EC Explorer

4.2.3.119

(-)-α-pinene synthase

geranyl diphosphate = (-)-α-pinene + diphosphate

(-)-α-pinene/(-)-camphene synthase, (-)-α-pinene cyclase

geranyl-diphosphate diphosphate-lyase [cyclizing, (-)-α-pinene-forming]

Cyclase II of Salvia officinalis (sage) gives about equal parts (-)-α-pinene, (-)-β-pinene and (-)-camphene, plus traces of other monoterpenoids. (3S)-Linalyl diphosphate can also be used by the enzyme in preference to (3R)-linalyl diphosphate. The 4-pro-S-hydrogen of geranyl diphosphate is lost. Requires Mg²⁺ (preferred to Mn²⁺) [1-6]. The enzyme from Abies grandis (grand fir) gives roughly equal parts (-)-α-pinene and (-)-β-pinene. However the clone ag11 gave 35% (-)-limonene, 24% (-)-α-pinene and 20% (-)-β-phellandrene. It requires Mn²⁺ and K⁺ (Mg²⁺ is ineffective) [7-10]. Synthase I from Pinus taeda (loblolly pine) produces (-)-α-pinene with traces of (-)-β-pinene and requires Mn²⁺ (preferred to Mg²⁺) [11,12]. The enzyme from Picea sitchensis (Sika spruce) forms 70% (-)-α-pinene and 30% (-)-β-pinene [13]. The recombinant PmeTPS1 enzyme from Pseudotsuga menziesii (Douglas fir) gave roughly equal proportions of (-)-α-pinene and (-)-camphene plus traces of other monoterpenoids [14]. See also EC 4.2.3.120, (-)-β-pinene synthase; EC 4.2.3.117, (-)-camphene synthase; EC 4.2.3.16, (-)-limonene synthase; and EC 4.2.3.52, (-)-β-phellandrene synthase.

created 2012