User:Kay Owosela
From Proteopedia
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| - | Glutamine Synthetase has 622 and dodecameric symmetry, which could be split in to twelve equal parts. | + | Glutamine Synthetase has 622 and dodecameric symmetry, which could be split in to twelve equal parts. Symmetry can be viewed as <scene name='User:Kay_Owosela/Sandwich_symmetry/5'>"sandwich symmetry"</scene> and <scene name='User:Kay_Owosela/Star_shaped_symmetry/1'>"star of David symmetry"</scene>. Each subunit has an <scene name='User:Kay_Owosela/Active_site_location/1'>active site</scene> are examples of how the 622 symmetry could be modeled. The active site of glutamine synthetase lies primarily around three manganese atoms. It is surrounded by three important ligands: Phosphinothricin, ADP, TL as labeled in the applet. ADP is short for Adenosite Diphosphate. And the metal ion, Thallium is also labeled in the applet. |
= Reference = | = Reference = | ||
Revision as of 03:31, 21 December 2008
Biol 430
Biology Major
Partners: Delo Sarr, Mustafa Husain
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Contents |
Jmol practice
Backbone with ligand
Labeled Ligands in Chain A
Active Site with Amino Acid Residues
Connection between Chain F residue 63 and Chain G residue 319
Stoichiometry
Quarternary Structure
The enzyme Glutamine Synthetase is made up of twelve subunits. The structure consists of two identical hexameric rings held together by hydrophobic and hydrogen bonding forces. The N-terminal helix of each subunit is exposed to hydrophilic solvent, where as the C-terminal is enshrouded in hydrophobic regions within the helical structure of the rings. The central channel is linked together by six four-stranded anti-parallel L-sheets which along with the twelve monomers enhance the stability of the protein structure.
Quarternary Interactions
Interacting subunits are connected through couple of different type of interactions, such as: Hydrogen Bonds, and Non-bonded contacts. Each subunit has area’s that are proportional to the surface area of the corresponding protein chains. Each subunit only interacts with four other protomers in the protein.
Subunit Connections:
A is bonded to four subunits, F, G, H, and B through hydrogen bonds and non-bonding interactions
B is bonded to four subunits, H, I, A, and C through hydrogen bonds and non-bonding interactions
C is bonded to four subunits, B, D, I, and J through hydrogen bonds and non-bonding interactions
D is bonded to four subunits, C, I, J, and K through hydrogen bonds and non-bonding interactions
E is bonded to four subunits, L, F, D, and K through hydrogen bonds and non-bonding interactions
F is bonded to four subunits, A, G, L, and E through hydrogen bonds and non-bonding interactions
G is bonded to four subunits, A, H, L, and F through hydrogen bonds and non-bonding interactions
H is bonded to four subunits, A, B, G, and L through hydrogen bonds and non-bonding interactions
I is bonded to four subunits, B, H, C, and J through hydrogen bonds and non-bonding interactions
J is bonded to four subunits, I, C, D, and K through hydrogen bonds and non-bonding interactions
K is bonded to four subunits, E, L, J, and D through hydrogen bonds and non-bonding interactions
L is bonded to four subunits, E, F, A, and G through hydrogen bonds and non-bonding interactions
Active Site
Glutamine Synthetase has 622 and dodecameric symmetry, which could be split in to twelve equal parts. Symmetry can be viewed as and . Each subunit has an are examples of how the 622 symmetry could be modeled. The active site of glutamine synthetase lies primarily around three manganese atoms. It is surrounded by three important ligands: Phosphinothricin, ADP, TL as labeled in the applet. ADP is short for Adenosite Diphosphate. And the metal ion, Thallium is also labeled in the applet.
Reference
1. Eisenberg, David and Gill, Harindarpal and Pfluegl, Gaston and Rotstein, Sergio. “Structure-function relationships of glutamine synthetases.” Elsevier, archives of biochemistry and biophysics 1477(Dec 1999):122-123.
2. Eisenberg, Gill. "Crystal structure of glutamine synthetase from salmonella typhimurium with thallium ions" PDBsum. european bioinformatics institute 2006-2008. <http://www.ebi.ac.uk/thornton-srv/databases/cgi-bin/pdbsum/GetPage.pl?pdbcode=1f1h&template=main.html>
