IspH Protein of the Deoxyxylulose Phosphate Pathway: Mechanistic Studies with C 1 ‐Deuterium‐Labeled Substrate and Fluorinated Analogue

The last step of the deoxylxylulose phosphate pathway is catalyzed by IspH to synthesize two precursors for isoprenoid biosynthesis. The lack of a primary kinetic isotope effect at C1and enzymatic evaluation with a fluorinated analogue (see scheme) suggest that the C1-position is not involved in the IspH-catalyzed reaction. FldA=flavodoxin, Fpr=flavodoxin reductase, NADPH=nicotinamide adenine dinucleotide phosphate, PPi=P2O63−.