Substrate specificities of farnesyl diphosphate synthases with respect to cyclic substrate homologs

Abstract

We investigated substrate specificities of farnesyl diphosphate synthases (FPSs) derived from porcine liver and Bacillus stearothermophilus by examining the reactivity of cyclopentylideneethyl diphosphate with several 3-alkyl homologs of isopentenyl diphosphate. Reaction of cyclopentylideneethyl diphosphate with isopentenyl diphosphate using porcine liver or bacterial enzyme gave 10-cyclopentyliden-3,7-dimethyldeca-2,6-dinenyl diphosphate as a double condensation product, with relative yields of 40.9% for the porcine liver enzyme and 15.9% for the bacterial enzyme. Reaction of cyclohexlideneethyl diphosphate with 3-ethylbut-3-enyl diphosphate using the bacterial enzyme gave 10-cyclohexliden-3,7-diethyldeca-2,6-dinenyl diphosphate (yield: 24.6%).