title: Synthesis of spin-labeled photoaffinity derivatives of NAD+ and their interaction with lactate dehydrogenase.
abstract: The synthesis of NAD+ derivatives spin-labeled at either N6 or C8 of the adenine ring is described, in which the carboxamide function of the nicotinamide moiety is replaced by a diazirine ring. Irradiation of these compounds at 350 nm generates a carbene which will react with any functional group in its vicinity including hydrocarbons. Both NAD+ derivatives form tight ternary complexes with lactate dehydrogenase and were covalently incorporated into this enzyme. They may be employed for ESR studies when non-covalent interactions are too weak for motionally restricted species to be observed.
mesh_terms: D000818:Animals; D004578:Electron Spin Resonance Spectroscopy; D007202:Indicators and Reagents; D007770:L-Lactate Dehydrogenase / Q000378:metabolism*; D009206:Myocardium / Q000201:enzymology; D009243:NAD / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology; D013113:Spin Labels / Q000138:chemical synthesis* / Q000494:pharmacology; D013329:Structure-Activity Relationship; D013552:Swine
chemical_list: D007202:Indicators and Reagents; D013113:Spin Labels; D009243:NAD; D007770:L-Lactate Dehydrogenase