FIGURE 5.

Comparison of enzymatic activity of LH3/PLOD3 wild-type and mutants affecting the second Fe²⁺ binding site. (A) Luminescence-based uncoupled (i.e., with no acceptor substrate, left) and coupled (i.e., using gelatin as acceptor substrate, right) enzymatic activity assays detecting succinate formation. Error bars represent standard deviations from average of triplicate independent experiments. Statistical evaluations based on pair sample comparisons between luminescence values for wild-type LH3 and mutants using Student’s t-test. ns, non-significant; *, p-value<0.05; **, p-value<0.01; ***, p-value<0.001; ****, p-value < 0.0001. (B) Evaluation of the uncoupled (left) and coupled (right) enzymatic activities [as in panel (A)] in presence of increasing concentrations of Fe²⁺. Error bars and statistical analyses as in panel (A).