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Directional persistence and the optimality of run-and-tumble chemotaxis

Dan V. Nicolau, Judith P. Armitage, Philip K. Maini
2009 Computational biology and chemistry  
E. coli does chemotaxis by performing a biased random walk composed of alternating periods of swimming (runs) and reorientations (tumbles).  ...  The agreement between model and experiments suggests that directional persistence may serve some function, a hypothesis supported by the results of an earlier model.  ...  In this paper we investigate the effect of directional memory on the optimality of run-and-tumble chemotaxis by using this measure.  ... 
doi:10.1016/j.compbiolchem.2009.06.003 pmid:19616478 fatcat:bqktkyhd5vbm3nbojg3g3r6rt4

The role of tumbling frequency and persistence in optimal run-and-tumble chemotaxis [article]

Julius B. Kirkegaard, Raymond E. Goldstein
2017 arXiv   pre-print
One of simplest examples of navigation found in nature is run-and-tumble chemotaxis.  ...  Here we study persistent run-and-tumble dynamics, focusing first on the optimisation of the linearised chemotactic response within the two-dimensional parameter space of tumble frequency and angular persistence  ...  The epitome of chemotaxis is perhaps the run-and-tumble of certain peritrichously flagellated bacteria such as E. coli [7] .  ... 
arXiv:1709.04375v1 fatcat:2tn2oj7tmzh3pdfagstvls34zq

Run and tumble chemotaxis in a shear flow: the effect of temporal comparisons and other complications [article]

J. T. Locsei, T. J. Pedley
2008 arXiv   pre-print
makes temporal comparisons of chemoattractant concentration, (ii) the tumbles exhibit persistence of direction, meaning that the swimming directions before and after a tumble are correlated, (iii) the  ...  of maximising drift velocity, persistence of direction is advantageous in a quiescent fluid but disadvantageous in a shear flow, and (c) a more elongated body shape is advantageous in performing chemotaxis  ...  The authors are grateful for enlightening discussions with John Rallison, Ray Goldstein, Howard Berg, Henry Fu, Roman Stocker, Marcos, and Rachel Bearon.  ... 
arXiv:0804.2352v1 fatcat:rawywydfibeepaftd5y54ep42e

Persistence of direction increases the drift velocity of run and tumble chemotaxis

J. T. Locsei
2007 Journal of Mathematical Biology  
concentration, (ii) rather than being entirely random, tumbles exhibit persistence of direction, meaning that the new direction after a tumble is more likely to be in the forward hemisphere, and (iii)  ...  Previous models of run and tumble chemotaxis neglect one or more features of the motion, namely (i) a cell cannot directly detect a chemoattractant gradient but rather makes temporal comparisons of chemoattractant  ...  Acknowledgements I would like to thank Professor Tim Pedley for his guidance and encouragement, Dr Kalvis Jansons for his advice on notation, and Professor Howard Berg for fruitful conversations.  ... 
doi:10.1007/s00285-007-0080-z pmid:17354016 fatcat:2266meye65dvhcdngkudul4w4y

Chemotaxis as a model for sensory systems

D.E. Koshland
1974 FEBS Letters  
After analyzing 2400 run lengths of Salmonella in such gradients a persistence time between 1 and 10 set was obtained [28] .  ...  Persistence numbers from the beginning of the path shown are 2, 3, 2, etc. in the +z direction and 1,4, 1, etc. in the -z direction. North-Holland Publishing Company -Amsterdam  ... 
doi:10.1016/0014-5793(74)80683-6 fatcat:a6te5poumffhffbxrrohbaxcq4

Optimal chemotactic responses in stochastic environments

Martin Godány, Bhavin S. Khatri, Richard A. Goldstein, Christopher V. Rao
2017 PLoS ONE  
By tumbling persistently when the current concentration is higher than the average, bacteria maintain their position in regions of high attractant concentration.  ...  Most of our understanding of bacterial chemotaxis comes from studies of Escherichia coli.  ...  ACKNOWLEDGMENTS We would like to thank Orkun Soyer and Christopher Monit for helpful discussions and funding from the Medical Research Council, U.K (funding reference U117573805).  ... 
doi:10.1371/journal.pone.0179111 pmid:28644830 pmcid:PMC5482444 fatcat:42bmb6j5lzenffhtaprb5m5yqu

Optimal Chemotactic Responses in Stochastic Environments [article]

Martin Godány, Bhavin S. Khatri, Richard A. Goldstein
2015 arXiv   pre-print
By tumbling persistently when the current concentration is higher than the average, bacteria maintain their position in regions of high attractant concentration.  ...  Most of our understanding of bacterial chemotaxis comes from studies of Escherichia coli.  ...  ACKNOWLEDGMENTS We would like to thank Orkun Soyer and Christopher Monit for helpful discussions and funding from the Medical Research Council, U.K (funding reference U117573805).  ... 
arXiv:1503.07846v1 fatcat:zlddqaggyzcfhbdxddg4o2kxsq

Optimal chemotaxis in animal cell intermittent migration [article]

Pawel Romanczuk, Guillaume Salbreux
2015 arXiv   pre-print
We obtain analytical results for the catching time and for the spatial dispersion in the limits of small and large ratios of run time to tumble time, and scaling laws for the optimal run times.  ...  Here we discuss optimal search strategies for a chaser that moves by switching between two phases of motion ("run" and "tumble"), reorienting itself towards the target during tumble phases, and performing  ...  Acknowledgements We thank Ewa Paluch for bringing cellular run and tumble motion to our attention and for stimulating discussions, and Vasily Zaburdaev for helpful comments on the manuscript.  ... 
arXiv:1503.05054v1 fatcat:i2fuzbvohbennh4a6ehb6h2xea

