Reaction: 2 L-glutamate + 2 oxidized ferredoxin = L-glutamine + 2-oxoglutarate + 2 reduced ferredoxin + 2 H+ (overall reaction)
(1a) L-glutamate + NH3 = L-glutamine + H2O
(1b) L-glutamate + 2 oxidized ferredoxin + H2O = NH3 + 2-oxoglutarate + 2 reduced ferredoxin + 2 H+
For diagram of reaction click here.
Other name(s): ferredoxin-dependent glutamate synthase; ferredoxin-glutamate synthase; glutamate synthase (ferredoxin-dependent)
Systematic name: L-glutamate:ferredoxin oxidoreductase (transaminating)
Comments: Binds a [3Fe-4S] cluster as well as FAD and FMN. The protein is composed of two domains, one hydrolysing L-glutamine to NH3 and L-glutamate (cf. EC 220.127.116.11, glutaminase), the other combining the produced NH3 with 2-oxoglutarate to produce a second molecule of L-glutamate. The NH3 is channeled through a 24 Å channel in the active protein. No hydrolysis of glutamine takes place without ferredoxin and 2-oxoglutarate being bound to the protein [5,6].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 62213-56-3
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