Figure 2.

Logarithmic relationships between K_i for inhibition of wildtype and mutant forms of TIM by I^3–, and the concentration of hydrogen ion. These data were fit to eq 7 or eq 8, derived for Scheme 3, depending upon whether an upward break was observed in the profile at high pH. The kinetic parameters determined from these fits are summarized in Table 1. The values of pK_EHI determined from the position of the upward breaks are given next to the individual profiles. The data for TbbWT and the Tbb170A mutant enzyme are from reference (14).