Dictyostelium discoideum or cellular slime mold is simple eukaryotic microorganism, which generally grows in forest soil and decaying leaves. This amoeba feeds on bacteria and grows as single cells. The development of Dictyostelium discoideum is simpler than that of mammalian cells. It uses many of the same signals that are found to function in higher eukaryotic organisms like plants and animals. Dictyostelium discoideum is an excellent system in which to study metabolic pathways which are simpler than that of the complex systems like mammalian system. Glucose is metabolized in glycolysis to yield pyruvate and lactate and further metabolized in the tricarboxylic acid cycle. Glucose can be polymerized into glycogen in addition to glycolysis process. In a metabolic pathway, the generation of glucose from certain non‐carbohydrate carbon substrates is called gluconeogenesis. In Dictyostelium discoideum, glucose is synthesized by the breakdown of pyruvate. Glycogen phosphorylase and amylase break down glycogen to form glucose. Glycogen synthase and glycogen phosphorylase are the key enzymes for the regulation. Both the enzyme equally regulated the process simultaneously, so that when one is activated, the other is deactivated. During gluconeogenesis, glucose is synthesized from pyruvate but sometimes during this process, three enzymes, glucose‐6‐phophatase, fructose‐1,6‐bisphosphatase, and phosphoenolpyruvate carboxykinase catalyze an irreversible reaction.
Part of the book: Gluconeogenesis