title: Partial purification and characterization of phosphotyrosyl-protein phosphatase(s) from human erythrocyte cytosol.
abstract: Phosphotyrosyl-protein phosphatase activity of human erythrocyte cytosol can be resolved into two fractions by DEAE-cellulose chromatography followed by P-cellulose chromatography. Both 32P-Tyr-phosphatases are able to dephosphorylate 32P-Tyr of poly (Glu-Tyr) 4:1 but not angiotensin II and synthetic peptide Asp-Ala-Glu-Tyr-Ala-Ala-Arg-Arg-Gly, previously phosphorylated on tyrosine residues by rat spleen tyrosine-protein kinase. Both 32P-Tyr-phosphatase activities distinctly differ from either 32P-Ser-casein phosphatase activity or "acid" and "alkaline" p-nitrophenylphosphatase activities with regard to catalytic and physico-chemical properties such as substrate specificity, chromatographic behaviour, response to various effectors.
mesh_terms: D009597:4-Nitrophenylphosphatase / Q000097:blood; D002848:Chromatography, DEAE-Cellulose; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans; D010749:Phosphoprotein Phosphatases / Q000097:blood*; D019000:Phosphotyrosine; D013379:Substrate Specificity; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism
chemical_list: D019000:Phosphotyrosine; D014443:Tyrosine; D010749:Phosphoprotein Phosphatases; D009597:4-Nitrophenylphosphatase