Unidirectional motility of Escherichia coli in restrictive capillaries

Abstract

In a 6-μm capillary filled with buffer and in the absence of any chemotactic stimuli, Escherichia coli K-12 cells swim persistently in only one direction. This behavior or E. coli can be simply explained by means of the length and relative rigidity of their flagella. Single-cell motility parameters-swimming speed, turn angle, and run length time-were measured. Compared with the motility parameters measured in bulk phase, turn angle was influenced because of the effect of the geometrical restriction.