Alpha-ketoacid dehydrogenase complex (AKDC)

Alpha-ketoacid dehydrogenase complexes are a family of large, mitochondrial multi-enzyme assemblies that catalyze the oxidative decarboxylation of alpha-ketoacids into their corresponding acyl-CoA derivatives (Reed, 2001, PubMed). This family includes three primary members: the pyruvate dehydrogenase complex (PDC), the alpha-ketoglutarate dehydrogenase complex (KGDHC), and the branched-chain alpha-keto acid dehydrogenase complex (BCKDC) (StatPearls, 2023). Each complex consists of three core enzymes (E1, E2, and E3), where the E1 subunit specifically requires thiamine pyrophosphate (TPP) as a critical cofactor to initiate the decarboxylation step (UniProt, 2024). These enzymes serve as metabolic gatekeepers, linking glycolysis and amino acid metabolism to the Citric Acid Cycle and ATP production. Genetic mutations in these complexes lead to severe metabolic disorders like maple syrup urine disease and lactic acidosis, while their downregulation is observed in neurodegenerative diseases such as Alzheimer's (NIH, 2023). In cancer therapy, these complexes are targeted by drugs like devimistat to exploit the metabolic vulnerabilities of malignant cells, effectively inhibiting mitochondrial energy production (PubChem, 2024). Therapeutic interventions often focus on restoring activity through thiamine supplementation or inhibiting regulatory kinases that normally suppress these enzymes (ClinicalTrials.gov, 2024).

Other names

2-oxoacid dehydrogenase complex2-OADCAlpha-ketoacid dehydrogenases – via thiamine pyrophosphateTPP-dependent alpha-ketoacid dehydrogenaseAlpha-keto acid dehydrogenase

Drugs targeting these complexes typically act through cofactor supplementation to restore enzymatic activity, or by modulating regulatory proteins such as pyruvate dehydrogenase kinases (PDKs) to maintain the complex in its active, dephosphorylated state. In oncology, certain inhibitors directly target the lipoate-binding sites of the E2 subunit or the E1 catalytic site to disrupt mitochondrial metabolism in cancer cells.