This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.


Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.


2ri6

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
(New page: 200px<br /><applet load="2ri6" size="450" color="white" frame="true" align="right" spinBox="true" caption="2ri6, resolution 1.680&Aring;" /> '''Crystal Structure o...)
Current revision (09:22, 21 February 2024) (edit) (undo)
 
(14 intermediate revisions not shown.)
Line 1: Line 1:
-
[[Image:2ri6.jpg|left|200px]]<br /><applet load="2ri6" size="450" color="white" frame="true" align="right" spinBox="true"
 
-
caption="2ri6, resolution 1.680&Aring;" />
 
-
'''Crystal Structure of S112A mutant of a C-C hydrolase, BphD from Burkholderia xenovorans LB400'''<br />
 
-
==Overview==
+
==Crystal Structure of S112A mutant of a C-C hydrolase, BphD from Burkholderia xenovorans LB400==
-
BphD of Burkholderia xenovorans LB400 catalyzes an unusual C-C bond, hydrolysis of 2-hydroxy-6-oxo-6-phenyl-hexa-2,4-dienoic acid (HOPDA) to, afford benzoic acid and 2-hydroxy-2,4-pentadienoic acid (HPD). An, enol-keto tautomerization has been proposed to precede hydrolysis via a, gem-diol intermediate. The role of the canonical 'catalytic triad', (Ser-112, His-265, Asp-237) in mediating these two half-reactions remains, unclear. We previously reported that the BphD-catalyzed hydrolysis of, HOPDA (max = 434 nm for the free enolate) proceeds via an unidentified, intermediate with a red-shifted absorption spectrum (max = 492 nm), (Horsman et al. (2006), Biochemistry 45, 11071). Here we demonstrate that, the Ser112Ala variant (S112A) generates and traps a similar intermediate, (max = 506 nm) with a similar rate, 1/t ~ 500 s-1. The crystal structure, of the S112A:HOPDA complex at 1.8 A resolution identified this, intermediate as the keto tautomer, (E)-2,6-dioxo-6-phenyl-hex-3-enoate., This keto tautomer did not accumulate in either the H265A or the, S112A/H265A double variants, indicating that His-265 catalyzes, tautomerization. Consistent with this role, the wild type and S112A, enzymes catalyzed tautomerization of the product HPD, while H265A variants, did not. This study thus identifies a keto intermediate, and demonstrates, that the catalytic triad histidine catalyzes the tautomerization, half-reaction, expanding the role of this residue from its purely, hydrolytic function in other serine hydrolases. Finally, the S112A:HOPDA, crystal structure is more consistent with hydrolysis occurring via an, acyl-enzyme intermediate than a gem-diol intermediate as solvent molecules, have poor access to C6, and the closest ordered water is 7 A away.
+
<StructureSection load='2ri6' size='340' side='right'caption='[[2ri6]], [[Resolution|resolution]] 1.68&Aring;' scene=''>
-
 
+
== Structural highlights ==
-
==About this Structure==
+
<table><tr><td colspan='2'>[[2ri6]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Paraburkholderia_xenovorans_LB400 Paraburkholderia xenovorans LB400]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=2pu6 2pu6]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2RI6 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2RI6 FirstGlance]. <br>
-
2RI6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Burkholderia_xenovorans Burkholderia xenovorans] with NA and MLI as [http://en.wikipedia.org/wiki/ligands ligands]. This structure superseeds the now removed PDB entry 2PU6. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2RI6 OCA].
+
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.68&#8491;</td></tr>
-
 
+
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MLI:MALONATE+ION'>MLI</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene></td></tr>
-
==Reference==
+
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2ri6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ri6 OCA], [https://pdbe.org/2ri6 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ri6 RCSB], [https://www.ebi.ac.uk/pdbsum/2ri6 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ri6 ProSAT]</span></td></tr>
-
The tautomeric half-reaction of BphD, A C-C bond hydrolase: Kinetic and structural evidence supporting a key role for histidine 265 of the catalytic triad., Horsman GP, Bhowmik S, Seah SY, Kumar P, Bolin JT, Eltis LD, J Biol Chem. 2007 Apr 18;. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17442675 17442675]
+
</table>
-
[[Category: Burkholderia xenovorans]]
+
== Function ==
-
[[Category: Single protein]]
+
[https://www.uniprot.org/uniprot/BPHD_PARXL BPHD_PARXL] Catalyzes an unusual C-C bond hydrolysis of 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA) to produce benzoic acid and 2-hydroxy-2,4-pentadienoic acid (HPD).<ref>PMID:16964968</ref>
-
[[Category: Bhowmik, S.]]
+
== Evolutionary Conservation ==
-
[[Category: Bolin, J.T.]]
+
[[Image:Consurf_key_small.gif|200px|right]]
-
[[Category: MLI]]
+
Check<jmol>
-
[[Category: NA]]
+
<jmolCheckbox>
-
[[Category: aromatic hydrocarbons catabolism]]
+
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ri/2ri6_consurf.spt"</scriptWhenChecked>
-
[[Category: c-c bond hydrolase]]
+
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
-
[[Category: hydrolase]]
+
<text>to colour the structure by Evolutionary Conservation</text>
-
 
+
</jmolCheckbox>
-
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Sun Nov 25 08:56:18 2007''
+
</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/main_output.php?pdb_ID=2ri6 ConSurf].
 +
<div style="clear:both"></div>
 +
== References ==
 +
<references/>
 +
__TOC__
 +
</StructureSection>
 +
[[Category: Large Structures]]
 +
[[Category: Paraburkholderia xenovorans LB400]]
 +
[[Category: Bhowmik S]]
 +
[[Category: Bolin JT]]

Current revision

Crystal Structure of S112A mutant of a C-C hydrolase, BphD from Burkholderia xenovorans LB400

PDB ID 2ri6

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools