Any enzyme that catalyses the transfer or incorporation of carbon dioxide into a substrate molecule. Car-boxylation reactions usually require energy in the form of ATP or a related compound; a coenzyme, usually biotin, is also a part of most carboxylases. An example is pyruvate carboxylase, which catalyses the formation of oxaloacetate from pyruvic acid. As with many carboxylases, this is an allosteric enzyme, its activity being increased by the binding of acetyl CoA. See also ribulose bisphosphate carboxylase, phosphoenolpyruvate carboxylase. |
