TABLE 1.

Total effective attachment rates measured for wild-type, tumbly, smooth-swimming, and paralyzed E. coli to glass in the parallel-plate flow chamber

E. coli cell type	Mean total effective attachment rates ± SD (103)a at:
	0.0044 cm s−1 at:		0.044 cm s−1 at:
	I = 0.2 M	I = 0.02 M	I = 0.2 M	I = 0.02 M
Wild type	32 ± 2b	32 ± 8	4.8 ± 1b	5.6 ± 2
Paralyzed	63 ± 26b	14 ± 5∗	6.0 ± 2b	0.61 ± 0.15c∗
Smooth swimming	50 ± 8∗	33 ± 5	1.9 ± 0.6∗	-∗
Tumblyc	12 ± 5∗	-∗	0.48 ± 0.1∗	-∗

^aThe rates presented are nondimensional to illustrate the effect of fluid velocity; dimensional rates can be obtained by multiplying the slope (nondimensional rate) by uh/x. Three experiments were performed for wild-type and paralyzed bacteria for all conditions; three experiments were also performed for smooth-swimming bacteria for all conditions except 0.044 cm s⁻¹ and 0.2 M, for which only two experiments were performed because there was no interaction. Two experiments were performed for tumbly bacteria for all conditions tested. The reported error is one standard deviation of the slope. I, ionic strength. -, No attached cells were observed on the glass surface during the experiment (∼1.5 hr). ∗, Statistically different than the wild-type (for the same conditions).

^bData for wild-type and paralyzed E. coli strains in 0.2 M buffer are from McClaine and Ford (26).

^cWe report an attachment rate, but note that the number of cells that attached during experiments ranged between 8 and 15 cells per field.