Patent ID: 7608421

Claim:
A method for preparing 7-dehydrocholesterol and/or cholesterol by culturing yeast organisms which, compared to the wild type, have an increased activity of at least one of the activities selected from the group consisting of Δ8-Δ7-isomerase activity consisting of the enzymatic activity of Δ8-Δ7-isomerase having the amino acid sequence of SEQ ID.NO:2, 4 or 6, Δ5-desaturase activity consisting of the enzymatic activity of Δ5-desaturase having the amino acid sequence of SEQ ID.NO:8, 10 or 12 and Δ24-reductase activity consisting of the enzymatic activity of Δ24-reductase having the amino acid sequence of SEQ ID.NO: 14, 16 or 18 wherein the organisms additionally have increased activity of HMG-CoA-reductase obtained by gene expression of the nucleic acid sequence of SEQ.ID.NO: 23, harvesting the organisms after culturing and then isolating 7-dehydrocholesterol and/or cholesterol from said organisms.