title: [Interaction of a membrane preparation of Na+, K+-ATPase with a spin-labeled analog of ATP].
abstract: Interaction of membrane Na+, K+-ATPase preparation from brain gray matter with spin-labelled ATP analogue, in which free iminoxyl radical is joined as a result of 2'(3')-OH ribose groups acylation, is studied. The rotatory mobility of spin-labelled ATP analogue in Na+,K+-ATPase preparation is found to change in non-linear manner during temperature variation (the break-point on the curve being at 20-23degrees C). It correlates with temperature dependence of Na+,K+-ATPase and temperature dependence of lipid viscosity in the membranes, determined by means of hydrophobic spin probes. Substitution of Mg2+ ions with paramagnetic Mn2+ ions resulted in an intense magnetic dipole-dipole interaction between a spin label and Mn2+ ion, which indicated the formation of triple complex enzyme--spin-labelled ATP--Mn2+.
mesh_terms: D000251:Adenosine Triphosphatases; D000255:Adenosine Triphosphate / Q000031:analogs & derivatives*; D000818:Animals; D001921:Brain / Q000201:enzymology; D002384:Catalysis; D002417:Cattle; D055598:Chemical Phenomena; D002621:Chemistry; D008345:Manganese; D008566:Membranes / Q000201:enzymology; D013113:Spin Labels; D013696:Temperature
chemical_list: D013113:Spin Labels; D008345:Manganese; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases
vernacular_title: Vzaimodeĭstvie membrannogo preparata Na+, K+-ATPazy so spin-mechenym analogom ATP