... 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 ... plumbaginwere then determined. The MIC of the parental strainwas expectedly much higher than those of the ΔygfZand ΔsodA mutants (Table 3). To ensure that the plum-bagin-sensitivity of the ΔygfZ ... activities of different YgfZ constructs to support the growth of the ΔygfZ E. coli strain in the presence of plumbagin. Plasmids were separately transformed into the ΔygfZ strain and assayed for the diameters...