TABLE 2.

Down-regulation of rob in response to PQ: exposure time^a

Time (min)	Mean rob/gapA ratio ± SEMb	Variationc (fold)
0	1.63 ± 0.19	1.0
<1	0.77 ± 0.07	2.1*
5	0.08 ± 0.01	20.4*
10	0.15 ± 0.02	10.9*

^aThat is, the time course of the response of wild-type bacteria at 100 μM PQ.

^bSee Table 1, footnote b.

^cSee Table 2, footnote c.