HOMOGENEOUS ASSAY FOR KINASE AND PHOSPHATASE ACTIVITY

摘要

This invention relates to a peptide substrate comprising one or more phosphorylated and/or phosphorylatable amino acids and labelled with a fluorescent lanthanide chelate wherein the fluorescence of the lanthanide chelate changes depending on the degree of phosphorylation of the peptide substrate. This invention also relates to a method for determining protein kinase activity wherein the peptide substrate of the invention acts as a substrate of a protein Kinase or phosphatase and wherein the determination of said protein kinase or phosphatase activity is based on that the fluorescence of the lanthanide chelate changes when one or more phosphorous groups are added or removed, respectively, to said peptide substrate. The invention further relates to the use of the methods of the invention for screening of compounds for inhibition or activation of protein kinase activity or protein phosphatase activity.