title: Rapid and irreversible inhibition of creatine kinase by peroxynitrite.
abstract: We examined the ability of peroxynitrite and other .NO-derived oxidants to inhibit creatine kinase (CK). Peroxynitrite potently inhibited CK activity and depleted protein thiols. The rate constant for this reaction was 8.85x10(5) M(-1) s(-1). Glutathione did not reactivate CK activity nor did it regenerate protein thiol content. In contrast, glutathione reactivated CK, and regenerated protein thiols, after inhibition by either .NO or oxidized glutathione (GSSG). Peroxynitrite did not irreversibly inhibit CK after it had been treated with GSSG to block protein thiols. We conclude that thiol oxidation is a critical event leading to inactivation of CK by peroxynitrite.
authors.affiliation: Biophysics Research Institute, Medical College of Wisconsin, Milwaukee 53226-0509, USA.
authors.forename: E A
authors.initials: EA
authors.lastname: Konorev
authors.forename: N
authors.initials: N
authors.lastname: Hogg
authors.forename: B
authors.initials: B
authors.lastname: Kalyanaraman
mesh_terms: D000097:Acetonitriles / Q000494:pharmacology; D000818:Animals; D003402:Creatine Kinase / Q000037:antagonists & inhibitors*; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004793:Enzyme Reactivators / Q000494:pharmacology; D005978:Glutathione / Q000494:pharmacology; D019803:Glutathione Disulfide / Q000494:pharmacology; D007700:Kinetics; D008981:Molsidomine / Q000031:analogs & derivatives / Q000494:pharmacology; D009025:Morpholines / Q000494:pharmacology; D009566:Nitrates / Q000494:pharmacology*; D009569:Nitric Oxide / Q000502:physiology; D016877:Oxidants / Q000494:pharmacology*; D011817:Rabbits; D013438:Sulfhydryl Compounds / Q000032:analysis; D013481:Superoxides
chemical_list: D000097:Acetonitriles; D004791:Enzyme Inhibitors; D004793:Enzyme Reactivators; D009025:Morpholines; D009566:Nitrates; D016877:Oxidants; D013438:Sulfhydryl Compounds; D013481:Superoxides; C093946:SIN 1C; C039642:peroxynitric acid; D009569:Nitric Oxide; C002385:linsidomine; D008981:Molsidomine; D003402:Creatine Kinase; D005978:Glutathione; D019803:Glutathione Disulfide