Figure 2

The effect of the polyamines PUT and SPD in the transcription of the atoSC two component system genes.(a) The E. coli K12 strain BW25113 (atoSC⁺) and (b) E. coli K12 strain BW28878(ΔatoSC), were transformed with recombinant plasmids, pCPG5(atoA-lacZ) and pCPG6(atoC-lacZ), carrying the various promoters of the atoSC two component system. Polyamine-mediated induction was measured by assaying β-galactosidase expression in the presence of increasing concentrations of polyamines (0, 0.3, 0.5, 1 and 2.5 mM). The results are presented from three independent experiments, while in each experiment two clones from each transformant were tested.