Identification of a site for carboxyl methylation in human alpha-globin.
The human erythrocyte protein carboxyl methyltransferase modifies unusual protein D-aspartyl and L-isoaspartyl residues which arise spontaneously from internal rearrangements accompanying asparaginyl deamidation and aspartyl isomerization. A site of methylation associated with alpha-globin in intact cells has been identified by peptide mapping of radiolabeled globin isolated from human erythrocytes previously incubated with L-[methyl-3H]methionine. The site is located in a Staphylococcus V8 peptide containing residues 1-30 of alpha-globin. Two potential sources of methylation sites are present in this sequence at Asp-t and Asn-9.
Ladino
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Worcester Foundation for Experimental Biology, Shrewsbury, MA 01545.
O'Connor
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D000596:Amino Acids / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D004912:Erythrocytes / Q000201:enzymology*; D005914:Globins / Q000378:metabolism*; D006454:Hemoglobins / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D010446:Peptide Fragments / Q000302:isolation & purification; D010449:Peptide Mapping; D011497:Protein O-Methyltransferase / Q000097:blood*; D012697:Serine Endopeptidases
D000596:Amino Acids; D006454:Hemoglobins; D010446:Peptide Fragments; D005914:Globins; D011497:Protein O-Methyltransferase; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase