title: Synthesis and utility of 14C-labeled nicotinamide cofactors.
abstract: A new method for the synthesis of the reduced form of beta-nicotinamide [U-14C]adenine dinucleotide 2(')-phosphate([Ad-14C]NADPH) is presented. The present synthesis results in a radioactive material with a specific activity that is greater than 220 mCi/mmol. This method could easily be adapted for syntheses of 14C-labeled NADH, NADP(+), or any nicotinamide cofactors with radiolabels in other positions. Since these cofactors are so ubiquitous, the use and applications of such labeled material has broad implications. The utility of the labeled cofactor for determination of substrates for nicotinamide-dependent enzymes in the nano- to femtomole scale, in alternative enzymatic assays, and in kinetic isotope effect studies is discussed.
authors.affiliation: Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA.
authors.forename: Kelli A
authors.initials: KA
authors.lastname: Markham
authors.forename: R Steven
authors.initials: RS
authors.lastname: Sikorski
authors.forename: Amnon
authors.initials: A
authors.lastname: Kohen
mesh_terms: D000244:Adenosine Diphosphate / Q000737:chemistry; D000255:Adenosine Triphosphate / Q000737:chemistry; D002247:Carbon Isotopes / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D003404:Creatinine / Q000737:chemistry; D007553:Isotope Labeling / Q000379:methods*; D009243:NAD / Q000737:chemistry*; D009249:NADP / Q000138:chemical synthesis*; D009536:Niacinamide / Q000138:chemical synthesis*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000737:chemistry
chemical_list: D002247:Carbon Isotopes; D009243:NAD; D009536:Niacinamide; D009249:NADP; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D003404:Creatinine; D017853:Phosphotransferases (Alcohol Group Acceptor); C021844:NAD kinase