title: Glutathionylation of the alpha-subunit of Na,K-ATPase from rat heart by oxidized glutathione inhibits the enzyme.
abstract: A partially purified Na,K-ATPase preparation from rat heart containing α1- and α2-isoforms of the enzyme was shown to include both subunits in S-glutathionylated state. Glutathionylation of the α1-subunit (but not of the α2-subunit) was partially removed when the preparation was isolated in the presence of dithiothreitol. The addition of oxidized glutathione irreversibly inhibited both isoforms. Inhibition of the enzyme containing the α1-subunit was biphasic, and the rate constants of the inhibition were 3745 ± 360 and 246 ± 18 M(-1)·min(-1). ATP, ADP, and AMP protected the Na,K-ATPase against inactivation by oxidized glutathione.
authors.affiliation: Lomonosov Moscow State University, Department of Biochemistry, Biological Faculty, Moscow, 119991, Russia. od_lopina@mail.ru.
authors.forename: Meng
authors.initials: M
authors.lastname: Xianyu
authors.forename: I Yu
authors.initials: IY
authors.lastname: Petrushanko
authors.forename: E A
authors.initials: EA
authors.lastname: Klimanova
authors.forename: E A
authors.initials: EA
authors.lastname: Dergousova
authors.forename: O D
authors.initials: OD
authors.lastname: Lopina
mesh_terms: D000818:Animals; D004791:Enzyme Inhibitors / Q000378:metabolism / Q000494:pharmacology; D019803:Glutathione Disulfide / Q000378:metabolism* / Q000494:pharmacology*; D009206:Myocardium / Q000201:enzymology*; D011499:Protein Processing, Post-Translational / Q000187:drug effects*; D021122:Protein Subunits / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D000254:Sodium-Potassium-Exchanging ATPase / Q000737:chemistry*
chemical_list: D004791:Enzyme Inhibitors; D021122:Protein Subunits; D000254:Sodium-Potassium-Exchanging ATPase; D019803:Glutathione Disulfide