Active site labeling of a receptor-like protein tyrosine phosphatase. Export

@article{citeulike:5793481, abstract = {The inactivation of the cytoplasmic domain of rat LAR, a receptor-like protein tyrosine phosphatase (PTPase), by iodoacetate and not by iodoacetamide suggested that iodoacetate interacts in a highly selective manner with the enzyme. The data indicate that iodoacetate binds at the active site of the enzyme with a stoichiometry of 0.8 mol of iodoacetate bound per mol of rat LAR. A single [14C]iodoacetate-labeled peptide was isolated following endoproteinase Lys-C digestion of the radiolabeled PTPase. Sequence analysis of the active site labeled peptide demonstrates that Cys-1522 contains the radiolabel. This residue has been shown by site-directed mutagenesis to be essential for rat LAR activity (Pot, D. A., Woodford, T. A., Remboutsika, E., Haun, R. S., and Dixon, J. E. (1991) J. Biol. Chem. 266, 19688-19696). Iodoacetate reacts only with the first domain of this double domain PTPase. These results, for the first time, directly identify the highly reactive cysteine residue at the active site of a PTPase and highlight the ability of this residue to participate as a nucleophile in the hydrolysis of phosphate from tyrosine.}, author = {Pot, D. A. and Dixon, J. E.}, citeulike-article-id = {5793481}, citeulike-linkout-0 = {http://www.jbc.org/content/267/1/140.abstract}, citeulike-linkout-1 = {http://www.jbc.org/content/267/1/140.full.pdf}, citeulike-linkout-2 = {http://view.ncbi.nlm.nih.gov/pubmed/1730581}, citeulike-linkout-3 = {http://www.hubmed.org/display.cgi?uids=1730581}, day = {5}, journal = {Journal of Biological Chemistry}, keywords = {classic, ptp}, month = {January}, number = {1}, pages = {140--143}, posted-at = {2009-09-16 22:59:13}, priority = {2}, title = {Active site labeling of a receptor-like protein tyrosine phosphatase.}, url = {http://www.jbc.org/content/267/1/140.abstract}, volume = {267}, year = {1992} }

TY - JOUR ID - citeulike:5793481 L3 - citeulike-article-id:5793481 N2 - The inactivation of the cytoplasmic domain of rat LAR, a receptor-like protein tyrosine phosphatase (PTPase), by iodoacetate and not by iodoacetamide suggested that iodoacetate interacts in a highly selective manner with the enzyme. The data indicate that iodoacetate binds at the active site of the enzyme with a stoichiometry of 0.8 mol of iodoacetate bound per mol of rat LAR. A single [14C]iodoacetate-labeled peptide was isolated following endoproteinase Lys-C digestion of the radiolabeled PTPase. Sequence analysis of the active site labeled peptide demonstrates that Cys-1522 contains the radiolabel. This residue has been shown by site-directed mutagenesis to be essential for rat LAR activity (Pot, D. A., Woodford, T. A., Remboutsika, E., Haun, R. S., and Dixon, J. E. (1991) J. Biol. Chem. 266, 19688-19696). Iodoacetate reacts only with the first domain of this double domain PTPase. These results, for the first time, directly identify the highly reactive cysteine residue at the active site of a PTPase and highlight the ability of this residue to participate as a nucleophile in the hydrolysis of phosphate from tyrosine. IS - 1 JF - Journal of Biological Chemistry EP - 143 TI - Active site labeling of a receptor-like protein tyrosine phosphatase. VL - 267 SP - 140 KW - classic KW - ptp AU - Pot, DA AU - Dixon, JE PY - 1992/01/05/ UR - http://www.jbc.org/content/267/1/140.abstract ER -