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Updated: Jul 27, 2026

Oligopeptide Competition Assay for Phosphorylation Site Determination
Published on: May 18, 2017
Two-site phosphorylation of the phosphorylatable light chain (20-kDa light chain) of chicken gizzard myosin
Abstract:
When prepared under specified conditions chicken gizzard myosin was obtained which when incubated with ATP gave rise to a diphosphorylated as well as the monophosphorylated form of P light chain. Formation of the diphosphorylated light chain occurred more readily with these myosin preparations, but could also be obtained by prolonged incubation of the isolated whole light chain fraction with kinase preparations from rabbit skeletal and chicken gizzard muscles. Using isolated light chains as substrate the more readily formed monophosphorylated light chain contained serine phosphate while the diphosphorylated form contained serine and threonine phosphates.
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