We have isolated the gene for cytochrome P450 lanosterol 14 alpha-demethylase (14DM) from the yeast Candida tropicalis. This was accomplished by screening genomic libraries of strain ATCC750 in E. coli using a DNA fragment containing the yeast Saccharomyces cerevisiae 14DM gene. Identity of this gene was confirmed by a) observing a heme binding region common to all P450s after sequencing the 3' portion of the gene, and b) based upon tests of its expression in strains of Saccharomyces cerevisiae.