gamma-glutamyltransferase activity

traitmech:000160 · CLASS · PROPOSED

A physiological enzyme-activity phenotype in which a cell exhibits gamma-glutamyltransferase/glutathione-hydrolase activity, processing glutathione, glutathione-S-conjugates, or other N-terminal L-gamma-glutamyl substrates through a gamma-glutamyl-enzyme intermediate.

Trait evidence (3)

https://iubmb.qmul.ac.uk/enzyme/EC3/4/19/13.html
The enzyme binds its substrate by forming an initial γ-glutamyl-enzyme intermediate, releasing the L-cysteinylglycine part of the molecule. The enzyme then reacts with either a water molecule or a different acceptor substrate (usually an L-amino acid or a dipeptide) to form L-glutamate or a product containing a new γ-glutamyl isopeptide bond, respectively. The enzyme acts on glutathione, glutathione-S-conjugates, and, at a lower level, on other substrates with an N-terminal L-γ-glutamyl residue.

The NC-IUBMB EC 3.4.19.13 entry scopes the bifunctional glutathione gamma-glutamate hydrolase/gamma-glutamyltransferase enzyme across water- and acceptor-mediated reactions.
DOI:10.3389/fgene.2023.1240581
Like Helicobacter canis, these two putative isolates are positive for oxidase, gamma-glutamyl transferase, and alkaline phosphatase and negative for catalase and urease activities.

Wang et al. detected gamma-glutamyltransferase activity in two Helicobacter zhangjianzhongii isolates with the API Campy biochemical panel.
DOI:10.3389/fgene.2023.1240581
Both of these strains exhibit positive results for oxidase, gamma-glutamyl transferase, alkaline phosphatase, pyrrolidonyl arylamidase, L-arginine arylamidase, and L-aspartate arylamidase

The formal species description reports the same gamma-glutamyltransferase-positive phenotype in both H. zhangjianzhongii strains.

Provenance

Identifier source: TraitMech local identifier
Definition source: https://iubmb.qmul.ac.uk/enzyme/EC3/4/19/13.html

Parent traits (1)

phenotype METPO:1000059

Synonyms (3)

gamma-glutamyl transferase RELATED_SYNONYM · DOI:10.3389/fgene.2023.1240581
gamma-glutamyl transpeptidase RELATED_SYNONYM · https://iubmb.qmul.ac.uk/enzyme/EC3/4/19/13.html
glutathione gamma-glutamate hydrolase RELATED_SYNONYM · https://iubmb.qmul.ac.uk/enzyme/EC3/4/19/13.html

kg-microbe context

No kg-microbe node embedding matched this record in the 2026-04-25 deepwalk.

Canonical examples (1)

Organisms cited as exemplars of this trait. Taxon ids are NCBITaxon and link out to the NCBI record.

Helicobacter zhangjianzhongii NCBITaxon:2974574 DOI:10.3389/fgene.2023.1240581 Wang et al. reported both Helicobacter zhangjianzhongii isolates as positive for gamma-glutamyltransferase activity in the API Campy biochemical panel.

Discussions and Knowledge Gaps (1)

Open questions attached to this trait. Seeded by just knowledge-gap-scan and curated; see the corpus-wide index.

Resolve an exact external ontology class for gamma-glutamyltransferase activity before adding a TraitRecord xref.

CURATION TODO OPEN gamma-glutamyltransferase-activity-xref-gap · raised by codex · 2026-09-12

Not yet attached to a section of this record — a curator sets attaches_to (e.g. causal_graphs#some_edge) so the gap shows beside the mechanism it concerns.

GO:0003840 gamma-glutamyltransferase activity is obsolete, and its replacement GO:0036374 glutathione hydrolase activity denotes a glutathione-hydrolysis molecular function rather than the organism-level gamma-glutamyltransferase/glutathione-hydrolase phenotype. GO:0036374 is appropriate as a causal-node grounding when a graph needs that hydrolysis half-reaction, not as an equivalent TraitRecord xref.

Curation history

2026-09-12T06:47:37Z · MINTED_TRAITMECH_ID · codex
Minted gamma-glutamyltransferase activity as a URL/DOI-backed TraitRecord after a repository-wide duplicate review covering ignored and hidden files; METPO has no exact gamma-glutamyltransferase activity class yet and the placeholder is reserved in proposals/metpo_traitmech_v37.