Interaction of acetate, glucose and growth conditions on glyconeogenesis and isocitrate lyase activity in tetrahymena

Abstract

1. 1. Incubation of shaken cultures for 3 hr with acetate had little effect on the level of isocitrate lyase or the capacity for glyconeogenesis.2. 2. Maintenance of cultures under static conditions for the same period led to an eight to tenfold increase in the enzyme and to a greatly enhanced ability to convert acetate to glycogen.3. 3. Glucose prevented most of the increase in enzyme and led to a complete loss of the capacity for glyconeogenesis.4. 4. Starved cells from non-shaken suspensions developed an increased capacity for glyconeogenesis, and the presence of acetate further increased this capacity.5. 5. Cells from suspensions shaken with acetate had a much lower capacity.6. 6. It is concluded that in Tetrahymena growth conditions are much more important than acetate in the regulation of glyconeogenesis and the synthesis of isocitrate lyase.