|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions → Protein-Modification Reactions|
|Reactions Classified By Substrate → Macromolecule Reactions → Protein-Reactions → Protein-Modification Reactions|
EC Number: 126.96.36.199
Enzymes and Genes:
lipoyl-protein ligase A : lplA ( Escherichia coli K-12 substr. MG1655 )
lipoate-protein ligase : lplJ ( Bacillus subtilis subtilis 168 )
lipoate-protein ligase A : lplA , lplB ( Thermoplasma acidophilum )
In Pathway: lipoate salvage I
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
Most BioCyc compounds have been protonated to a reference pH value of 7.3, and some reactions have been computationally balanced for hydrogen by adding free protons. Please see the PGDB Concepts Guide for more information.
Mass balance status: Balanced.
Enzyme Commission Primary Name: lipoate—protein ligase
Enzyme Commission Synonyms: LplA, lipoate protein ligase, lipoate-protein ligase A, LPL, LPL-B
Standard Gibbs Free Energy (ΔrG'° in kcal/mol): -85.63157 [Latendresse13]
Enzyme Commission Summary:
Requires Mg2+. Both 6S- and 6R-lipoates can act as substrates but there is a preference for the naturally occurring R-form. Selenolipoate, i.e. 5-(1,2-diselenolan-3-yl)pentanoic acid, and 6-sulfanyloctanoate can also act as substrates, but more slowly [Green95]. Responsible for lipoylation in the presence of exogenous lipoic acid. Lipoylation is essential for the function of several key enzymes involved in oxidative metabolism, including pyruvate dehydrogenase (E(2) domain), 2-oxoglutarate dehydrogenase (E(2) domain), the branched-chain 2-oxoacid dehydrogenases and the glycine cleavage system (H protein) [Jordan97b]. Attaches lipoic acid to the lipoyl domains of these proteins. It is likely that an alternative pathway, involving EC 188.8.131.52 and EC 184.108.40.206 is the normal route for lipoylation [Perham00].
Unification Links: KEGG:R07771
Fujiwara05: Fujiwara K, Toma S, Okamura-Ikeda K, Motokawa Y, Nakagawa A, Taniguchi H (2005). "Crystal structure of lipoate-protein ligase A from Escherichia coli. Determination of the lipoic acid-binding site." J Biol Chem 280(39);33645-51. PMID: 16043486
Jordan97b: Jordan SW, Cronan JE (1997). "A new metabolic link. The acyl carrier protein of lipid synthesis donates lipoic acid to the pyruvate dehydrogenase complex in Escherichia coli and mitochondria." J Biol Chem 272(29);17903-6. PMID: 9218413
Kim05d: Kim DJ, Kim KH, Lee HH, Lee SJ, Ha JY, Yoon HJ, Suh SW (2005). "Crystal structure of lipoate-protein ligase A bound with the activated intermediate: insights into interaction with lipoyl domains." J Biol Chem 280(45);38081-9. PMID: 16141198
Morris94: Morris TW, Reed KE, Cronan JE (1994). "Identification of the gene encoding lipoate-protein ligase A of Escherichia coli. Molecular cloning and characterization of the lplA gene and gene product." J Biol Chem 269(23);16091-100. PMID: 8206909
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