Human Erythrocyte D-Aspartyl/L-Isoaspartyl Methyltransferases: Enzymes that Recognize Age-Damaged Proteins
Among the large number of protein post-biosynthetic modifications described so far are a group of non-enzymatic reactions that reflect the spontaneous, intrinsic, decomposition of these macromolecules as they age in cells. These alterations include oxidation (1), formation of advanced glycosylation end products (2), and linked deamination/isomerization/ racemization reactions (3). Our interest has been focused on the latter reactions that lead to the loss of L-aspartyl and L-asparaginyl residues in proteins and the recognition of the damaged proteins by enzymes that can lead to their cellular removal by repair or degradation reactions (4–9).
KeywordsHuman Erythrocyte Methyl Transferase Isopeptide Bond Aspartyl Residue Protein Carboxyl
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