[The level of cytochrome P-450 in Saccharomyces cerevisiae with disruptions of various stages of sterol synthesis].

A spectral analysis of cytochromes P-450 in Saccharomyces cerevisiae cells and in mutant strains accumulating the ergosterol biosynthesis intermediates was carried out. Glucose repression and semianaerobiosis were found to induce cytochrome P-450 synthesis. No differences in the cytochrome P-450 content in mutant nys 3, nys 4 and parent strains were observed. Mutants nys 5 accumulated large amounts of cytochrome P-450. Cytochrome P-420 was detected in wild type strains and in mutants nys 3 and nys 4. The cultivation time and aeration conditions were shown to be unimportant for the generation of cytochrome P-420.