... up-regulation of many genes in E. coli including ahpC, mdaB, nfnB, nfo, sodA, yggX and ygfZ.Byanalyzing minimal inhibition concentration and inhibition zones of plumbagin in various gene-disruption mutants,ygfZ ... criticalresidue in the fingerprint region of YgfZ followed byFigure 2 Different roles played by YgfZ and SodA in counteracting plumbagin. The ΔygfZ and ΔsodA strains were transformed with pQE-sodA and ... the ΔygfZ E. coli strain in the presence of plumbagin. Plasmids were separately transformed into the ΔygfZ strain and assayed for thediameters of the growth inhibition zone as in Figure 1B. Inset:...