TABLE 3.

Promoter activities of xopA, xopD, and hpaF in X. campestris pv. vesicatoria strains 85-10 and 85*^a

Reporter construct (gene)	Activity (GUS units) ± SDb in strain:		Fold induction (compared to 85-10)
	85-10	85*c
pICxopA (xopA)	1.2 ± 0.2	24 ± 3	20
pICxopD (xopD)	0.24 ± 0.06	1.9 ± 0.4	8
pXV4::462 (hpaF)	0.06 ± 0.02	2.4 ± 0.5	40

^aBacteria were grown in NYG medium.

^bOne unit corresponds to 1 nmol of 4-methylumbelliferone released per min per bacterium.

^cCarries the hrpG* mutation, which leads to constitutive hrp gene expression (45).