EFFECT OF CARBON SOURCE ON THE ACCUMULATION OF CYTOCHROME-P-450 AND CYTOCHROME-C IN THE YEAST RHODOSPORIDIUM TORULOIDES

The appearance of cytochrome content in the yeast Rhodosporidium toruloides depended on the substrate supporting growth. The cells of R. toruloides growing on benzoate were found to contain cytochrome P-450. The concentration of cytochrome P-450 was maximal at the beginning of the exponential phase and then remained at a relatively constant level, but rapidly decreased at the beginning of the stationary phase. When benzoate was exhausted from the medium, the cytochrome P-450 level decreased to zero. On the other hand, cytochrome P-450 was not detected when R. toruloides grew on glucose. However, cytochrome P-450 was detected, when R. toruloides was grown on benzoate together with glucose. The maximal content of cytochrome c in the cells was observed at the beginning of the exponential phase of growth on both substrates and decreased most rapidly during late stationary phase of growth. The content of cytochrome c in R. toruloides was 2-3 times lower during the growth on glucose as compared to the growth on benzoate.