Functional consequences of LSPP15 overexpression. (A) 55FeCl3 uptake assay in wild-type M. avium subsp. paratuberculosis and MAP::MAP3775-2c. *, P < 0.05; ***, P < 0.001. (B) ICP-MS quantification of intracellular metal contents (Fe:Mg) of wild-type M. avium subsp. paratuberculosis and MAP::MAP3775-2c grown in 7H9 supplemented with 0%, 0.1%, or 1.0% FAC after 48 h. Data are presented as means ± standard deviations of the results of two individual experiments, each performed in triplicate. *, P < 0.05 (compared with wild-type M. avium subsp. paratuberculosis intracellular Fe:Mg ratio).