Biosynthesis of (+)-cis- and (+)-trans-sabinene hydrate from geranyl pyrophosphate by a soluble enzyme system from sweet marjoram (Majorana hortensis)

Thesis/Dissertation · Fri Jan 01 00:00:00 EST 1988

OSTI ID:7246026

Hallahan, T W

A soluble enzyme preparation from the leaves of sweet marjoram (Majorana hortensis Moench) catalyzes the divalent cation-dependent cyclization of (1-{sup 3}H)geranyl pyrophosphate to the bicyclic monoterpene alcohols (+)-cis- and (+)-trans-(6{sup 3}H)sabinene hydrate, providing labeling patterns consistent with current mechanistic considerations. The two enzymatic activities were inseparable by several chromatographic procedures, and differential inactivation studies suggesting that the two activities reside with the same enzyme. The enzymatic cyclization is considered to proceed by the initial ionization and isomerization of geranyl pyrophosphate to (-)-(3R)-linalyl pyrophosphate and the subsequent cyclization of this enzyme bound tertiary allylic intermediate to the monocyclic (+)-(4R)-{alpha}-terpinyl cation. A 1,2-hydride shift and a second cyclization with water capture of the resulting cation completes the reaction sequence. No free intermediates were detectable in the conversion of geranyl pyrophosphate to the sabinene hydrates as determined by isotopic dilution experiments.

• Research Organization: Washington State Univ., Pullman, WA (USA)
• OSTI ID: 7246026
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CYCLASES
ENZYME ACTIVITY
PYROPHOSPHATES
METABOLISM
TERPENES
BIOSYNTHESIS
CHROMATOGRAPHY
ISOTOPE DILUTION
LEAVES
TRITIUM COMPOUNDS
ENZYMES
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
LYASES
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PHOSPHORUS COMPOUNDS
SEPARATION PROCESSES
SYNTHESIS
TRACER TECHNIQUES
550201* - Biochemistry- Tracer Techniques