FIGURE 8.

Identification of conserved residues that alter isoprenylcysteine substrate binding properties. A, radioactive methyl transfer relative to wild-type enzyme for select Ag ICMT mutants assayed in the presence of 5 μm AdoMet using either 4 or 40 μm BFC. B, relative methyl transfer using 5 and 50 μm AdoMet for Ag ICMT mutants shown to be inhibited by BFC in A. C, relative methyl transfer by wild-type and F216A mutant Ag ICMT measured using the indicated substrate concentrations. For all panels, the data shown are the mean of duplicate determinations from a single experiment, with error bars representing ± 1 S.D. The amino acid numbering corresponds to Ag ICMT with Hs ICMT numbering in parentheses.