Phosphoenolpyruvate carboxykinase (ATP)

Phosphoenolpyruvate carboxykinase (ATP), often abbreviated as PEPCK (ATP), is an enzyme belonging to the lyase family. Its systematic name is ATP:oxaloacetate carboxy-lyase (transphosphorylating). As its name suggests, PEPCK (ATP) catalyzes the reversible decarboxylation of oxaloacetate (OAA) to phosphoenolpyruvate (PEP), using ATP as a phosphate donor. The reaction also produces ADP and carbon dioxide.

The overall reaction catalyzed by PEPCK (ATP) is:

Oxaloacetate + ATP ⇌ Phosphoenolpyruvate + ADP + CO₂

PEPCK (ATP) is primarily found in bacteria and other prokaryotes. Unlike the more common PEPCK (GTP) found in eukaryotes, PEPCK (ATP) utilizes ATP instead of GTP as the phosphoryl donor. Its role is significant in metabolic pathways such as gluconeogenesis, where it facilitates the production of glucose from non-carbohydrate precursors. It is also involved in various other metabolic processes, depending on the organism and its specific metabolic needs.

The enzyme's activity is tightly regulated to coordinate with other metabolic pathways and maintain cellular energy balance. Regulation can occur through a variety of mechanisms, including allosteric control, transcriptional regulation of gene expression, and post-translational modifications.

Due to its specific function and distribution primarily in prokaryotes, PEPCK (ATP) is a target for research related to bacterial metabolism and potential drug targets. Further studies may explore its detailed mechanism and regulatory processes, providing insights into bacterial physiology and potential biotechnological applications.