Figure 4.

P472L mutation increases D2 ATPase activity and alters its intra-subunit control by D1. A, schematic shows the location of the P472L mutation relative to Walker A and Walker B mutations in D1 and D2. B, ATP titration experiments (n = 4, S.D. error) were performed to obtain steady-state kinetic parameters of p97 and the P472L mutant proteins containing the indicated Walker motif mutations. The sensitivities of the ATPase activities of p97 and the P472L mutant with Walker motif mutations in D1 or D2 were evaluated in the presence of increasing concentrations of CB-5083 (C) and NMS-873 (D) (n = 4, S.D. error). Resulting kinetic properties and IC₅₀ values are summarized in Table 2.