Biosynthèse du squalène dans un système acellulaire obtenu à partir de tissus de tabac cultivés in vitro

Abstract

Squalene and farnesol are identified as products arising from 2- 14C mevalonic acid in a cell-free system from tobacco tissues grown in vitro. This system is composed of a soluble fraction, which is involved in the synthesis of farnesyl pyrophosphate, and microsomes which are necessary to synthesize squalene from the latter compound. Squalene is obtained only when the incubation mixture contained ATP, NADH, a metallic divalent cation and thiols. Mn ++ is shown to be more active than Mg ++. No products following squalene in the sterol pathway are detected.