FIG. 1.

(A) Schematic representation of the late stages of the ergosterol biosynthetic pathway. erg6, erg2, erg3, erg5, and erg4 encode S-adenosyl methionine methyltransferase, C-8 sterol isomerase, sterol C-5 desaturase, C-22 sterol desaturase, and sterol-24(28) reductase, respectively. (B) Growth curves of WT (♦), erg2 (▪), erg3 (▴), erg4 (•), and erg6 (∗) strains. The specific growth rates are 1.76 h for WT, 2.01 h for erg2, 1.78 h for erg3, 1.52 h for erg4, and 1.71 h for erg6. (C) UV absorption spectra of sterols extracted from the S. cerevisiae WT strain and its erg mutants. Their absorption spectra were recorded as described in Materials and Methods.