Structural highlights
Disease
[PYGL_HUMAN] Defects in PYGL are the cause of glycogen storage disease type 6 (GSD6) [MIM:232700]. A metabolic disorder characterized by mild to moderate hypoglycemia, mild ketosis, growth retardation, and prominent hepatomegaly. Heart and skeletal muscle are not affected.[1]
Function
[PYGL_HUMAN] Phosphorylase is an important allosteric enzyme in carbohydrate metabolism. Enzymes from different sources differ in their regulatory mechanisms and in their natural substrates. However, all known phosphorylases share catalytic and structural properties.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Glycogen phosphorylases catalyze the breakdown of glycogen to glucose-1-phosphate, which enters glycolysis to fulfill the energetic requirements of the organism. Maintaining control of blood glucose levels is critical in minimizing the debilitating effects of diabetes, making liver glycogen phosphorylase a potential therapeutic target. To support inhibitor design, we determined the crystal structures of the active and inactive forms of human liver glycogen phosphorylase a. During activation, forty residues of the catalytic site undergo order/disorder transitions, changes in secondary structure, or packing to reorganize the catalytic site for substrate binding and catalysis. Knowing the inactive and active conformations of the liver enzyme and how each differs from its counterpart in muscle phosphorylase provides the basis for designing inhibitors that bind preferentially to the inactive conformation of the liver isozyme.
Activation of human liver glycogen phosphorylase by alteration of the secondary structure and packing of the catalytic core.,Rath VL, Ammirati M, LeMotte PK, Fennell KF, Mansour MN, Danley DE, Hynes TR, Schulte GK, Wasilko DJ, Pandit J Mol Cell. 2000 Jul;6(1):139-48. PMID:10949035[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Burwinkel B, Bakker HD, Herschkovitz E, Moses SW, Shin YS, Kilimann MW. Mutations in the liver glycogen phosphorylase gene (PYGL) underlying glycogenosis type VI. Am J Hum Genet. 1998 Apr;62(4):785-91. PMID:9529348
- ↑ Rath VL, Ammirati M, LeMotte PK, Fennell KF, Mansour MN, Danley DE, Hynes TR, Schulte GK, Wasilko DJ, Pandit J. Activation of human liver glycogen phosphorylase by alteration of the secondary structure and packing of the catalytic core. Mol Cell. 2000 Jul;6(1):139-48. PMID:10949035
