2j9z: Difference between revisions

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[[Image:~~2j9z~~.~~png~~|~~left~~|~~200px~~]]

==TRYPTOPHAN SYNTHASE T110 MUTANT COMPLEX==

== Structural highlights ==

<table><tr><td colspan='2'>[[2j9z]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Salmonella_enterica_subsp._enterica_serovar_typhimurium Salmonella enterica subsp. enterica serovar typhimurium]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2J9Z OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2J9Z FirstGlance]. <br>

</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene><br>

<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Tryptophan_synthase Tryptophan synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.20 4.2.1.20] </span></td></tr>

<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2j9z FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2j9z OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2j9z RCSB], [http://www.ebi.ac.uk/pdbsum/2j9z PDBsum]</span></td></tr>

<table>

== Evolutionary Conservation ==

[[Image:Consurf_key_small.gif|200px|right]]

Check<jmol>

<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/j9/2j9z_consurf.spt"</scriptWhenChecked>

<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>

<text>to colour the structure by Evolutionary Conservation</text>

</jmolCheckbox>

</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf].

== Publication Abstract from PubMed ==

In the PLP-requiring alpha2beta2 tryptophan synthase complex, recognition of the substrate l-Ser at the beta-site includes a loop structure (residues beta110-115) extensively H-bonded to the substrate alpha-carboxylate. To investigate the relationship of this subsite to catalytic function and to the regulation of substrate channeling, two loop mutants were constructed: betaThr110 --> Val, and betaGln114 --> Asn. The betaT110V mutation greatly impairs both catalytic activity in the beta-reaction, and allosteric communication between the alpha- and beta-sites. The crystal structure of the betaT110V mutant shows that the modified l-Ser carboxylate subsite has altered protein interactions that impair beta-site catalysis and the communication of allosteric signals between the alpha- and beta-sites. Purified betaQ114N consists of two species of mutant protein, one with a reddish color (lambdamax = 506 nm). The reddish species is unable to react with l-Ser. The second betaQ114N species displays significant catalytic activities; however, intermediates obtained on reaction with substrate l-Ser and substrate analogues exhibit perturbed UV/vis absorption spectra. Incubation with l-Ser results in the formation of an inactive species during the first 15 min with lambdamax approximately 320 nm, followed by a slower conversion over 24 h to the species with lambdamax = 506 nm. The 320 and 506 nm species originate from conversion of the alpha-aminoacrylate external aldimine to the internal aldimine and alpha-aminoacrylate, followed by the nucleophilic attack of alpha-aminoacrylate on C-4' of the internal aldimine to give a covalent adduct with PLP. Subsequent treatment with sodium hydroxide releases a modified coenzyme consisting of a vinylglyoxylic acid moiety linked through C-4' to the 4-position of the pyridine ring. We conclude that the shortening of the side chain accompanying the replacement of beta114-Gln by Asn relaxes the steric constraints that prevent this reaction in the wild-type enzyme. This study reveals a new layer of structure-function interactions essential for reaction specificity in tryptophan synthase.

~~{{STRUCTURE_2j9z| PDB=2j9z | SCENE= }}~~

BetaQ114N and betaT110V mutations reveal a critically important role of the substrate alpha-carboxylate site in the reaction specificity of tryptophan synthase.,Blumenstein L, Domratcheva T, Niks D, Ngo H, Seidel R, Dunn MF, Schlichting I Biochemistry. 2007 Dec 11;46(49):14100-16. Epub 2007 Nov 16. PMID:18004874<ref>PMID:18004874</ref>

~~===TRYPTOPHAN SYNTHASE T110 MUTANT COMPLEX===~~

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>

</div>

~~{{ABSTRACT_PUBMED_18004874}}~~

~~==About this Structure==~~

~~[[2j9z]] is~~ a ~~2 chain structure with sequence from [http://en.wikipedia.org/wiki/Salmonella_enterica_subsp~~.~~_enterica_serovar_typhimurium Salmonella enterica subsp~~. ~~enterica serovar typhimurium]~~. ~~Full crystallographic information is available from [http://oca.weizmann.ac.il~~/~~oca-bin/ocashort?id=2J9Z OCA].~~

==See Also==

*[[Tryptophan synthase|Tryptophan synthase]]

== References ==

==~~Reference~~==

<~~ref group="xtra">PMID:018004874<~~/~~ref~~><~~references group="xtra"~~/>

__TOC__

</StructureSection>

[[Category: Salmonella enterica subsp. enterica serovar typhimurium]]

[[Category: Tryptophan synthase]]

