glycine cleavage complex

GO:0005960 · Other · Multiprotein complex · Proposed

A glycine-cleavage multienzyme protein complex that reversibly oxidizes glycine through L-, P-, H-, and T-protein components. [GO:0005960]

Synonyms: glycine cleavage system; glycine decarboxylase complex; glycine dehydrogenase (decarboxylating) complex; glycine synthase complex

UniProt location names: UniProt Consortium, CC BY 4.0. Reference label and route sources.

Components

Component	Type	Part of / acts on	Grounding	Genes	Essential	Role
Glycine dehydrogenase (decarboxylating)	Protein	part of	`InterPro:IPR020581`	gcvP	UNKNOWN	P-protein pyridoxal-phosphate enzyme that decarboxylates glycine and transfers the remaining aminomethyl group to lipoylated H protein. `GO:0005960` GO:0005960 defines the E. coli glycine cleavage complex as containing glycine dehydrogenase, also known as P-protein. `InterPro:IPR020581` InterPro IPR020581 is the exact glycine cleavage system P-protein family entry. `PMID:8375392` Okamura-Ikeda et al. 1993 identified E. coli gcvP as the structural gene encoding P-protein.
Glycine cleavage system H protein	Protein	part of	`InterPro:IPR017453`	gcvH	UNKNOWN	Lipoyl carrier protein that accepts aminomethyl groups from P-protein and presents them to T-protein. `GO:0005960` GO:0005960 defines the E. coli glycine cleavage complex as containing lipoyl-GcvH-protein. `InterPro:IPR017453` InterPro IPR017453 is the exact glycine cleavage system H-protein subgroup family entry. `PMID:8375392` Okamura-Ikeda et al. 1993 identified E. coli gcvH as the structural gene encoding H-protein.
Aminomethyltransferase	Protein	part of	`InterPro:IPR006223`	gcvT	UNKNOWN	T-protein folate-dependent aminomethyltransferase that transfers the aminomethyl group from H protein to tetrahydrofolate. `GO:0005960` GO:0005960 defines the E. coli glycine cleavage complex as containing aminomethyltransferase, also known as T-protein. `InterPro:IPR006223` InterPro IPR006223 is the exact glycine cleavage system T-protein family entry. `PMID:8375392` Okamura-Ikeda et al. 1993 identified E. coli gcvT as the structural gene encoding T-protein.
Dihydrolipoyl dehydrogenase	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	lpdA, lpd	UNKNOWN	L-protein dihydrolipoyl dehydrogenase that reoxidizes the reduced H-protein lipoyl arm. `GO:0005960` GO:0005960 defines the E. coli glycine cleavage complex as containing dihydrolipoamide dehydrogenase, also known as L-protein. `UniProtKB:P0A9P0` UniProtKB P0A9P0 identifies E. coli LpdA/Lpd as the glycine cleavage system L protein.

Organism-specific protein examples

Named proteins in which each component's role was established, with the organism the evidence comes from. The component above is the taxon-agnostic family; these are the specific entries behind it.

Glycine dehydrogenase (decarboxylating)

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P33195`	Glycine dehydrogenase (decarboxylating)	gcvP	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (2 references) Reviewed E. coli K-12 gcvP accession for glycine cleavage P-protein. `UniProtKB:P33195` UniProtKB P33195 is the reviewed E. coli K-12 entry for glycine cleavage system P-protein. `PMID:8375392` Okamura-Ikeda et al. 1993 sequenced the E. coli gcvT-gcvH-gcvP operon encoding the T, H and P proteins.

Glycine cleavage system H protein

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P0A6T9`	Glycine cleavage system H protein	gcvH	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (2 references) Reviewed E. coli K-12 gcvH accession for glycine cleavage H-protein. `UniProtKB:P0A6T9` UniProtKB P0A6T9 is the reviewed E. coli K-12 entry for glycine cleavage system H-protein. `PMID:8375392` Okamura-Ikeda et al. 1993 sequenced gcvH in the E. coli gcv operon.

