BIOLOGICAL SIGNIFICANCE OF PYRUVATE CARBOXYLASE IN METABOLISM AND ITS ROLE IN METABOLIC PROCESSES
DOI:
https://doi.org/10.5281/Keywords:
pyruvate carboxylase, lactic acidosis, oxaloacetate, biotin, ATP, anaplerosis, gluconeogenesis, tricarboxylic acid cycle, acetyl-CoA, carbohydrate metabolism, metabolism.Abstract
Pyruvate carboxylase (EC 6.4.1.1) belongs to the group of biotin-dependent carboxylase enzymes and catalyzes the carboxylation of pyruvate to oxaloacetate. The reaction catalyzed by this enzyme plays an important role in several key processes of cellular metabolism, particularly in the anaplerotic replenishment of the tricarboxylic acid cycle and in gluconeogenesis. This article analyzes the biochemical characteristics and catalytic mechanism of pyruvate carboxylase, its biological significance in metabolism, and its functional role in major metabolic processes based on the scientific literature. The literature review demonstrated that oxaloacetate produced through the activity of pyruvate carboxylase contributes to replenishing the pool of intermediate metabolites of the tricarboxylic acid cycle, supporting gluconeogenesis, and maintaining the interconnection between various metabolic pathways. Allosteric regulation of enzyme activity by acetyl-CoA is of particular importance in regulating the metabolic fate of pyruvate according to the functional state of the cell. Impaired pyruvate carboxylase activity may lead to the development of inherited metabolic disorders characterized by lactic acidosis, disturbances in metabolic homeostasis, and neurological abnormalities. The findings characterize pyruvate carboxylase as one of the key enzymes of central metabolism.
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