2000 Mar 3;287(5458):1652-5
references.pmid: 10698740
references.citation: J Mol Biol. 2003 May 30;329(2):291-309
references.pmid: 12758077
references.citation: Proc Natl Acad Sci U S A. 2008 Mar 4;105(9):3304-9
references.pmid: 18299569
references.citation: Proc Biol Sci. 2006 Jul 22;273(1595):1743-50
references.pmid: 16790406
references.citation: Nature. 2005 Nov 24;438(7067):504-7
references.pmid: 16306993
references.citation: Proc Natl Acad Sci U S A. 2008 Apr 29;105(17):6403-8
references.pmid: 18427119
references.citation: Appl Environ Microbiol. 2006 Jul;72(7):4987-94
references.pmid: 16820497
references.citation: Ecology. 2008 Apr;89(4):905-12
references.pmid: 18481513
references.citation: J Bacteriol. 2000 May;182(10):2793-801
references.pmid: 10781548
references.citation: Phys Rev Lett. 2005 May 27;94(20):208101
references.pmid: 16090291
references.citation: Phys Rev Lett. 2002 Mar 4;88(9):097901
references.pmid: 11864054
references.citation: Bioinformatics. 2005 Jun 1;21(11):2714-21
references.pmid: 15774553
references.citation: Nature. 2008 Feb 28;451(7182):1098-102
references.pmid: 18305542