Yeast protein farnesyltransferase. Binding of S-alkyl peptides and relatedanalogues

[GRAPHICS] Protein farnesyltransferase (PFTase) catalyzes alkylation of cysteine resid ues by farnesyl diphosphate (FPP), The dissociation constants for the PFTas e peptide analogue complexes for the series of analogues fl-RTRC(X)VIA (X = H, methyl, dodecyl, farnesyl) were measured by fluorescence anisotropy. Th e results indicate that an ionizable sulfhydryl moiety is important for sub strate binding and the farnesyl group in the product facilitates binding.