Figure 2.

Sterol biosynthesis in proliferating TBY-2 cells: changes in cell mass (A), sterol enzyme activities (B), and free 4-demethylsterol levels (C) as a function of time after subculturing. Microsomal membranes were prepared from cultures collected on the designated days after subculturing and used for both measurements of sterol enzyme activities (the values are the means of two replicates and are representative of a standard experiment) and free 4-demethylsterol contents (±se). SMT1, S-adenosyl Met-cycloartenol methyltransferase; and SMT2, S-adenosyl Met-24-methylenelophenol methyltransferase.