Figure 3 - full size

 

Figure 3.
Fig. 3. The pH dependence of R[H2O]/[E] (ms 1) catalyzed by wild type HCA III ( ), K64H HCA III ( ), R67H HCA III ( ), and the double mutant K64H/R67H HCA III ( circle ). The values were determined by 18O exchange at 25 °C using solutions containing no buffers; ionic strength of solution was maintained at 0.2 M by addition of Na[2]SO[4]. The lines are least squares fits of Equation 6 to the data yielding the values of pK[a] of the donor and acceptor groups and the values of k[B] given in Table IV.

The above figure is reprinted by permission from the ASBMB: J Biol Chem (2002, 277, 38870-38876) copyright 2002.