Metabolism of monoterpenes: demonstration of the hydroxylation of (+)-sabinene to (+)-cis-sabinol by an enzyme preparation from sage (Salvia officinalis) leaves.
A microsomal preparation from the epidermis of Salvia officinalis leaves catalyzed the NADPH- and O2-dependent hydroxylation of the monoterpene olefin (+)-sabinene to (+)-cis-sabinol. The reaction catalyzed is a key step in the biosynthesis of C3-oxygenated thujane monoterpenes, and the hydroxylase is highly specific for (+)-sabinene as substrate. The hydroxylase from leaf homogenates was solubilized and characterized with regard to reaction conditions, inhibitors, and activators. Activity was partially inhibited by rabbit anti-rat cytochrome P-450 and by CO, and the latter inhibition was reversed by 450 nm light. A CO-difference spectrum and type I substrate binding spectrum were obtained. The hydroxylase meets most of the established criteria for a cytochrome P-450-dependent mixed function oxygenase and represents one of very few enzyme systems of this type to be isolated from leaves of a higher plant.
D000081008:Bicyclic Monoterpenes; D002248:Carbon Monoxide / Q000494:pharmacology; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D006900:Hydroxylation; D008861:Microsomes / Q000378:metabolism; D006899:Mixed Function Oxygenases / Q000037:antagonists & inhibitors / Q000378:metabolism; D039821:Monoterpenes; D009251:NADPH-Ferrihemoprotein Reductase / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism; D010944:Plants / Q000201:enzymology / Q000378:metabolism*; D012995:Solubility; D013379:Substrate Specificity; D013729:Terpenes / Q000096:biosynthesis* / Q000378:metabolism*
D000081008:Bicyclic Monoterpenes; D039821:Monoterpenes; D010743:Phospholipids; D013729:Terpenes; C052984:sabinol; C035127:sabinene; D002248:Carbon Monoxide; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D009251:NADPH-Ferrihemoprotein Reductase