Intracellular cAMP Content and the Induction of Alternative Oxidase in the Yeast Yarrowia lipolytica

The effect of cyanide, antimycin A, ethanol, and acetate on the induction of alternative oxidase in the yeast Yarrowia lipolytica VKM Y-155 was studied. The aerobic incubation of logarithmic-phase cells, whose respiration is sensitive to cyanide, in the presence of the aforementioned compounds led to the development of cyanide-resistant respiration, which could be suppressed by benzohydroxamic acid, an inhibitor of alternative oxidases. The incubation of cells with cyanide, ethanol, or acetate raised the intracellular pool of cAMP, which attained maximal values after a 2- to 3-min incubation period, then rapidly decreased to the initial value and did not change over the next three hours of incubation. The possible role of cAMP in the induction of alternative oxidase in yeast cells is discussed.