Aminomethyltransferase

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P27248`	Aminomethyltransferase	gcvT	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (2 references) Reviewed E. coli K-12 gcvT accession for glycine cleavage T-protein. `UniProtKB:P27248` UniProtKB P27248 is the reviewed E. coli K-12 entry for glycine cleavage system T-protein. `PMID:8375392` Okamura-Ikeda et al. 1993 sequenced gcvT in the E. coli gcv operon.

Dihydrolipoyl dehydrogenase

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P0A9P0`	Dihydrolipoyl dehydrogenase	lpdA	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (2 references) Reviewed E. coli K-12 lpdA/lpd accession for the shared glycine cleavage L-protein. `UniProtKB:P0A9P0` UniProtKB P0A9P0 is the reviewed E. coli K-12 entry for dihydrolipoyl dehydrogenase. `GO:0005960` GO:0005960 names dihydrolipoamide dehydrogenase as the E. coli glycine cleavage complex L protein.

Canonical examples

NCBITaxon:83333 Escherichia coli K-12 — Bacterial source of the cloned gcv operon sequence for the T, H and P proteins and of the reviewed UniProtKB examples. [PMID:8375392]

Functions

glycine dehydrogenase (decarboxylating) activity GO:0004375 — The P-protein constituent decarboxylates glycine and transfers the remaining aminomethyl group to the H-protein lipoyl arm during glycine cleavage.
- GO:0005960 QuickGO links the glycine cleavage complex to glycine dehydrogenase (decarboxylating) activity.
- GO:0004375 GO:0004375 is the molecular-function term for glycine cleavage P-protein activity.
- InterPro:IPR020581 InterPro IPR020581 carries GO:0004375 for glycine cleavage system P proteins.

Discussions

CURATION_TODO (OPEN): Can the glycine cleavage L-protein be grounded to an exact source-neutral family? The E. coli L protein is LpdA/Lpd, a dihydrolipoyl dehydrogenase shared by multiple multienzyme complexes. Keep the component reviewed-label-only until an exact L-protein family or glycine cleavage subcomplex grounding is verified.

Evidence

GO:0005960 Gene Ontology cellular-component term for the glycine cleavage complex and its exact synonymy.
GO:1990204 OLS4 reports GO:0005960 as an is-a child of GO:1990204 oxidoreductase complex.
GO:1990234 OLS4 reports GO:0005960 as an is-a child of GO:1990234 transferase complex.
GO:0004375 Gene Ontology molecular-function term for glycine dehydrogenase (decarboxylating) activity.
InterPro:IPR020581 InterPro family entry for glycine cleavage P proteins.
InterPro:IPR017453 InterPro family entry for glycine cleavage H proteins.
InterPro:IPR006223 InterPro family entry for glycine cleavage T proteins.
UniProtKB:P33195 Reviewed UniProtKB E. coli K-12 GcvP entry.
UniProtKB:P0A6T9 Reviewed UniProtKB E. coli K-12 GcvH entry.
UniProtKB:P27248 Reviewed UniProtKB E. coli K-12 GcvT entry.
UniProtKB:P0A9P0 Reviewed UniProtKB E. coli K-12 LpdA/Lpd entry.
PMID:8375392 PubMed identifier for Okamura-Ikeda et al. 1993, the European Journal of Biochemistry E. coli gcv operon sequence paper.
DOI:10.1111/j.1432-1033.1993.tb18172.x DOI for Okamura-Ikeda et al. 1993, as reported by PubMed.
PMID:3023185 PubMed identifier for Stauffer, Plamann and Stauffer 1986, the Gene E. coli glycine-cleavage enzyme system cloning paper.
DOI:10.1016/0378-1119(86)90185-X DOI for Stauffer, Plamann and Stauffer 1986, as reported by PubMed.

Curation history

2026-10-02T03:09:52Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-10-02T03:11:41Z codex · EXPANDED_RECORD — Added GO exact synonymy, oxidoreductase- and transferase-complex parentage, exact InterPro-grounded P/H/T constituents, a reviewed-label-only L constituent with a grounding TODO, reviewed E. coli K-12 UniProt examples, glycine dehydrogenase activity, and DOI/PMID evidence.

Source: data/structures/other/glycine_cleavage_complex.yaml