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Rhiannon Khela

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spinqualitylabelsall models PDB ID 2gls Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image
2gls, resolution 3.50Å ()
Ligands:
Activity:	Glutamate--ammonia ligase, with EC number 6.3.1.2
Structural annotation: Resources: CATH : 2Glsa02, 2Glsa01, 2Glsb02, 2Glsb01, 2Glsc01, 2Glsc02, 2Glsd02, 2Glsd01, 2Glse02, 2Glse01, 2Glsf02, 2Glsf01, 2Glsg01, 2Glsg02, 2Glsh02, 2Glsh01, 2Glsi02, 2Glsi01, 2Glsj01, 2Glsj02, 2Glsk01, 2Glsk02, 2Glsl02, 2Glsl01 InterPro : Ipr014746, Ipr008146, Ipr001637, Ipr008147, Ipr004809 Pfam : PF00120, PF03951 SCOP : d2glsa2, d2glsa1, d2glsb2, d2glsb1, d2glsc1, d2glsc2, d2glsd2, d2glsd1, d2glse2, d2glse1, d2glsf1, d2glsf2, d2glsg2, d2glsg1, d2glsh2, d2glsh1, d2glsi2, d2glsi1, d2glsj2, d2glsj1, d2glsk1, d2glsk2, d2glsl2, d2glsl1 UniProt : P0A1P6
Functional annotation: Cellular component: cytoplasm Biological process: nitrogen compound metabolic process glutamine biosynthetic process nitrogen fixation Molecular function: ligase activity nucleotide binding glutamate-ammonia ligase activity catalytic activity
Evolutionary conservation: Toggle Conservation Colors: Rows = identical sequences: Further Information: Caveats, Explanation, Complete Results at ConSurfDB
Resources:	FirstGlance, OCA, PDBsum, RCSB
Coordinates:	save as pdb, mmCIF, xml

Image:2gls120.png

Contents 1 Structure 2 Classes 3 Function 4 References

Structure

An unrefined structure of glutamine synthetase is made of two layers, each containing 6 subunits, for a total of 12 subunits. ^[1] Each subunit contains an active site which is defined by a cylindrical shape formed by six antiparalel β starnds contributed by one subunit and two more strands by the neighbouring subunit.^[2] In each cylindrical active site there are two Mn2+ ions. Both are attached to three protein chains and two water molecules, one of the water molecules are shared by both Mn2+. The protein ligands attached to Mn 2+ 469 are: Glu-131, GLu-212 and Glu-220. On the other hand, the protein ligands attached to Mn2+ are: Glu-129, His-269 and Glu-357.

Classes

Glutamine synthetase has been described as having three destinctive types:^[3]

• Class I (GSI): Genes for this class have only been found in bacteria (eubacteria) and archaea (arhaebacteria)
• Class II (GSII): Genes for this class have only been found in eukaryotes anda few soil-dwelling bacteria.
• Class III (GSIII): Genes from this class have only been found in a few bacterial species.It is a hexamer of identical chains. It is much larger (about 700 amino acids) than the GSI (450 to 470 amino acids) or GSII (350 to 420 amino acids) enzymes.

Function

Glutamine synthetase is an essential enzyme in the cellular nitrogen metabolism and has been found to play a role in both ammonia assimilation and glutamine byosynthesis.^[4] Image:Glutamine-synthesis.jpg

References

1. ↑ Yamashita MM, Almassy RJ, Janson CA, Cascio D, Eisenberg D. Refined atomic model of glutamine synthetase at 3.5 A resolution. J Biol Chem. 1989 Oct 25;264(30):17681-90. PMID:2572586
2. ↑ Yamashita MM, Almassy RJ, Janson CA, Cascio D, Eisenberg D. Refined atomic model of glutamine synthetase at 3.5 A resolution. J Biol Chem. 1989 Oct 25;264(30):17681-90. PMID:2572586
3. ↑ Brown JR, Masuchi Y, Robb FT, Doolittle WF. Evolutionary relationships of bacterial and archaeal glutamine synthetase genes. J Mol Evol. 1994 Jun;38(6):566-76. PMID:7916055
4. ↑ Kumada Y, Benson DR, Hillemann D, Hosted TJ, Rochefort DA, Thompson CJ, Wohlleben W, Tateno Y. Evolution of the glutamine synthetase gene, one of the oldest existing and functioning genes. Proc Natl Acad Sci U S A. 1993 Apr 1;90(7):3009-13. PMID:8096645