Glycogen Structure: an Evolutionary View
Muscle glycogen is the fuel for anaerobic glycolysis, a metabolic process to obtain ATP quickly and to support rapid “explosive” movement. The polymer structure of the glycogen molecule is a very efficient way of having a large amount of stored cytoplasmic glucose without a significant increase in osmolarity. Thus, the total amount of fuel stored in liver cells as glycogen (around 10% by weight) is equivalent to 200-400 mM glucose, whereas the concentration of glycogen is only 3.6-7.2 µM. In skeletal muscle of a trained runner the concentration of glycogen is about 2 µM, equivalent to 110 mM glucose (around 1-2% by weight). The branching structure of glycogen supplies many points for phosphorylase attack, allowing the release of more glucose at the same time.
KeywordsChain Length Muscle Glycogen Glycogen Storage Disease Anaerobic Glycolysis Glucose Residue
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