Glutamate synthase (NADPH)

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glutamate synthase (NADPH)
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Glutamate synthase dodekamer, Azospirillum br.
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EC no. 1.4.1.13
CAS no. 37213-53-9
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In enzymology, a glutamate synthase (NADPH) (EC 1.4.1.13) is an enzyme that catalyzes the chemical reaction

Contents

L-glutamine + 2-oxoglutarate + NADPH + H+ 2 L-glutamate + NADP+

Thus, the four substrates of this enzyme are L-glutamine, 2-oxoglutarate (α-ketoglutarate), NADPH, and H+, whereas the two products are L-glutamate and NADP+.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH2 group of donors with NAD+ or NADP+ as acceptor. This enzyme participates in glutamate metabolism and nitrogen metabolism. It has 5 cofactors: FAD, Iron, FMN, Sulfur, and Iron-sulfur.

It occurs in bacteria and plants but not animals, and is important as it provides glutamate for the glutamine synthetase reaction. [1] [2]

Nomenclature

The systematic name of this enzyme class is L-glutamate:NADP+ oxidoreductase (transaminating). Other names in common use include:

Structural studies

As of late 2007, only one structure has been solved for this class of enzymes, with the PDB accession code 1EA0.

See also

Related Research Articles

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References

  1. Temple SJ, Vance CP, Gantt JS (1998). "Glutamate synthase and nitrogen assimilation". Trends in Plant Science. 3 (2): 51–56. doi:10.1016/S1360-1385(97)01159-X.
  2. Vanoni MA, Curti B (May 2008). "Structure-function studies of glutamate synthases: a class of self-regulated iron-sulfur flavoenzymes essential for nitrogen assimilation". IUBMB Life. 60 (5): 287–300. doi: 10.1002/iub.52 . PMID   18421771. S2CID   33617681.

Further reading