FIG. 3.

Uptake of iron by L. lactis MG1363 (wt) and the mntH mutant either in the absence (left) or in the presence (right) of manganese. The total amount of Fe²⁺ added to the cells was 100 nmol (final concentration, 99 μM). Mn²⁺ was added at a 10-fold-higher concentration (990 μM) shortly before the addition of Fe²⁺. Fe²⁺ remaining in the supernatant was measured after 30 min. Triplicate iron uptake assays were performed.