Hydroxymethylglutaryl-CoA synthase, cytoplasmic; This enzyme condenses acetyl-CoA with acetoacetyl-CoA to form HMG-CoA, which is the substrate for HMG-CoA reductase.

Methylglutaconyl-CoA hydratase, mitochondrial; Catalyzes the conversion of 3-methylglutaconyl-CoA to 3- hydroxy-3-methylglutaryl-CoA. Also has itaconyl-CoA hydratase activity by converting itaconyl-CoA into citramalyl-CoA in the C5-dicarboxylate catabolism pathway. The C5-dicarboxylate catabolism pathway is required to detoxify itaconate, a vitamin B12-poisoning metabolite. Has very low enoyl-CoA hydratase activity. Was originally identified as RNA-binding protein that binds in vitro to clustered 5'-AUUUA-3' motifs.

Succinyl-CoA:3-ketoacid coenzyme A transferase 2, mitochondrial; Key enzyme for ketone body catabolism. Transfers the CoA moiety from succinate to acetoacetate. Formation of the enzyme-CoA intermediate proceeds via an unstable anhydride species formed between the carboxylate groups of the enzyme and substrate (By similarity). Belongs to the 3-oxoacid CoA-transferase family.

Succinyl-CoA:3-ketoacid coenzyme A transferase 1, mitochondrial; Key enzyme for ketone body catabolism. Transfers the CoA moiety from succinate to acetoacetate. Formation of the enzyme-CoA intermediate proceeds via an unstable anhydride species formed between the carboxylate groups of the enzyme and substrate; Belongs to the 3-oxoacid CoA-transferase family.

Acetyl-CoA acetyltransferase, mitochondrial; This is one of the enzymes that catalyzes the last step of the mitochondrial beta-oxidation pathway, an aerobic process breaking down fatty acids into acetyl-CoA. Using free coenzyme A/CoA, catalyzes the thiolytic cleavage of medium- to long-chain 3-oxoacyl-CoAs into acetyl-CoA and a fatty acyl-CoA shortened by two carbon atoms. The activity of the enzyme is reversible and it can also catalyze the condensation of two acetyl-CoA molecules into acetoacetyl-CoA. Thereby, it plays a major role in ketone body metabolism.

Acetyl-CoA acetyltransferase, cytosolic; Involved in the biosynthetic pathway of cholesterol.

Trifunctional enzyme subunit beta, mitochondrial; Mitochondrial trifunctional enzyme catalyzes the last three of the four reactions of the mitochondrial beta-oxidation pathway. The mitochondrial beta-oxidation pathway is the major energy-producing process in tissues and is performed through four consecutive reactions breaking down fatty acids into acetyl-CoA. Among the enzymes involved in this pathway, the trifunctional enzyme exhibits specificity for long- chain fatty acids. Mitochondrial trifunctional enzyme is a heterotetrameric complex composed of two proteins, the trifunctional en [...]

3-ketoacyl-CoA thiolase, peroxisomal; acetyl-CoA acyltransferase 1; Belongs to the thiolase-like superfamily. Thiolase family.

D-beta-hydroxybutyrate dehydrogenase, mitochondrial; 3-hydroxybutyrate dehydrogenase 1; Belongs to the short-chain dehydrogenases/reductases (SDR) family.