Pyruvate carboxylase catalyzes a 2-step reaction, involving the ATP-dependent carboxylation of the covalently attached biotin in the first step and the transfer of the carboxyl group to pyruvate in the second. Catalyzes in a tissue specific manner, the initial reactions of glucose (liver, kidney) and lipid (adipose tissue, liver, brain) synthesis from pyruvate. ATP + hydrogencarbonate + pyruvate = ADP + H(+) + oxaloacetate + phosphate Binds 1 Mn(2+) ion per subunit. Carbohydrate biosynthesis; gluconeogenesis. Homotetramer (PubMed:18297087). Interacts (via the biotin carboxylation domain) with SIRT4 (PubMed:23438705). Acetylation of Lys-748 might play a role in catalytic activity regulation. The disease is caused by variants affecting the gene represented in this entry. Pyruvate carboxylase entry