ATP-citrate lyase activity in fungal extracts

ATP-citrate lyase activity has been demonstrated in crude extracts from several species ofMortierella. This filamentous fungus characteristically stores lipid in the mycelium. The enzyme catalyses an ATP-dependent cleavage of citrate in the presence of CoA to oxaloacetic acid and acetylCoA. A partially purified preparation has been obtained and shown to have properties similar to preparations isolated from other sources. It is highly specific for citrate and ATP and has an optimum pH value for activity of 8.4. When the fungus is grown in the presence of increasing amounts of glucose the specific activity of the enzyme also increases.