FIG. 4.

Functional complementation of the serovar Typhimurium mntH sitABCD (mutant MS) phenotype in vitro by overexpression of the full-length mntH gene. (A and B) Divalent metal ion uptake (see Fig. 1C and D). (C) Sensitivity to DP as measured by the OD₆₀₀ reached after 6 h of subculture at 37°C and 220 rpm in LB medium containing 200 μM DP. (D) Sensitivity to H₂O₂ measured by a disk assay, as described in the text. (E) Intracellular survival and replication in macrophage-like cells in the presence of 65 μM DP, as determined by CFU plating (see Fig. 3C). The means ± standard errors of the means for two (A and B), at least five (C), at least six (D), or three (E) independent experiments are shown. For an explanation of the Salmonella strains see the legend to Fig. 1. pSKmntH, pBluescript plasmid with mntH gene; pSKmntHΔ, plasmid with a nonfunctional, truncated mntH ORF; OD1, optical density unit; φ, diameter.