Figure 9.

Linear free energy relationship, with slope 1.05 ± 0.07, between second-order rate constants (k_cat/K_m)_OMP for wild type and variant OMPDC-catalyzed decarboxylation of OMP and third-order rate constants (k_cat/K_m)_E•Act/K_d for the OMPDC-catalyzed reactions of the substrate pieces HP_i + EO (Scheme 2). The side chains that interact with the phosphodianion and pyrimidine ring are shown using green and red print, respectively. Literature data are used for reactions catalyzed by S154A and S154A/Q215A variants,²⁴ and by Q215A, Y217F, Q215A/Y217F and R235A variants.^{12, 13}