title: Retention of the oxygens at C-2 and C-3 of D-ribulose 1,5-bisphosphate in the reaction catalyzed by ribulose-1,5-bisphosphate carboxylase.
abstract: Ribulose-1,5-bisphosphate carboxylase catalyzes the conversion of D ribulose 1,5-bisphosphate and CO2 to 3-phospho-D-glycerate, with retention of the oxygen atoms at both C-2 and C-3 of the substrate. This observation is consistent with mechanistic pathways involving an enediol intermediate and eliminates suggested mechanisms that involve covalent intermediates between the enzyme and ribulose 1,5-bisphosphate in which the substrate oxygen at C-2 or C-3 is compulsorily lost.
mesh_terms: D002262:Carboxy-Lyases / Q000378:metabolism*; D007553:Isotope Labeling; D013058:Mass Spectrometry; D010103:Oxygen Isotopes; D010428:Pentosephosphates; D012247:Rhodospirillum rubrum / Q000201:enzymology; D012273:Ribulose-Bisphosphate Carboxylase / Q000378:metabolism*; D012274:Ribulosephosphates
chemical_list: D010103:Oxygen Isotopes; D010428:Pentosephosphates; D012274:Ribulosephosphates; C001933:ribulose-1,5 diphosphate; D002262:Carboxy-Lyases; D012273:Ribulose-Bisphosphate Carboxylase