Table 1.

Bacterial strains used

Species and strain	Description	Source and/or reference(s)a
E. coli BW25113	wt	3
E. coli BW25113 cyaA::kan	Lacks adenylate cyclase gene	3, 48
E. coli BW25113 cpd::kan	Lacks cAMP-phosphodiesterase gene	3, 22
E. coli BW25113 crp::kan	Lacks cAMP receptor protein	3, 14
E. coli BW25113 sdiA::kan	Lacks luxR homologue (receptor for AHLs and indole)	3, 30, 43
E. coli BW25113 tnaA::kan	Lacks tryptophanase	3, 23
E. coli MG1655	wt	D. A. Siegele (6)
E. coli MG1655 purH	Lacks IMP cyclohydrolase (purine synthesis)	F. R. Blattner (25)
E. coli MG1655 purD	Lacks phosphoribosyltransferase (purine synthesis)	F. R. Blattner (25)
E. coli ZK126	wt	D. A. Siegele (1)
Pseudomonas aeruginosa PAO1	wt	V. Deretic (45)
P. aeruginosa PDO100 ΔrhlI::Tn501	Lacks AHL synthase for C4-HSL	E. P. Greenberg (50)
P. aeruginosa PAO-MW1 ΔrhlI ΔlasI	Lacks AHL synthases for C4-HSL and 3-o-C12-HSL	E. P. Greenberg (50)

^aE. coli BW25113 strains were obtained from the Genome Analysis Project in Japan.