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@@ Line 1: / Line 1: @@
-[[Image:2j9z.png|left|200px]]
+==TRYPTOPHAN SYNTHASE T110 MUTANT COMPLEX==
+<StructureSection load='2j9z' size='340' side='right' caption='[[2j9z]], [[Resolution|resolution]] 1.80&Aring;' scene=''>
+== Structural highlights ==
+<table><tr><td colspan='2'>[[2j9z]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Salmonella_enterica_subsp._enterica_serovar_typhimurium Salmonella enterica subsp. enterica serovar typhimurium]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2J9Z OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2J9Z FirstGlance]. <br>
+</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene><br>
+<tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1a50|1a50]], [[1a5a|1a5a]], [[1a5b|1a5b]], [[1a5s|1a5s]], [[1beu|1beu]], [[1bks|1bks]], [[1c29|1c29]], [[1c8v|1c8v]], [[1c9d|1c9d]], [[1cw2|1cw2]], [[1cx9|1cx9]], [[1fuy|1fuy]], [[1k3u|1k3u]], [[1k7e|1k7e]], [[1k7f|1k7f]], [[1k7x|1k7x]], [[1k8x|1k8x]], [[1k8y|1k8y]], [[1k8z|1k8z]], [[1kfb|1kfb]], [[1kfc|1kfc]], [[1kfe|1kfe]], [[1kfj|1kfj]], [[1kfk|1kfk]], [[1qop|1qop]], [[1qoq|1qoq]], [[1tjp|1tjp]], [[1ttp|1ttp]], [[1ubs|1ubs]], [[1wbj|1wbj]], [[2cle|2cle]], [[2clf|2clf]], [[2cli|2cli]], [[2clk|2clk]], [[2cll|2cll]], [[2clm|2clm]], [[2clo|2clo]], [[2j9x|2j9x]], [[2j9y|2j9y]], [[2trs|2trs]], [[2tsy|2tsy]], [[2tys|2tys]], [[2wsy|2wsy]]</td></tr>
+<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Tryptophan_synthase Tryptophan synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.20 4.2.1.20] </span></td></tr>
+<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2j9z FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2j9z OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2j9z RCSB], [http://www.ebi.ac.uk/pdbsum/2j9z PDBsum]</span></td></tr>
+<table>
+== Evolutionary Conservation ==
+[[Image:Consurf_key_small.gif|200px|right]]
+Check<jmol>
+  <jmolCheckbox>
+    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/j9/2j9z_consurf.spt"</scriptWhenChecked>
+    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
+    <text>to colour the structure by Evolutionary Conservation</text>
+  </jmolCheckbox>
+</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf].
+<div style="clear:both"></div>
+<div style="background-color:#fffaf0;">
+== Publication Abstract from PubMed ==
+In the PLP-requiring alpha2beta2 tryptophan synthase complex, recognition of the substrate l-Ser at the beta-site includes a loop structure (residues beta110-115) extensively H-bonded to the substrate alpha-carboxylate. To investigate the relationship of this subsite to catalytic function and to the regulation of substrate channeling, two loop mutants were constructed: betaThr110 --&gt; Val, and betaGln114 --&gt; Asn. The betaT110V mutation greatly impairs both catalytic activity in the beta-reaction, and allosteric communication between the alpha- and beta-sites. The crystal structure of the betaT110V mutant shows that the modified l-Ser carboxylate subsite has altered protein interactions that impair beta-site catalysis and the communication of allosteric signals between the alpha- and beta-sites. Purified betaQ114N consists of two species of mutant protein, one with a reddish color (lambdamax = 506 nm). The reddish species is unable to react with l-Ser. The second betaQ114N species displays significant catalytic activities; however, intermediates obtained on reaction with substrate l-Ser and substrate analogues exhibit perturbed UV/vis absorption spectra. Incubation with l-Ser results in the formation of an inactive species during the first 15 min with lambdamax approximately 320 nm, followed by a slower conversion over 24 h to the species with lambdamax = 506 nm. The 320 and 506 nm species originate from conversion of the alpha-aminoacrylate external aldimine to the internal aldimine and alpha-aminoacrylate, followed by the nucleophilic attack of alpha-aminoacrylate on C-4' of the internal aldimine to give a covalent adduct with PLP. Subsequent treatment with sodium hydroxide releases a modified coenzyme consisting of a vinylglyoxylic acid moiety linked through C-4' to the 4-position of the pyridine ring. We conclude that the shortening of the side chain accompanying the replacement of beta114-Gln by Asn relaxes the steric constraints that prevent this reaction in the wild-type enzyme. This study reveals a new layer of structure-function interactions essential for reaction specificity in tryptophan synthase.
-{{STRUCTURE_2j9z|  PDB=2j9z  |  SCENE=  }}
+BetaQ114N and betaT110V mutations reveal a critically important role of the substrate alpha-carboxylate site in the reaction specificity of tryptophan synthase.,Blumenstein L, Domratcheva T, Niks D, Ngo H, Seidel R, Dunn MF, Schlichting I Biochemistry. 2007 Dec 11;46(49):14100-16. Epub 2007 Nov 16. PMID:18004874<ref>PMID:18004874</ref>
-===TRYPTOPHAN SYNTHASE T110 MUTANT COMPLEX===
+From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
+</div>
-{{ABSTRACT_PUBMED_18004874}}
-==About this Structure==
-[[2j9z]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Salmonella_enterica_subsp._enterica_serovar_typhimurium Salmonella enterica subsp. enterica serovar typhimurium]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2J9Z OCA].
 ==See Also==
 *[[Tryptophan synthase|Tryptophan synthase]]
+== References ==
-==Reference==
+<references/>
-<ref group="xtra">PMID:018004874</ref><references group="xtra"/>
+__TOC__
+</StructureSection>
 [[Category: Salmonella enterica subsp. enterica serovar typhimurium]]
 [[Category: Tryptophan synthase]]