title: Dual activity of quinolinate synthase: triose phosphate isomerase and dehydration activities play together to form quinolinate.
abstract: Quinolinate synthase (NadA) is an Fe4S4 cluster-containing dehydrating enzyme involved in the synthesis of quinolinic acid (QA), the universal precursor of the essential coenzyme nicotinamide adenine dinucleotide. The reaction catalyzed by NadA is not well understood, and two mechanisms have been proposed in the literature that differ in the nature of the molecule (DHAP or G-3P) that condenses with iminoaspartate (IA) to form QA. In this article, using biochemical approaches, we demonstrate that DHAP is the triose that condenses with IA to form QA. The capacity of NadA to use G-3P is due to its previously unknown triose phosphate isomerase activity.
authors.affiliation: Université Grenoble Alpes , iRTSV-LCBM, F-38000 Grenoble, France.|CNRS , iRTSV-LCBM, F-38000 Grenoble, France.|CEA , iRTSV-LCBM-Biocat, F-38000 Grenoble, France.
authors.forename: Debora
authors.initials: D
authors.lastname: Reichmann
authors.affiliation: Université Grenoble Alpes , iRTSV-BGE, Grenoble 38000, France.|CEA , iRTSV-BGE, Grenoble 38000, France.|INSERM , BGE, Grenoble 38000, France.
authors.forename: Yohann
authors.initials: Y
authors.lastname: Couté
authors.affiliation: Université Grenoble Alpes , iRTSV-LCBM, F-38000 Grenoble, France.|CNRS , iRTSV-LCBM, F-38000 Grenoble, France.|CEA , iRTSV-LCBM-Biocat, F-38000 Grenoble, France.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Ollagnier de Choudens
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D004099:Dihydroxyacetone Phosphate / Q000378:metabolism; D053858:Metabolic Networks and Pathways; D008956:Models, Chemical; D009097:Multienzyme Complexes / Q000737:chemistry* / Q000378:metabolism*; D009243:NAD / Q000096:biosynthesis; D017378:Quinolinic Acid / Q000378:metabolism; D020124:Thermotoga maritima / Q000201:enzymology; D014305:Triose-Phosphate Isomerase / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D009097:Multienzyme Complexes; D009243:NAD; D001224:Aspartic Acid; C022512:quinolinic acid synthetase; D004099:Dihydroxyacetone Phosphate; C031948:iminoaspartic acid; D014305:Triose-Phosphate Isomerase; D017378:Quinolinic Acid