1i1q
From Proteopedia
(New page: 200px<br /><applet load="1i1q" size="450" color="white" frame="true" align="right" spinBox="true" caption="1i1q, resolution 1.90Å" /> '''STRUCTURE OF THE COO...) |
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- | [[Image:1i1q.gif|left|200px]]<br /><applet load="1i1q" size=" | + | [[Image:1i1q.gif|left|200px]]<br /><applet load="1i1q" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1i1q, resolution 1.90Å" /> | caption="1i1q, resolution 1.90Å" /> | ||
'''STRUCTURE OF THE COOPERATIVE ALLOSTERIC ANTHRANILATE SYNTHASE FROM SALMONELLA TYPHIMURIUM'''<br /> | '''STRUCTURE OF THE COOPERATIVE ALLOSTERIC ANTHRANILATE SYNTHASE FROM SALMONELLA TYPHIMURIUM'''<br /> | ||
==Overview== | ==Overview== | ||
- | We have determined the X-ray crystal structure of the cooperative | + | We have determined the X-ray crystal structure of the cooperative anthranilate synthase heterotetramer from Salmonella typhimurium at 1.9 A resolution with the allosteric inhibitor l-tryptophan bound to a regulatory site in the TrpE subunit. Tryptophan binding orders a loop that in turn stabilizes the inactive T state of the enzyme by restricting closure of the active site cleft. Comparison with the structure of the unliganded, noncooperative anthranilate synthase heterotetramer from Sulfolobus solfataricus shows that the two homologs have completely different quarternary structures, even though their functional dimer pairs are structurally similar, consistent with differences in the cooperative behavior of the enzymes. The structural model rationalizes mutational and biochemical studies of the enzyme and establishes the structural differences between cooperative and noncooperative anthranilate synthase homologs. |
==About this Structure== | ==About this Structure== | ||
- | 1I1Q is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Salmonella_typhimurium Salmonella typhimurium] with TRP as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Anthranilate_synthase Anthranilate synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.3.27 4.1.3.27] Full crystallographic information is available from [http:// | + | 1I1Q is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Salmonella_typhimurium Salmonella typhimurium] with <scene name='pdbligand=TRP:'>TRP</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Anthranilate_synthase Anthranilate synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.3.27 4.1.3.27] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1I1Q OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Salmonella typhimurium]] | [[Category: Salmonella typhimurium]] | ||
- | [[Category: Eck, M | + | [[Category: Eck, M J.]] |
- | [[Category: Morollo, A | + | [[Category: Morollo, A A.]] |
[[Category: TRP]] | [[Category: TRP]] | ||
[[Category: tryptophan biosynthesis]] | [[Category: tryptophan biosynthesis]] | ||
- | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:07:09 2008'' |
Revision as of 11:07, 21 February 2008
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STRUCTURE OF THE COOPERATIVE ALLOSTERIC ANTHRANILATE SYNTHASE FROM SALMONELLA TYPHIMURIUM
Overview
We have determined the X-ray crystal structure of the cooperative anthranilate synthase heterotetramer from Salmonella typhimurium at 1.9 A resolution with the allosteric inhibitor l-tryptophan bound to a regulatory site in the TrpE subunit. Tryptophan binding orders a loop that in turn stabilizes the inactive T state of the enzyme by restricting closure of the active site cleft. Comparison with the structure of the unliganded, noncooperative anthranilate synthase heterotetramer from Sulfolobus solfataricus shows that the two homologs have completely different quarternary structures, even though their functional dimer pairs are structurally similar, consistent with differences in the cooperative behavior of the enzymes. The structural model rationalizes mutational and biochemical studies of the enzyme and establishes the structural differences between cooperative and noncooperative anthranilate synthase homologs.
About this Structure
1I1Q is a Protein complex structure of sequences from Salmonella typhimurium with as ligand. Active as Anthranilate synthase, with EC number 4.1.3.27 Full crystallographic information is available from OCA.
Reference
Structure of the cooperative allosteric anthranilate synthase from Salmonella typhimurium., Morollo AA, Eck MJ, Nat Struct Biol. 2001 Mar;8(3):243-7. PMID:11224570
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