Limits of Feedback Control in Bacterial Chemotaxis

Yann S. Dufour, Xiongfei Fu, Luis Hernandez-Nunez, Thierry Emonet, Jason M. Haugh
2014 PLoS Computational Biology  
This optimal regime is outside the dynamic range of the motor response, but maximizes the contrast between run duration up and down gradients.  ...  In bacterial chemotaxis, robust performance is often attributed to the zero integral feedback control of the sensor, which guarantees that activity returns to resting state when the input remains constant  ...  Therefore, directional persistence will shift the optimal CheY-P concentration to higher concentrations and improve the drift velocity of frequently tumbling cells [44] .  ... 
doi:10.1371/journal.pcbi.1003694 pmid:24967937 pmcid:PMC4072517 fatcat:3i2lpodjdjc6fezk2yjoey5bse

Tumble Suppression Is a Conserved Feature of Swarming Motility

Jonathan D. Partridge, Nguyen T. Q. Nhu, Yann S. Dufour, Rasika M. Harshey, Caroline S. Harwood
2020 mBio  
The demonstrated property of E. coli to reduce its tumble bias and hence increase its run duration during swarming is expected to maintain and promote side-by-side alignment and cohesion within the bacterial  ...  We recently demonstrated another swarming adaptation in Escherichia coli, wherein the chemotaxis pathway is remodeled to decrease tumble bias (increase run durations), with running speeds increased as  ...  We recently reported that E. coli cells taken from a swarm exhibit more highly extended runs and higher speeds than planktonic cells and that this low tumble bias is the optimal bias for maximizing swarm  ... 
doi:10.1128/mbio.01189-20 pmid:32546625 fatcat:g36lpmrmqfedxf5k6w2oiqsd24

Flagellar number governs bacterial spreading and transport efficiency

Javad Najafi, Mohammad Reza Shaebani, Thomas John, Florian Altegoer, Gert Bange, Christian Wagner
2018 Science Advances  
We find that decreasing the number of flagella Nf reduces the average turning angle between two successive run phases and enhances the run time and the directional persistence of the run phase.  ...  The results of numerical simulations based on our two-state model suggest that the efficiency of searching and exploring the environment is optimized at intermediate values of Nf.  ...  (E) MFPT, scaled by MFPT at p = 0 versus the directional persistency p of the run phase. Inset: Optimal persistency p opt versus the effective system size L/'.  ... 
doi:10.1126/sciadv.aar6425 fatcat:3poi4uwobbhrvlkbxso42hruue

Propulsion and Chemotaxis in Bacteria-Driven Microswimmers

Jiang Zhuang, Byung-Wook Park, Metin Sitti
2017 Advanced Science  
relation characterized by Stoke's law, we can conclude that the propulsive force of the running states is approximately constant, while the propulsive force is relatively negligible during the tumble  ...  Furthermore, the dependencies of the motility and chemotaxis of the microswimmers on certain system parameters, such as the chemoattractant concentration gradient, swimmer body size, and number of attached  ...  reorientation angle is around 80, showing a slight directional persistence between two consecutive runs  ... 
doi:10.1002/advs.201700109 pmid:28932674 pmcid:PMC5604384 fatcat:cpulgt5qnjh3rlt3jqy2kc3f3e

Chemotaxis in external fields: Simulations for active magnetic biological matter

Agnese Codutti, Klaas Bente, Damien Faivre, Stefan Klumpp, Oleg A Igoshin
2019 PLoS Computational Biology  
Here we introduce a variant of these models with several internal states of the swimmer to describe stochastic strategies for directional swimming such as run and tumble or run and reverse that are used  ...  We show how this modified model can be applied to various scenarios: First, the run and tumble motion of E. coli is used to establish a paradigm for chemotaxis and investigate how it is affected by external  ...  The paradigm for such directional guidance is the chemotaxis of bacteria such as Escherichia coli, which alternate between straight runs and abrupt changes of direction called tumbles.  ... 
doi:10.1371/journal.pcbi.1007548 pmid:31856155 pmcid:PMC6941824 fatcat:iwuidcip65hdpnxyerinegccgi

Cellular memory enhances bacterial chemotactic navigation in rugged environments

Adam Gosztolai, Mauricio Barahona
2020 Communications Physics  
Here we study theoretically the role of cellular memory in Escherichia coli chemotaxis.  ...  Maximal advantage is achieved when the memory is comparable to the time scale of fluctuations as perceived during swimming.  ...  We thank Eduardo Sontag, on one hand, and Nils Becker and Pieter Rein ten Wolde, on the other, for providing us with their agent-based codes, which helped the development and validation of our models.  ... 
doi:10.1038/s42005-020-0312-8 fatcat:ctgrqoljdngallaoepxs3rfsxi

Beyond local gradient-sensing: memory effects in bacterial chemotactic navigation [article]

Adam Gosztolai, Mauricio Barahona
2019 biorxiv/medrxiv   pre-print
Here we study the role of cellular memory in Escherichia coli chemotaxis.  ...  Our model explains the improved velocity, and recovers standard Keller-Segel gradient-sensing results in the limits of no cellular memory, no ruggedness of the landscape, and when memory and fluctuation  ...  We thank Eduardo Sontag, on one hand, and Nils Becker and Pieter Rein ten Wolde, on the other, for providing us with their agent-based codes, which helped the development and validation of our models.  ... 
doi:10.1101/733345 fatcat:fkmbpryadvebthl4yfz565b7jy
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