OXCT1 : 3-oxoacid CoA-transferase 1
Description
The OXCT1 (3-oxoacid CoA-transferase 1) is a protein-coding gene located on chromosome 5.
The OXCT1 gene provides instructions for making an enzyme called succinyl-CoA:3-ketoacid CoA transferase, often abbreviated as SCOT. The SCOT enzyme is made in the energy-producing centers of cells (mitochondria). The enzyme plays a role in the breakdown of ketones, which are molecules produced by the liver during the breakdown of fats. Ketones are an important source of energy during prolonged periods without food (fasting) or when energy demands are increased, such as during illness or when exercising. In the processing of ketones, the SCOT enzyme converts the molecule acetoacetate to acetoacetyl-CoA.
The OXCT1 gene encodes the enzyme succinyl-CoA:3-ketoacid CoA transferase (SCOT), a key player in ketone body catabolism. SCOT catalyzes the first and rate-limiting step of ketone body utilization in extrahepatic tissues. It transfers coenzyme A (CoA) from succinyl-CoA to acetoacetate, generating acetoacetyl-CoA. Acetoacetyl-CoA is further metabolized by acetoacetyl-CoA thiolase into two acetyl-CoA molecules, which then enter the citric acid cycle for energy production. SCOT exists as a dimer, with both subunits forming enzyme-CoA thiolester intermediates. However, only one subunit is capable of transferring the CoA moiety to the acceptor carboxylate (3-oxo acid) to produce a new acyl-CoA. The formation of the enzyme-CoA intermediate occurs through an unstable anhydride species formed between the carboxylate groups of the enzyme and substrate.
OXCT1 is also known as OXCT, SCOT.
