Biomaterial Database

Differential membrane protein carboxyl-methylation of intact human erythrocytes by exogenous methyl donors. 1984

J Y Ro, and P DiMaria, and S Kim

The patterns of membrane protein carboxyl-methylation by protein methylase II (S-adenosylmethionine: protein-carboxyl O-methyltransferase, EC 2.1.1.24) in intact human erythrocytes were shown to differ markedly whether the methyl donor, S-adenosyl-L-[methyl-3H]methionine, was supplied exogenously or formed intracellularly via exogenously added L-[methyl-3H]methionine. The differences include the following. (1) The methylation of cytoskeletal components (band 2.1 and 4.1) occurs only in the case of the L-[methyl-3H]methionine-labelled cells. (2) The methionine-mediated methylation was much less sensitive to S-adenosyl-L-homocysteine inhibition than the adenosylmethionine-mediated methylation (22% versus 95% inhibition at 10 microM). (3) The membrane protein methylation mediated by exogenous adenosylmethionine and methionine differed markedly in their alkali labilities; at pH 6.0, 30% of the adenosylmethionine-mediated protein methyl esters were hydrolysed after 30 min (37 degrees C) while the methionine-mediated esters were stable. At pH 7.4, the respective labilities were 60% and 30% for the 30 min incubation. To explain these results, a possible involvement of cytoskeletal structure associated with the intact erythrocyte is discussed.

UI	MeSH Term	Description	Entries
D008565	Membrane Proteins	Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.	Cell Membrane Protein,Cell Membrane Proteins,Cell Surface Protein,Cell Surface Proteins,Integral Membrane Proteins,Membrane-Associated Protein,Surface Protein,Surface Proteins,Integral Membrane Protein,Membrane Protein,Membrane-Associated Proteins,Membrane Associated Protein,Membrane Associated Proteins,Membrane Protein, Cell,Membrane Protein, Integral,Membrane Proteins, Integral,Protein, Cell Membrane,Protein, Cell Surface,Protein, Integral Membrane,Protein, Membrane,Protein, Membrane-Associated,Protein, Surface,Proteins, Cell Membrane,Proteins, Cell Surface,Proteins, Integral Membrane,Proteins, Membrane,Proteins, Membrane-Associated,Proteins, Surface,Surface Protein, Cell
D008715	Methionine	A sulfur-containing essential L-amino acid that is important in many body functions.	L-Methionine,Liquimeth,Methionine, L-Isomer,Pedameth,L-Isomer Methionine,Methionine, L Isomer
D008745	Methylation	Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed)	Methylations
D011497	Protein O-Methyltransferase	An enzyme that catalyzes the transfer of methyl groups from S-adenosylmethionine to free carboxyl groups of a protein molecule forming methyl esters. EC 2.1.1.-.	Protein Carboxylmethyltransferase,Protein Methylase II,Protein Methyltransferase II,Protein Carboxyl-Methylase,Protein Carboxymethylase,Protein O-Carboxymethyltransferase,Protein-Glutamic(Aspartic)-Methyltransferase,S-Adenosylmethionine Protein Carboxymethyltransferase,S-Adenosylmethionine Protein O-Methyltransferase,S-Adenosylmethionine-Protein Carboxymethyl Transferase,Carboxyl-Methylase, Protein,Carboxylmethyltransferase, Protein,Carboxymethyl Transferase, S-Adenosylmethionine-Protein,Carboxymethylase, Protein,Carboxymethyltransferase, S-Adenosylmethionine Protein,Methylase II, Protein,Methyltransferase II, Protein,O-Carboxymethyltransferase, Protein,O-Methyltransferase, Protein,O-Methyltransferase, S-Adenosylmethionine Protein,Protein Carboxyl Methylase,Protein Carboxymethyltransferase, S-Adenosylmethionine,Protein O Carboxymethyltransferase,Protein O Methyltransferase,Protein O-Methyltransferase, S-Adenosylmethionine,S Adenosylmethionine Protein Carboxymethyl Transferase,S Adenosylmethionine Protein Carboxymethyltransferase,S Adenosylmethionine Protein O Methyltransferase,Transferase, S-Adenosylmethionine-Protein Carboxymethyl
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D004910	Erythrocyte Membrane	The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.	Erythrocyte Ghost,Red Cell Cytoskeleton,Red Cell Ghost,Erythrocyte Cytoskeleton,Cytoskeleton, Erythrocyte,Cytoskeleton, Red Cell,Erythrocyte Cytoskeletons,Erythrocyte Ghosts,Erythrocyte Membranes,Ghost, Erythrocyte,Ghost, Red Cell,Membrane, Erythrocyte,Red Cell Cytoskeletons,Red Cell Ghosts
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006868	Hydrolysis	The process of cleaving a chemical compound by the addition of a molecule of water.
D012435	S-Adenosylhomocysteine	5'-S-(3-Amino-3-carboxypropyl)-5'-thioadenosine. Formed from S-adenosylmethionine after transmethylation reactions.	S Adenosylhomocysteine,Adenosylhomocysteine, S
D012436	S-Adenosylmethionine	Physiologic methyl radical donor involved in enzymatic transmethylation reactions and present in all living organisms. It possesses anti-inflammatory activity and has been used in treatment of chronic liver disease. (From Merck, 11th ed)	AdoMet,Ademetionine,FO-1561,Gumbaral,S Amet,S-Adenosyl-L-Methionine,S-Adenosylmethionine Sulfate Tosylate,SAM-e,Samyr,FO 1561,FO1561,S Adenosyl L Methionine,S Adenosylmethionine,S Adenosylmethionine Sulfate Tosylate