Glycogen Metabolism

Each list begins with basic conceptual vocabulary you need to know for MCAT questions and proceeds to advanced terms that might appear in context in MCAT passages. The terms are links to Wikipedia articles.
Glycogen synthase
A key enzyme in glycogenesis, glycogen synthase is a glycosyltransferase that catalyses the reaction of UDP-glucose and (1,4-α-D-glucosyl)n to yield UDP and (1,4-α-D-glucosyl)n+1.
Glycogen phosphorylase
Glycogen phosphorylase catalyzes the rate-limiting step in glycogenolysis in animals by releasing glucose-1-phosphate from the terminal alpha-1,4-glycosidic bond.
Glycogenesis is the process of glycogen synthesis, in which glucose molecules are added to chains of glycogen.
Phosphorolysis is the cleavage of a compound in which inorganic phosphate is the attacking group.
Glycogenolysis is the catabolism of glycogen by removal of a glucose monomer and addition of phosphate to produce glucose-1-phosphate.
Glycogenin is an enzyme involved in converting glucose to glycogen. It acts as a primer, by polymerizing the first few glucose molecules, after which other enzymes take over.
Glycogen debranching enzyme
Glycogen debranching enzyme is a molecule that helps facilitate the breakdown of glycogen, which serves as a store of glucose in the body, through glucosyltransferase and glucosidase activity.
Glycogen branching enzyme
Glycogen branching enzyme is an enzyme that adds branches to the growing glycogen molecule during the synthesis of glycogen.
Glycogen storage disease
A glycogen storage disease is a metabolic disorder caused by enzyme deficiencies affecting either glycogen synthesis, glycogen breakdown or glycolysis (glucose breakdown), typically in muscles and/or liver cells.
Phosphorylase kinase
Phosphorylase kinase (PhK) is a serine/threonine-specific protein kinase which activates glycogen phosphorylase to release glucose-1-phosphate from glycogen.
Protein phosphatase 1
Protein phosphatase 1 plays a crucial role in the regulation of blood-glucose levels in the liver and glycogen metabolism by ensuring the opposite regulation of glycogen breakdown and glycogen synthesis.
Uridine diphosphate glucose
Uridine diphosphate glucose is a nucleotide that is used as an activated form of glucose, a substrate for glycosyltransferases.
Cori ester
Glucose 1-phosphate (also called cori ester) is a glucose molecule with a phosphate group on the 1'-carbon.
Phosphoglucomutase is an enzyme that transfers a phosphate group on an α-D-glucose monomer from the 1 to the 6 position in the forward direction or the 6 to the 1 position in the reverse direction.

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