Figure 4. The pH profile of the logarithm of k[cat]/K[m]
(M^-1s^-1) for hydration of CO catalyzed by H64A HCA II (
and H64A-T200H HCA II ( ).
Experimental conditions were as described in Figure 1. For
H64A-T200H HCA II the solid line is a fit to two ionizations
(Equation 6) with pK[a1] = 5.8 ± 0.4 and pK[a2] = 8.0
± 0.4. For H64A HCA II the data are fit to a single
ionization with pK[a] = 6.9 ± 0.1.
The above figure is reprinted
by permission from John Wiley & Sons, Inc.: