TABLE 2.

Response of acetate metabolism mutants in a gutted background to acetate

Gutted strain	Growth on acetatea	No. of cells analyzed	% Cells responding by CWb	% Cells responding by stoppingc	Response delay time (s)d
EW128 (wte)	−	36	92	0	50 ± 35
	+	32	91	9	93 ± 36
EW129 (Δacs)	−	67	67	24	138 ± 65
	+	34	65	24	106 ± 29
EW130 [Δ(ack pta)]	−	34	27	44	178 ± 86
	+	21	43	6	119 ± 32
	+f	46	70	17	67 ± 31
EW131 [Δ(acs ack pta)]	−	36	0	0	0
	+	29	0	0	0

^aGrowth on TB containing 5 mM acetate. 

^bCells were considered to be CW responders if their CCW bias decreased by at least 50% in response to acetate addition. 

^cOnly cells which came to a complete stop and did not resume the rotation until the end of the observation period (10 min after acetate addition) were considered to have responded by stopping. 

^dMean ± standard deviation. The response delay time was measured from the time that acetate entered the cell (measured in a separate experiment, with nontethered dead cells as markers) and the first response. 

^eWild type with respect to acetate metabolism. 

^fIn this experiment, the cells were grown to an OD₅₉₀ of 0.85 instead of 0.4.