Enzyme Activity Measurement for Glycogen Phosphorylase

Creative Enzymes, the most reliable contract service supplier for enzyme activity quantification, provides precise spectrophotometric activity measurement for glycogen phosphorylase to the customers. Our passion for utmost quality and unique products is only exceeded by our excellent reputation in the marketplace.

Glycogen phosphorylases (EC 2.4.1.1; GP) are a group of enzymes from different sources that act in vivo on different forms of α-1,4-D-glucans. They catalyze the regulated phosphorolysis of a α-1, 4-glycosidic bond in glycogen to yield glucose-1-phosphate to meet the energetic needs of the cell. These enzymes are highly conserved from bacteria to mammals but share no homology with other carbohydrate degrading enzymes. In mammals, glycogen phosphorylases comprise a family of three isozymes named according to the tissue of their highest abundance: liver (lGP), brain (bGP), and muscle (mGP). Glycogen phosphorylases are allosteric enzymes that are regulated by both phosphorylation of Ser14 and binding of allosteric effectors (such as AMP) that control their transition between inactive and active conformations. The enzyme is activated by phosphorylation (GPa) or by binding of AMP to the unphosphorylated form (GPb).

Additionally, glycogen phosphorylases play a pivotal role in biotechnology, biosynthesis, agriculture and medical industries. For instance, inhibition of glycogen phosphorylases is used as an effective way of treating type 2 diabetes. Moreover, the mutations in the mGP are associated with McArdle's Disease, while the mutations in the lGP are correlated with Hers' Disease. The bGP has been reported as s biomarker for gastric cancer. Besides, the enzyme is a useful marker in the regulation of glycogen metabolism and reproduction of Crassostrea gigas. Thus, glycogen phosphorylases are attracting an ever-increasing interest because of their multiple functions, and a better understanding of its catalytic mechanism will shed light on the design of new inhibitors for this enzyme.

Creative Enzymes performs and provides efficient enzyme activity measurement for glycogen phosphorylases by using spectrophotometric assays. Our research center stands out with the most advanced spectrophotometric equipment, extensive research experiences and a brilliant expert team, which all ensure the high reproducibility and accuracy of the enzyme activity assay. Through working closely with our customers, Creative Enzymes has learned that the delivery of high-quality services and products on time should always be our top priority.

Figure: The crystal structure of human brain glycogen phosphorylase.
PDB: 5IKO