| abstract |
This invention relates to the production of 7-dehydrocholesterol, 25-hydroxy-7-dehydrocholesterol, and 25-hydroxy ergosterol in yeast such as Saccharomyces cerevisiae . It also relates to various enzymes catalyzing the reduction of the double bond at position 24 of lanosterol, dimethyl zymosterol, methyl zymosterol, zymosterol, cholesta-7, 24-dienol, or cholesta-5,7,24-trienol; or the hydroxylation at position 25 of ergosterol, 7-dehydrocholesterol, cholesta-8-enol, and cholesta-7-enol. It also relates to various nucleic acids encoding cholesterol C25-hydroxylases and sterol Δ24-reductases and their use to produce and hydroxylate 7-dehydrocholesterol or ergosterol. It also relates to the yeast strains so produced, and methods of making these sterols that include the steps of cultivaton a transformed yeast cell, and harvesting the resulting sterol(s). |