BCKDH synthesizes BCAA-CoA from KIC, KMVA, KIV

Xu J, Jakher Y, Ahrens-Nicklas RC. Brain Branched-Chain Amino Acids in Maple Syrup Urine Disease: Implications for Neurological Disorders. Int J Mol Sci. 2020 Oct 11;21(20). PMID: 33050626; PMCID: PMC7590055.; Brautigam CA, Chuang JL, Tomchick DR, Machius M, Chuang DT. Crystal structure of human dihydrolipoamide dehydrogenase: NAD+/NADH binding and the structural basis of disease-causing mutations. J Mol Biol. 2005 Jul 15;350(3):543–52. doi: 10.1016/j.jmb.2005.05.014. PMID: 15946682.; Chang CF, Chou HT, Chuang JL, Chuang DT, Huang TH. Solution structure and dynamics of the lipoic acid-bearing domain of human mitochondrial branched-chain alpha-keto acid dehydrogenase complex. J Biol Chem. 2002 May 03;277(18):15865–73. doi: 10.1074/jbc.m110952200. PMID: 11839747.; AEvarsson A, Chuang JL, Wynn RM, Turley S, Chuang DT, Hol WG. Crystal structure of human branched-chain alpha-ketoacid dehydrogenase and the molecular basis of multienzyme complex deficiency in maple syrup urine disease. Structure. 2000 Mar 15;8(3):277–91. doi: 10.1016/s0969-2126(00)00105-2. PMID: 10745006.; WYNN R, KOCHI H, COX R, CHUANG D. Differential processing of human and rat E1 a precursors of the branched-chain a-keto acid dehydrogenase complex caused by an N-terminal proline in the rat sequence. Biochimica et Biophysica Acta (BBA) - General Subjects. 1994 Sep 28;1201(1):125–8. doi: 10.1016/0304-4165(94)90161-9.; Reed LJ, Hackert ML. Structure-function relationships in dihydrolipoamide acyltransferases. Journal of Biological Chemistry. 1990 Jun;265(16):8971–4. doi: 10.1016/s0021-9258(19)38795-2.

Metabolites

CO2

Formula: CO2 (43.98983)

CAS ID: 124-38-9

H+

Formula: H (1.0078246)

CAS ID: 12408-02-5

Potassium cation

Formula: K (38.963708)

CAS ID: 24203-36-9

NAD(1-)

Formula: C21H26N7O14P2 (662.1012936000001)

CAS ID: 53-84-9



Enzyme

EC Number name full name note
1.2.4.4 3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring) 3-methyl-2-oxobutanoate:[dihydrolipoyllysine-residue (2-methylpropanoyl)transferase]-lipoyllysine 2-oxidoreductase (decarboxylating, acceptor-2-methylpropanoylating)
1.8.1.4 dihydrolipoyl dehydrogenase protein-N6-(dihydrolipoyl)lysine:NAD+ oxidoreductase
2.3.1.168 dihydrolipoyllysine-residue (2-methylpropanoyl)transferase 2-methylpropanoyl-CoA:enzyme-N6-(dihydrolipoyl)lysine S-(2-methylpropanoyl)transferase


Proteins

Protein ID name full name