Title: | "Purification and characterization of S-linalool synthase, an enzyme involved in the production of floral scent in Clarkia breweri" |
Author(s): | Pichersky E; Lewinsohn E; Croteau R; |
Address: | "Biology Department, University of Michigan, Ann Arbor 48109" |
ISSN/ISBN: | 0003-9861 (Print) 0003-9861 (Linking) |
Abstract: | "S-Linalool is one of the volatiles emitted by Clarkia breweri Grey [Green] flowers to attract its moth pollinator. S-Linalool synthase, the enzyme that stereoselectively converts the ubiquitous C10 intermediate GPP to S-linalool, is abundant in stigmata of freshly opened flowers, and it was purified to > 95% homogeneity by anion-exchange and hydroxyapatite chromatography. S-Linalool synthase is operationally soluble as are other monoterpene synthases, has a Km of 0.9 microM for geranyl pyrophosphate, exhibits a strict requirement for a divalent metal cofactor with a preference for Mn2+ (Km = 45 microM), and shows an optimal pH of 7.4. The enzyme is active as a monomer of 76 +/- 3 kDa as determined by gel permeation chromatography and polyacrylamide gel electrophoresis. Neither S- nor R-linalyl pyrophosphates are substrates for the C. breweri S-linalool synthase, although this tertiary allylic pyrophosphate ester is a bound intermediate in the biosynthesis of cyclic monoterpenes from geranyl pyrophosphate in many plant species, where it also serves as an alternate substrate" |
Keywords: | Acyclic Monoterpenes Hydro-Lyases/isolation & purification/*metabolism *Monoterpenes Odorants Plant Shoots/*enzymology Polyisoprenyl Phosphates/*metabolism Stereoisomerism Substrate Specificity Terpenes/*metabolism; |
Notes: | "MedlinePichersky, E Lewinsohn, E Croteau, R eng GM 31359/GM/NIGMS NIH HHS/ Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. 1995/02/01 Arch Biochem Biophys. 1995 Feb 1; 316(2):803-7. doi: 10.1006/abbi.1995.1107" |