Figure 2.

Kinetic modeling of DNA adduct yields to obtain kinetic parameters. Yields of AFB diol obtained with 18 μM AFB₁ exo-8,9-epoxide and varying concentrations of DNA were fit to the model:

where A = AFB₁ exo-8,9-epoxide, D = AFB diol, B = DNA, C = DNA–AFB adduct, and k₀ was determined to be 0.60 s⁻¹ (4). K_d and k_cat were estimated by reiterative fitting with a KINSIM program (11) to give values of C that are consistent with the experimentally determined values (of C and D) found with varying concentration of A and B (12). The solid line is that for K_d = 0.43 mg ml⁻¹ (1.4 mM monomer equivalents) and k_cat = 35 s⁻¹.