Pyruvate carboxylase (PC) is a mitochondrial enzyme that catalyzes the ATP-dependent carboxylation of biotin followed by carboxyl group transfer to pyruvate, functioning as a critical anaplerotic enzyme. The enzyme operates in a tissue-specific manner, initiating glucose synthesis in liver and kidney, and lipid synthesis in adipose tissue, liver, and brain. PC catalyzes the first committed step of gluconeogenesis and lipogenesis pathways, linking pyruvate metabolism to biosynthetic processes. Deficiency of PC results in pyruvate carboxylase deficiency, a rare genetic disorder affecting metabolic homeostasis. The enzyme's biotin-dependent mechanism and its role in maintaining cytosolic and mitochondrial NAD(P)+ pools underscore its fundamental importance in cellular energy metabolism and anabolic biosynthesis. Although the provided abstracts do not contain specific mechanistic or clinical data on PC function and disease, the disorder represents a significant metabolic complication when enzymatic activity is impaired, affecting glucose and lipid homeostasis across multiple tissues.