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Updated: Jan 4, 2026

Spectrophotometric Methods for the Study of Eukaryotic Glycogen Metabolism
Published on: August 19, 2021
Are cysteines present at the active site of glycogen phosphorylase?
Abstract:
Periodate and the anions of the transitional elements inactivate glycogen phosphorylase with resolution of the coenzyme from the active site. The effects of the ionic strength and pH of the incubation mixture on the rate of inactivation allow to discriminate between the actions of these chemicals, suggesting that they recognize different regions at the enzyme active site. This conclusion is in agreement with the identification of cysteine as the target amino acid for the inactivation by periodate while arginine was reported to be responsible for the vanadate mediated inactivation.
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