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Title: Emergence of Escherichia coli critically buckled motile helices under stress

Bacteria under external stress can reveal unexpected emergent phenotypes. We show that the intensely studied bacteriumEscherichia colican transform into long, highly motile helical filaments poized at a torsional buckling criticality when exposed to minimum inhibitory concentrations of several antibiotics. While the highly motile helices are physically either right- or left-handed, the motile helices always rotate with a right-handed angular velocityω, which points in the same direction as the translational velocityvTof the helix. Furthermore, these helical cells do not swim by a “run and tumble” but rather synchronously flip their spinωand thus translational velocity—backing up rather than tumbling. By increasing the translational persistence length, these dynamics give rise to an effective diffusion coefficient up to 20 times that of a normalE. colicell. Finally, we propose an evolutionary mechanism for this phenotype’s emergence whereby the increased effective diffusivity provides a fitness advantage in allowing filamentous cells to more readily escape regions of high external stress.

 
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Award ID(s):
1734030
NSF-PAR ID:
10080539
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Proceedings of the National Academy of Sciences
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
115
Issue:
51
ISSN:
0027-8424
Page Range / eLocation ID:
p. 12979-12984
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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