Lanosterol

TL;DR: Enzymatic Δ8 → Δ7 isomerization of methyl intermediates of lanosterol demethylation may occur, but the rate of isomersization may not be significant until later stages of dem methylation are reached.

TL;DR: With [3H-24,25]-dihydrolanosterol as substrate, large-scale metabolic formation of intermediates of lanosterol demethylation was carried out to identify all compounds in the metabolic process and characterized by ultraviolet, 1H-NMR, and infrared spectroscopy of the isolated sterols.

TL;DR: Findings indicate that unlike Scap, fission yeast Scp1 responds to 4- methyl sterols and thus shares properties with mammalian HMG-CoA reductase, a sterol-sensing domain protein whose degradation is regulated by the 4-methyl sterol lanosterol.

TL;DR: It is concluded that cytochrome P-450 and a cyanide-sensitive enzyme are involved in the 14α- and 4-demethylations of lanosterol, respectively, by yeast microsomes.

TL;DR: These findings demonstrate that two separate isoprenoid-24-alkyl sterol pathways evolved in fungi and green algae, both of which converge to yield a common membrane insert ergosterol.