Effect of Triparanol on Synthesis of Squalene and Tetrahymanol by Tetrahymena pyriformis

In triparanol-inhibited cultures of T. pyriformis (strains W, H and S), squalene is greatly increased in amount and tetra-hymanol is decreased. In contrast, squalene appears in low concentration in uninhibited cultures. It appears that squalene might be converted directly to the pentacyclic compound, tetrahymanol, and that the cyclization of squalene is blocked by triparanol. Cholesterol was not identified in control or inhibited cultures and appears neither to be a sterol of major importance in this organism, nor an intermediate in the synthesis of tetrahymanol. Methods of purification and identification of tetrahymanol are given.