title: Activity of nucleoside diphosphate kinase α (NDPK α) capable of binding to outer mitochondrial membrane accounts for less than 10% of total NDPK activity present in cytoplasm of liver cells.
abstract: During incubation of a constant volume of rat liver cytosol with an increasing quantity of mitochondrial protein in the presence of 3.3 mM MgCl(2), the binding of nucleoside diphosphate kinase (NDPK) from the cytosol to mitochondrial membranes is described by a saturation curve. The highest bound NDPK activity accounts for less than 9% of the added activity. Analysis of the results suggests that only one NDPK isozyme is bound to the membranes. Western blotting showed it to be NDPK α, a homolog of human NDPK-B. Substrates of NDPK, hexokinase, and glycerol kinase, as well as N,N'-dicyclohexylcarbodiimide and palmitate, did not influence the association of NDPK with mitochondrial membranes. We conclude that the sites of NDPK binding to the outer mitochondrial membrane are not identical to those of hexokinase and glycerol kinase.
authors: Department of Biochemistry, Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia. tlipskaya@yandex.ru
authors: T Yu
authors: TY
authors: Lipskaya
authors: V V
authors: VV
authors: Voinova
mesh_terms: D000818:Animals; D015153:Blotting, Western; D003600:Cytosol / Q000201:enzymology; D005991:Glycerol Kinase / Q000378:metabolism; D022781:Hepatocytes / Q000201:enzymology*; D006593:Hexokinase / Q000378:metabolism; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism; D008099:Liver / Q000166:cytology / Q000201:enzymology; D008930:Mitochondria, Liver / Q000201:enzymology*; D051336:Mitochondrial Membranes / Q000201:enzymology*; D009701:Nucleoside-Diphosphate Kinase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D009994:Osmolar Concentration; D010766:Phosphorylation; D051381:Rats; D017386:Sequence Homology, Amino Acid
chemical_list: D007527:Isoenzymes; D006593:Hexokinase; D005991:Glycerol Kinase; D009701:Nucleoside-Diphosphate Kinase; C542596:NDPK-B protein, human; C576766:nucleoside diphosphate kinase, rat