Sandbox2qc8
From Proteopedia
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==Glutamine Synthetase: Secondary structures== | ==Glutamine Synthetase: Secondary structures== | ||
| - | Glutamine synthetase is composed of 12 <scene name='Sandbox2qc8/Identical_subunits/1'>identical subunits</scene>. Each subunit is composed of 15 <scene name='Sandbox2qc8/15_alpha_helices/1'>alpha helices</scene> and <scene name='Sandbox2qc8/Pdb_defined_beta_strands/1'> | + | Glutamine synthetase is composed of 12 <scene name='Sandbox2qc8/Identical_subunits/1'>identical subunits</scene>. Each subunit is composed of 15 <scene name='Sandbox2qc8/15_alpha_helices/1'>alpha helices</scene> and 15 <scene name='Sandbox2qc8/Pdb_defined_beta_strands/1'>beta strands</scene>. Each subunit binds 2 Mn for a total of <scene name='Sandbox2qc8/Ligand_mn/1'>24 Mn</scene> per Glutamine Synthetase. |
The β-strands are arranged into 5 <scene name='Sandbox2qc8/Pdb_defined_beta_strands/1'>beta sheets</scene>. In addition, there are 5 <scene name='Sandbox2qc8/Hairpins/1'>β-hairpins</scene> and 5 <scene name='Sandbox2qc8/Bulges/1'>β-bulges</scene>. <ref>European Bioinformatics Institute, Ligase(amide synthetase), http://www.ebi.ac.uk/thornton-srv/databases/cgi-bin/pdbsum/GetPage.pl?pdbcode=2gls, Accessed December 18, 2008.</ref> β-bulges are distortions in β-sheets resulting from the addition of an extra residue due to mutation. Their presence allows the proteins to conserve their structure by maintaining the hydrogen bond pattern.<ref name="wiley">Donald Voet, Judith G. Voet, Charlotte W. Pratt. Fundamentals of Biochemistry life at the molecular level. New Jersey: Wiley,2006.</ref> At the level of the backbone structure, these β-bulges can cause a simple aneurysm of the β-sheet. Furthermore, each β-bulge can cause a β-sheet to fold over and cross itself.<br> | The β-strands are arranged into 5 <scene name='Sandbox2qc8/Pdb_defined_beta_strands/1'>beta sheets</scene>. In addition, there are 5 <scene name='Sandbox2qc8/Hairpins/1'>β-hairpins</scene> and 5 <scene name='Sandbox2qc8/Bulges/1'>β-bulges</scene>. <ref>European Bioinformatics Institute, Ligase(amide synthetase), http://www.ebi.ac.uk/thornton-srv/databases/cgi-bin/pdbsum/GetPage.pl?pdbcode=2gls, Accessed December 18, 2008.</ref> β-bulges are distortions in β-sheets resulting from the addition of an extra residue due to mutation. Their presence allows the proteins to conserve their structure by maintaining the hydrogen bond pattern.<ref name="wiley">Donald Voet, Judith G. Voet, Charlotte W. Pratt. Fundamentals of Biochemistry life at the molecular level. New Jersey: Wiley,2006.</ref> At the level of the backbone structure, these β-bulges can cause a simple aneurysm of the β-sheet. Furthermore, each β-bulge can cause a β-sheet to fold over and cross itself.<br> | ||
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Glutamine Synthetase is covalently modified by the addition of Adenosine monophosphate at Tyrosine 397 which is contained in the | Glutamine Synthetase is covalently modified by the addition of Adenosine monophosphate at Tyrosine 397 which is contained in the | ||
| - | <scene name='Sandbox2qc8/Tyr_397_beta_loop/1'> | + | <scene name='Sandbox2qc8/Tyr_397_beta_loop/1'>adenylation loop</scene><ref>Eisenberg, D., et.al., Structure-function relationships of glutamine synthetases, Biochim Biophys Acta 2000: 1477, 122-145</ref>. In addition, β-loops protrude into the <scene name='Sandbox2qc8/12_loops_of_center/1'>aqueous central channel</scene>, allowing for additional quaternary stability.<ref name="resolution">Yamashita, M. M., et.al., Refined Atolnic Model of Glutamine Synthetase at 3.5 A Resolution, J Biol Chem 1989 264: 17681-17690.</ref> |
Revision as of 04:49, 20 December 2008
Glutamine Synthetase: Secondary structures
Glutamine synthetase is composed of 12 . Each subunit is composed of 15 and 15 . Each subunit binds 2 Mn for a total of per Glutamine Synthetase.
The β-strands are arranged into 5 . In addition, there are 5 and 5 . [1] β-bulges are distortions in β-sheets resulting from the addition of an extra residue due to mutation. Their presence allows the proteins to conserve their structure by maintaining the hydrogen bond pattern.[2] At the level of the backbone structure, these β-bulges can cause a simple aneurysm of the β-sheet. Furthermore, each β-bulge can cause a β-sheet to fold over and cross itself.
Within each subunit there are 46 β-turns. These β-turns join secondary structures such as β-sheets and alpha helices when they need to abruptly change directions and usually occur at the protein surface.[2]
Glutamine Synthetase is covalently modified by the addition of Adenosine monophosphate at Tyrosine 397 which is contained in the [3]. In addition, β-loops protrude into the , allowing for additional quaternary stability.[4]
Each subunit has an exposed NH2 terminus and buried COOH terminus as part of a , colored in red. The helical thong is used as an anchor inside another subunit. [4]
The active site within the secondary structure can be called a "bifunnel," providing access to ATP and glutamate at opposing ends.[5]
The only ligand present is a pair of Mn ions (Manganese) that indicates the active site of each subunit of the dodecamer.
Glutamine synthetase contains the .
References
- ↑ European Bioinformatics Institute, Ligase(amide synthetase), http://www.ebi.ac.uk/thornton-srv/databases/cgi-bin/pdbsum/GetPage.pl?pdbcode=2gls, Accessed December 18, 2008.
- ↑ 2.0 2.1 Donald Voet, Judith G. Voet, Charlotte W. Pratt. Fundamentals of Biochemistry life at the molecular level. New Jersey: Wiley,2006.
- ↑ Eisenberg, D., et.al., Structure-function relationships of glutamine synthetases, Biochim Biophys Acta 2000: 1477, 122-145
- ↑ 4.0 4.1 Yamashita, M. M., et.al., Refined Atolnic Model of Glutamine Synthetase at 3.5 A Resolution, J Biol Chem 1989 264: 17681-17690.
- ↑ Eisenberg, D., et al., Structure-function relationships of glutamine synthetases, Biochimica et Biophysica Acta 1477 (2000), 122-145.
