Glycogen phosphorylase concentration, as the liver acts as a glucose exporter. In essence, liver phosphorylase is responsive to glucose, which causes a very responsive transition from the R to T form, inactivating it; furthermore, liver phosphorylase is insensitive to AMP. Glycogen phosphorylase was the first allosteric enzyme to be discovered. This accomplishment was one of many landmark achievements made by Carl and Gerty Cori. In 1943, with the help of Arda Green, the pair illustrated that glycogen phosphorylase existed in either the or b forms depending on its phosphorylation state, as well as in the R or T states based on the
(glycogen-synthase-D) phosphatase (glycogen-synthase-D) phosphatase In enzymology, a [glycogen-synthase-D] phosphatase () is an enzyme that catalyzes the chemical reaction Thus, the two substrates of this enzyme are glycogen-synthase D and HO, whereas its two products are glycogen-synthase I and phosphate. This enzyme belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name of this enzyme class is [UDP-glucose:glycogen 4-alpha-D-glucosyltransferase-D] phosphohydrolase. Other names in common use include uridine diphosphoglucose-glycogen glucosyltransferase phosphatase, UDP-glycogen glucosyltransferase phosphatase, UDPglucose-glycogen glucosyltransferase phosphatase, glycogen glucosyltransferase phosphatase, glycogen synthetase phosphatase, glycogen synthase phosphatase, glycogen synthase D phosphatase, Mg dependent glycogen synthase phosphatase, and phosphatase type