Yeast killer factor: ATP leakage and coordinate inhibition of macromolecular synthesis in sensitive cells

Abstract

The action of the yeast killer factor proteins on sensitive yeast cells has been examined. The killer factor caused a coordinate inhibition of protein synthesis, nucleic acid synthesis and d-[ 4C]glucose incorporation into macromolecules in growing sensitive cells. During the inhibition period ATP became detectable in the growth medium and the cellular ATP pool level fell to exhaustion. ATP synthesis continued over this period as extracellular ATP accumulated to levels 4–20-fold those found in the cellular pools of control cultures. Leakage studies on other cellular components over the ATP leakage period indicated little loss of macromolecules, but an increased efflux of pools of leucine and glucose. The results are consistent with a killer-induced alteration in the yeast cell membrane.