KEGG   ENZYME: 1.4.1.27
Entry
EC 1.4.1.27                 Enzyme                                 

Name
glycine cleavage system;
GCV
Class
Oxidoreductases;
Acting on the CH-NH2 group of donors;
With NAD+ or NADP+ as acceptor
Sysname
glycine:NAD+ 2-oxidoreductase (tetrahydrofolate-methylene-adding)
Reaction(IUBMB)
glycine + tetrahydrofolate + NAD+ = 5,10-methylenetetrahydrofolate + NH3 + CO2 + NADH [RN:R01221]
Reaction(KEGG)
R01221
Substrate
glycine [CPD:C00037];
tetrahydrofolate [CPD:C00101];
NAD+ [CPD:C00003]
Product
5,10-methylenetetrahydrofolate [CPD:C00143];
NH3 [CPD:C00014];
CO2 [CPD:C00011];
NADH [CPD:C00004]
Comment
The glycine cleavage (GCV) system is a large multienzyme complex that belongs to the 2-oxoacid dehydrogenase complex family, which also includes EC 1.2.1.25, branched-chain alpha-keto acid dehydrogenase system, EC 1.2.1.105, 2-oxoglutarate dehydrogenase system, EC 1.2.1.104, pyruvate dehydrogenase system, and EC 2.3.1.190, acetoin dehydrogenase system. The GCV system catalyses the reversible oxidation of glycine, yielding carbon dioxide, ammonia, 5,10-methylenetetrahydrofolate and a reduced pyridine nucleotide. Tetrahydrofolate serves as a recipient for one-carbon units generated during glycine cleavage to form the methylene group. The GCV system consists of four protein components, the P protein (EC 1.4.4.2, glycine dehydrogenase (aminomethyl-transferring)), T protein (EC 2.1.2.10, aminomethyltransferase), L protein (EC 1.8.1.4, dihydrolipoyl dehydrogenase), and the non-enzyme H protein (lipoyl-carrier protein). The P protein catalyses the pyridoxal phosphate-dependent liberation of CO2 from glycine, leaving a methylamine moiety. The methylamine moiety is transferred to the lipoic acid group of the H protein, which is bound to the P protein prior to decarboxylation of glycine. The T protein catalyses the release of ammonia from the methylamine group and transfers the remaining C1 unit to tetrahydrofolate, forming 5,10-methylenetetrahydrofolate. The L protein then oxidizes the lipoic acid component of the H protein and transfers the electrons to NAD+, forming NADH.
History
EC 1.4.1.27 created 2020
Pathway
ec00630  Glyoxylate and dicarboxylate metabolism
Reference
1  [PMID:4460882]
  Authors
Motokawa Y, Kikuchi G.
  Title
Glycine metabolism by rat liver mitochondria. Reconstruction of the reversible glycine cleavage system with partially purified protein components.
  Journal
Arch Biochem Biophys 164:624-33 (1974)
DOI:10.1016/0003-9861(74)90074-5
Reference
2  [PMID:7440563]
  Authors
Hiraga K, Kikuchi G.
  Title
The mitochondrial glycine cleavage system. Functional association of glycine decarboxylase and aminomethyl carrier protein.
  Journal
J Biol Chem 255:11671-6 (1980)
Reference
3  [PMID:7053363]
  Authors
Okamura-Ikeda K, Fujiwara K, Motokawa Y.
  Title
Purification and characterization of chicken liver T-protein, a component of the glycine cleavage system.
  Journal
J Biol Chem 257:135-9 (1982)
Reference
4  [PMID:6469978]
  Authors
Fujiwara K, Okamura-Ikeda K, Motokawa Y.
  Title
Mechanism of the glycine cleavage reaction. Further characterization of the intermediate attached to H-protein and of the reaction catalyzed by T-protein.
  Journal
J Biol Chem 259:10664-8 (1984)
Reference
5  [PMID:8375392]
  Authors
Okamura-Ikeda K, Ohmura Y, Fujiwara K, Motokawa Y
  Title
Cloning and nucleotide sequence of the gcv operon encoding the Escherichia coli glycine-cleavage system.
  Journal
Eur J Biochem 216:539-48 (1993)
DOI:10.1111/j.1432-1033.1993.tb18172.x
Other DBs
ExplorEnz - The Enzyme Database: 1.4.1.27
IUBMB Enzyme Nomenclature: 1.4.1.27
ExPASy - ENZYME nomenclature database: 1.4.1.27
BRENDA, the Enzyme Database: 1.4.1.27

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