IUBMB Enzyme Nomenclature


Accepted name: glutamine synthetase

Reaction: ATP + L-glutamate + NH3 = ADP + phosphate + L-glutamine

For diagram of reaction click here.

Other name(s): glutamate—ammonia ligase; glutamylhydroxamic synthetase; L-glutamine synthetase; GS

Systematic name: L-glutamate:ammonia ligase (ADP-forming)

Comments: Glutamine synthetase, which catalyses the incorporation of ammonium into glutamate, is a key enzyme of nitrogen metabolism found in all domains of life. Several types have been described, differing in their oligomeric structures and cofactor requirements.

Links to other databases: BRENDA, EXPASY, GTD, KEGG, MetaCyc, PDB, CAS registry number: 9023-70-5


1. Elliott, W.H. Isolation of glutamine synthetase and glutamotransferase from green peas. J. Biol. Chem. 201 (1953) 661-672. [PMID: 13061404]

2. Fry, B.A. Glutamine synthesis by Micrococcus pyogenes var. aureus. Biochem. J. 59 (1955) 579-589. [PMID: 14363150]

3. Lajtha, A., Mela, P. and Waelsch, H. Manganese-dependent glutamotransferase. J. Biol. Chem. 205 (1953) 553-564. [PMID: 13129232]

4. Meister, A. Glutamine synthesis. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Eds), The Enzymes, 2nd edn, vol. 6, Academic Press, New York, 1962, pp. 443-468.

5. Woolfolk, C.A., Shapiro, B. and Stadtman, E.R. Regulation of glutamine synthetase. I. Purification and properties of glutamine synthetase from Escherichia coli. Arch. Biochem. Biophys. 116 (1966) 177-192. [PMID: 5336023]

6. Kumada, Y., Benson, D.R., Hillemann, D., Hosted, T.J., Rochefort, D.A., Thompson, C.J., Wohlleben, W. and Tateno, Y. Evolution of the glutamine synthetase gene, one of the oldest existing and functioning genes. Proc. Natl. Acad. Sci. USA 90 (1993) 3009-3013. [PMID: 8096645]

7. Llorca, O., Betti, M., Gonzalez, J.M., Valencia, A., Marquez, A.J. and Valpuesta, J.M. The three-dimensional structure of an eukaryotic glutamine synthetase: functional implications of its oligomeric structure. J. Struct. Biol. 156 (2006) 469-479. [PMID: 16884924]

8. Martinez-Espinosa, R.M., Esclapez, J., Bautista, V. and Bonete, M.J. An octameric prokaryotic glutamine synthetase from the haloarchaeon Haloferax mediterranei. FEMS Microbiol. Lett. 264 (2006) 110-116. [PMID: 17020556]

[EC created 1961, modified 2016]

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