TABLE 2.

Characterization of genes which affect ς^W and ς^X activity

Straina	Gene	Mini-Tn10 insertion siteb	Presumed function and/or featuresc	Downstream gene(s) possibly affected by insertiond	LB plate phenotypee
HB7070	NAf	NA	NA	NA	−/+
HB0011	rsiW	NA	Anti-ςW	NA	++
W1, W2, and W3	yvbA	244	Regulator of export	yvaZ	+++
W4	yqgE	240	Multidrug efflux	pbpA	−/+g
W5	yheH	1640	Multidrug efflux		+
W6	yhdP	260	Metal ion efflux		+
W7	yueF	931	Unknown; transport?	yueG	+
W8	oppA	391	Oligopeptide uptake	oppBCDF	++
W9	yulE	1058	Rhamnose isomerase		+
W10	pksR	6772	Difficidin synthesis		+
W11	ysdB	−43	Unknown; ςW- and possibly ςB-regulated membrane protein		+
W12	yqfD	71	Unknown; possibly ςW regulated	phoH	+
W13	yodE	240	Aromatic ring cleavage	yodD	+
W14	yshB	47	Unknown	yshCDE	++
W15	yshD	1862	DNA mismatch repair	yshE	+
W16	yopH	331	Unknown	yopIJKL	+
HB7022	NA	NA	NA	NA	−
HB7024	rsiX	NA	Anti-ςX	NA	++
X1	yitG	631	Multidrug efflux	yitFE	+
X2	yjdE	60	Mannose-6-phosphate isomerase	yjdF	+
X3	srfAB	10064	Surfactin synthesis	srfAC, srfAD	+
X4	yogA	933	Polyketide synthesis		−/+
X5	yngK	1517	Unknown		−/+
X6	ytxJ	227	Unknown		−/+
X7	ywpH	−74	DNA replication	glcR, ywpJ	+

^aMini-Tn10 mutants up-regulated in ς^W and ς^X activity begin with W and X, respectively. 

^bRelative to the first nucleotide of the gene. 

^cThe majority of predicted functions are based on those of homologous proteins (see Table 3). 

^dIn most cases, operon structures have not been characterized, but inspection of the genome sequence indicates that expression of these downstream genes would also likely be affected by the transposon insertion. We have also not ruled out possible effects of the transposon insertion on expression of upstream genes. 

^eExpression of the P_W and P_X promoters in each strain was measured by growth on 15-ml LB plates containing 40 μg of X-Gal per ml. Colony color was observed following overnight growth at 37°C and is indicated as follows: +++ (strong blue) > ++ (blue) > + (light blue) > −/+ (very light blue) > − (white). The parent (HB7070) and rsiW mutant (HB0011) strains containing the P_W-cat-lacZ fusion are included. The parent (HB7022) and rsiX mutant (HB7024) strains containing the P_X-cat-lacZ fusion are also included. 

^fNA, not applicable. 

^gAfter 2 days of growth, the yqgE mutant had significantly greater ς^W activity than did the parent strain HB7070.