Glycogen phosphorylase is one of the phosphorylaseenzymes（EC2.4.1.1). It breaks up glycogeninto glucosesubunits. Glycogenis left with one less glucosemolecule， and the free glucosemolecule is in the form of glucose-1-phosphate. In order to be used for metabolism， it must be converted to glucose-6-phosphateby the enzyme phosphoglucomutase.
Glycogen phosphorylase can only act on linearchainsof glycogen（a 1-4 glycosidic linkage). Its work will immediately come to a halt four residues away from a 1-6 branch（which are exceedingly common in glycogen). In these situations， a debranching enzymeis necessary， which will straighten out the chain in that area. Additionally， an alpha 1-6 glucosidaseenzymeis required to break the remaining 1-6 residue that remains in the new linear chain. After all this is done， glycogen phosphorylase can continue.
An insulinstimulated enzyme known as phosphoprotein phosphatase（PP-1) inactivates glycogen phosphorylase to prevent glycogen break up.
GPBB - a sensitive marker for the AMI diagnosis within 4 hours after the onset of chest pain. It has also been shown that GPBB is increased in a considerable proportion of AMI patients within 2-3 hours from chest pain onset. GPBB is increased early in patients with unstable angina. GPBB can also be a sensitive marker for the detection of peri-operative myocardial ischaemia and infarction in patients undergoing coronary artery bypass grafting.
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該【GPBB】重組人糖原磷酸化酶Recombinant Human Glycogen Phosphorylase是Prospec品牌中國區域代理商艾美捷科技產品，具體的蛋白序列可查看提供的英文版本產品說明書。
