Inhibition of growth by TPEN is rescued by the addition of Zn²⁺ ions.

(A) Susceptibility to Zn²⁺ starvation of wild type, ΔadcA and Δlmb null mutants grown in THY medium containing increasing concentrations of the chelating agent TPEN. (B) Inhibition of growth by 50 μM TPEN is rescued by the addition of either 50 μM Zn²⁺ in wild type as well as in ΔadcA and Δlmb null mutants. Error bars represent the standard deviation.