Protein Phosphatase Protocols pp 41-58
Inhibitor-1, a Regulator of Protein Phosphatase 1 Function
With the discovery of numerous eukaryotic protein serine/threonine phosphatases, a classification scheme was developed that exploited some of the biochemical properties of these enzymes to expedite their identification (1). These properties included the preferential dephosphorylation of either α or β-subunits of phosphorylase kinase, the metal ion dependency displayed by some phosphatases for enzyme activity and their inhibition by two mammalian thermostable proteins, inhibitor-1 (I-1) and inhibitor-2 (I-2).
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