EC 2.3.1.168 - Dihydrolipoyllysine-residue (2-methylpropanoyl)transferase

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IntEnz Enzyme Nomenclature
EC 2.3.1.168

Names

Accepted name:
dihydrolipoyllysine-residue (2-methylpropanoyl)transferase
Other names:
dihydrolipoyl transacylase
enzyme-dihydrolipoyllysine:2-methylpropanoyl-CoA S-(2-methylpropanoyl)transferase
2-methylpropanoyl-CoA:enzyme-6-N-(dihydrolipoyl)lysine S-(2-methylpropanoyl)transferase
Systematic name:
2-methylpropanoyl-CoA:enzyme-N6-(dihydrolipoyl)lysine S-(2-methylpropanoyl)transferase

Reaction

Comments:

A multimer (24-mer) of this enzyme forms the core of the multienzyme 3-methyl-2-oxobutanoate dehydrogenase complex, and binds tightly both EC 1.2.4.4, 3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring) and EC 1.8.1.4, dihydrolipoyl dehydrogenase. The lipoyl group of this enzyme is reductively 2-methylpropanoylated by EC 1.2.4.4, and the only observed direction catalysed by EC 2.3.1.168 is that where this 2-methylpropanoyl is passed to coenzyme A. In addition to the 2-methylpropanoyl group, formed when EC 1.2.4.4 acts on the oxoacid that corresponds with valine, this enzyme also transfers the 3-methylbutanoyl and S-2-methylbutanoyl groups, donated to it when EC 1.2.4.4 acts on the oxo acids corresponding with leucine and isoleucine.

Links to other databases

Enzymes and pathways: NC-IUBMB , BRENDA , DIAGRAM , ExplorEnz , ENZYME@ExPASy , KEGG , MetaCyc , UniPathway
Structural data: CSA , EC2PDB
Gene Ontology: GO:0043754
UniProtKB/Swiss-Prot:

References

  1. Massey, L.K., Sokatch, J.R. and Conrad, R.S.
    Branched-chain amino acid catabolism in bacteria.
    Bacteriol. Rev. 40: 42-54 (1976). [PMID: 773366]
  2. Chuang, D.T., Hu, C.C., Ku, L.S., Niu, W.L., Myers, D.E. and Cox R.P.
    Catalytic and structural properties of the dihydrolipoyl transacylase component of bovine branched-chain α-keto acid dehydrogenase.
    J. Biol. Chem. 259: 9277-9284 (1984). [PMID: 6746648]
  3. Wynn, R.M., Davie, J.R., Zhi, W., Cox, R.P. and Chuang, D.T.
    In vitro reconstitution of the 24-meric E2 inner core of bovine mitochondrial branched-chain α-keto acid dehydrogenase complex: requirement for chaperonins GroEL and GroES.
    Biochemistry 33: 8962-8968 (1994). [PMID: 7913832]
  4. Perham, R.N.
    Swinging arms and swinging domains in multifunctional enzymes: catalytic machines for multistep reactions.
    Annu. Rev. Biochem. 69: 961-1004 (2000). [PMID: 10966480]

[EC 2.3.1.168 created 2003]