title: Selective methyl esterification of erythrocyte membrane proteins by protein methylase II.
abstract: Methyl esterification of erythrocyte membrane proteins have been demonstrated by incubating the isolated membrane with purified protein methylase II (S-adenosyl-methionine:protein-carboxyl O-methyltransferase, EC 2.1.1.24) and S-adenosyl-L-[methyl-14C]methionine. Methyl esterification of membrane-bound proteins occurred selectively to proteins corresponding to bands 3 (mol wt 97 000), 4 (mol wt 75 000), and 4.5 (mol wt 48 000) [designated according to Steck, T. L. (1974), J. Cell Biol. 62, 1] as identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Mild alkali treated depleted vesicles which lacked bands 1, 2, 5, and 6 had a higher methyl accepting capacity; 500 pmol of methyl groups/mg of depleted vesicle proteins vs. 200 pmol of methyl groups/mg of intact membrane proteins. Alkali-extractable membrane components were not methylated.
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology; D002417:Cattle; D004910:Erythrocyte Membrane / Q000378:metabolism*; D004912:Erythrocytes / Q000378:metabolism*; D004952:Esters; D007700:Kinetics; D008565:Membrane Proteins / Q000097:blood*; D008745:Methylation; D011496:Protein Methyltransferases / Q000378:metabolism*; D011497:Protein O-Methyltransferase / Q000378:metabolism*; D051381:Rats; D012260:Ribonucleases
chemical_list: D004952:Esters; D008565:Membrane Proteins; D011496:Protein Methyltransferases; D011497:Protein O-Methyltransferase; D012260:Ribonucleases