Metabolic pathways: glycogen Flashcards
What is glycogenesis?
Synthesis of glycogen from glucose (opposite of glycogenolysis)
What is glycogenolysis?
Breakdown of glycogen to form glucose (opposite of glycogenesis)
What is gluconeogenesis?
De novo synthesis of glucose from metabolic precursors (lactate, amino acids, glycerol) (opposite of glycolysis)
What is glycogen?
Main storage form of glucose in liver and muscle cells. It is a polymer consisting of glucose molecules
What links the glucose molecules in glycogen?
Alpha 1-4 glycosidic links (branches are introduced by alpha 1-6 glycosidic links)
How are glucose residues added to glycogen?
A glycogen primer containing at least four glucose residues is required. It is covalently attached to a protein called glycogenin
What is glycogen synthase?
Enzyme that synthesizes glycogen from UDP-glucose. It adds one glucose molecule at a time and cannot start new molecules or introduce branches
What catalyzes glycogenolysis?
Glycogen phosphorylase
What is glycolysis?
Glycolysis is the metabolic pathway that converts glucose into pyruvate
