[Modification of arginine residues in pyruvate kinase (author's transl)].
Pyruvate kinase from pig heart is inactivated by the specific arginyl reagent phenylglyoxal. The loss of activity is caused by the reaction of a single molecule of phenylglyoxal per subunit of enzyme. During inactivation 3 - 6 arginyl residues are modified dependent on the concentration of phenylglyoxal used for modification. The solubility of the protein is reduced by the modification. ATP or phosphoenolpyruvate protect against inactivation. A single arginine is less subject to chemical modification in their presence. Therefore we assume that an arginine is essential at the substrate binding site. The activating ion K does not affectinactivation, where as Mg2 diminishes inactivation. Pyruvate kinase from rabbit muscle is modified by phenylglyoxal in a similar manner.
D000818:Animals; D001120:Arginine; D001665:Binding Sites; D006037:Glyoxal / Q000031:analogs & derivatives / Q000494:pharmacology; D007700:Kinetics; D008970:Molecular Weight; D009206:Myocardium / Q000201:enzymology; D011770:Pyruvate Kinase / Q000378:metabolism; D013552:Swine
D006037:Glyoxal; D001120:Arginine; D011770:Pyruvate Kinase
Modifizierung von Argininresten in Pyruvat-Kinase.