CATH Classification

Domain Context

CATH Clusters

Superfamily 3.40.50.920
Functional Family

Enzyme Information

1.2.4.4
3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring).
based on mapping to UniProt P21953
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] lipoyllysine = [dihydrolipoyllysine- residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO(2).
-!- It acts not only on 3-methyl-2-oxobutanaoate, but also on 4-methyl-2- oxopentanoate and (S)-3-methyl-2-oxopentanoate, so that it acts on the 2-oxo acids that derive from the action of transaminases on valine, leucine and isoleucine. -!- It is a component of the multienzyme 3-methyl-2-oxobutanoate dehydrogenase complex in which multiple copies of it are bound to a core of molecules of EC 2.3.1.168, which also binds multiple copies of EC 1.8.1.4. -!- It does not act on free lipoamide or lipoyllysine, but only on the lipoyllysine residue in EC 2.3.1.168. -!- Formerly EC 1.2.4.3.

UniProtKB Entries (1)

P21953
ODBB_HUMAN
Homo sapiens
2-oxoisovalerate dehydrogenase subunit beta, mitochondrial

PDB Structure

PDB 1U5B
External Links
Method X-RAY DIFFRACTION
Organism Escherichia
Primary Citation
Molecular mechanism for regulation of the human mitochondrial branched-chain alpha-ketoacid dehydrogenase complex by phosphorylation
Wynn, R.M., Kato, M., Machius, M., Chuang, J.L., Li, J., Tomchick, D.R., Chuang, D.T.
Structure