Pyruvate carboxylase (PC) encoded by the gene PC is an enzyme of the ligase class that catalyzes (depending on the species) the physiologically irreversible carboxylation of pyruvate to form oxaloacetate (OAA).
The reaction it catalyzes is:
pyruvate + HCO−3 + ATP → oxaloacetate + ADP + PIt is an important anaplerotic reaction that creates oxaloacetate from pyruvate. [Source: Wikipedia 
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