Fig 8.

Effects of null mutations of DNA- associated proteins (A) and a Dps null mutant strain (B) on bactericidal activity. (A) Treatment with 13.75 mM EIP-K plus 3 mM H₂O₂ and untreated (number of cells at time zero). The values are means and SEM for two experiments, each run in triplicate. NT3 is the parental strain for the Δhup, ΔhimA, Δhns, and ΔmukB mutants, and ZK126 is the parental strain for the Δdps mutant. Two-way ANOVA shows a significant treatment effect (F_[1,21] = 68.96; P = 0.0000001), a nonsignificant mutant effect (F_[5,21] = 1.27; P = 0.314), and a nonsignificant treatment-mutant interaction effect (F_[6,21] = 1.269; P = 0.313. The lack of asterisks indicates that the mutant strains showed effects similar to those of the wild type under EIP-K-plus-H₂O₂ treatment. (B) Various concentrations of H₂O₂, alone or with 13.75 mM EIP-K, and 13.75 mM EIP-K alone were tested on a Dps null mutant strain and compared with the wild-type (WT) strain or the Dps null mutant. The values are means and SEM for one experiment run in duplicate.