Glutamate synthase, central-N (IPR006982)

Short name: Glu_synth_centr_N

Overlapping homologous superfamilies

Domain relationships



Glutamate synthase (GltS)1 is a key enzyme in the early stages of the assimilation of ammonia in bacteria, yeasts, and plants. In bacteria, L-glutamate is involved in osmoregulation, is the precursor for other amino acids, and can be the precursor for haem biosynthesis. In plants, GltS is especially essential in the reassimilation of ammonia released by photorespiration. On the basis of the amino acid sequence and the nature of the electron donor, three different classes of GltS can de defined as follows: 1) ferredoxin-dependent GltS (Fd-GltS), 2) NADPH-dependent GltS (NADPH-GltS), and 3) NADH-dependent GltS (properties of the three classes have been reviewed extensively [PMID: 10357231]). The enzyme is a complex iron-sulphur flavoprotein catalysing the reductive transfer of the amido nitrogen from L-glutamine to 2-oxoglutarate to form two molecules of L-glutamate via intramolecular channelling of ammonia from the amidotransferase domain to the FMN-binding domain.

Reaction of amidotransferase domain:

L-glutamine + H2O = L-glutamate + NH3

Reactions of FMN-binding domain:

2-oxoglutarate + NH3 = 2-iminoglutarate + H2O 2e + FMNox = FMNred 2-iminoglutarate + FMNred = L-glutamate + FMNox

The central domain of glutamate synthase connects the N-terminal amidotransferase domain with the FMN-binding domain and has an alpha/beta overall topology [PMID: 11967268].

GO terms

Biological Process

GO:0006807 nitrogen compound metabolic process
GO:0055114 oxidation-reduction process

Molecular Function

GO:0015930 glutamate synthase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.