carboxy-lyase activity ribulose-bisphosphate carboxylase activity MetaCyc:RIBULOSE-BISPHOSPHATE-CARBOXYLASE-RXN RuBP carboxylase activity carboxydismutase activity D-ribulose-1,5-bisphosphate carboxylase activity ribulose 1,5-diphosphate carboxylase activity GO:0016984 D-ribulose 1,5-diphosphate carboxylase activity RuBisCO activity ribulose 1,5-diphosphate carboxylase/oxygenase activity EC:4.1.1.39 diphosphoribulose carboxylase activity ribulose diphosphate carboxylase activity RHEA:23124 ribulose diphosphate carboxylase/oxygenase activity ribulose bisphosphate carboxylase/oxygenase activity ribulose 1,5-bisphosphate carboxylase/oxygenase activity ribulose 1,5-bisphosphate carboxylase activity Catalysis of the reaction: 2 (2R)-3-phosphoglycerate + 2 H+ = CO2 + D-ribulose 1,5-bisphosphate + H2O. molecular_function