1gsq: Difference between revisions
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< | ==THREE-DIMENSIONAL STRUCTURE, CATALYTIC PROPERTIES AND EVOLUTION OF A SIGMA CLASS GLUTATHIONE TRANSFERASE FROM SQUID, A PROGENITOR OF THE LENS-CRYSTALLINS OF CEPHALOPODS== | ||
<StructureSection load='1gsq' size='340' side='right'caption='[[1gsq]], [[Resolution|resolution]] 2.40Å' scene=''> | |||
You may | == Structural highlights == | ||
<table><tr><td colspan='2'>[[1gsq]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Todarodes_pacificus Todarodes pacificus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GSQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1GSQ FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.4Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GDN:GLUTATHIONE+S-(2,4+DINITROBENZENE)'>GDN</scene></td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1gsq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1gsq OCA], [https://pdbe.org/1gsq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1gsq RCSB], [https://www.ebi.ac.uk/pdbsum/1gsq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1gsq ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/GST_NOTSL GST_NOTSL] High activity toward 1-chloro-2,4-dinitrobenzene. Not very efficient at catalyzing the addition of GSH to enones and epoxides.<ref>PMID:7727393</ref> | |||
== 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/gs/1gsq_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/main_output.php?pdb_ID=1gsq ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The glutathione transferase from squid digestive gland is unique in its very high catalytic activity toward 1-chloro-2,4-dinitrobenzene and in its ancestral relationship to the genes encoding the S-crystallins of the lens of cephalopod eye. The three-dimensional structure of this glutathione transferase in complex with the product 1-(S-glutathionyl)-2,4-dinitrobenzene (GSDNB) has been solved by multiple isomorphous replacement techniques at a resolution of 2.4 A. Like the cytosolic enzymes from vertebrates, the squid protein is a dimer. The structure is similar in overall topology to the vertebrate enzymes but has a dimer interface that is unique when compared to all of the vertebrate and invertebrate structures thus far reported. The active site of the enzyme is very open, a fact that appears to correlate with the high turnover number (800 s-1 at pH 6.5) toward 1-chloro-2,4-dinitrobenzene. Both kcat and kcat/KmCDNB exhibit pH dependencies consistent with a pKa for the thiol of enzyme-bound GSH of 6.3. The enzyme is not very efficient at catalyzing the addition of GSH to enones and epoxides. This particular characteristic appears to be due to the lack of an electrophilic residue at position 106, which is often found in other GSH transferases. The F106Y mutant enzyme is much improved in catalyzing these reactions. Comparisons of the primary structure, gene structure, and three-dimensional structure with class alpha, mu, and pi enzymes support placing the squid protein in a separate enzyme class, sigma. The unique dimer interface suggests that the class sigma enzyme diverged from the ancestral precursor prior to the divergence of the precursor gene for the alpha, mu, and pi classes. | |||
Three-dimensional structure, catalytic properties, and evolution of a sigma class glutathione transferase from squid, a progenitor of the lens S-crystallins of cephalopods.,Ji X, von Rosenvinge EC, Johnson WW, Tomarev SI, Piatigorsky J, Armstrong RN, Gilliland GL Biochemistry. 1995 Apr 25;34(16):5317-28. PMID:7727393<ref>PMID:7727393</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 1gsq" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Glutathione S-transferase 3D structures|Glutathione S-transferase 3D structures]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
== | [[Category: Large Structures]] | ||
[[Category: Todarodes pacificus]] | |||
[[Category: Armstrong RN]] | |||
== | [[Category: Gilliland GL]] | ||
[[Category: Ji X]] | |||
[[Category: | [[Category: Rosenvinge ECV]] | ||
[[Category: | |||
[[Category: Armstrong | |||
[[Category: Gilliland | |||
[[Category: Ji | |||
[[Category: Rosenvinge | |||
Latest revision as of 12:21, 30 August 2023
THREE-DIMENSIONAL STRUCTURE, CATALYTIC PROPERTIES AND EVOLUTION OF A SIGMA CLASS GLUTATHIONE TRANSFERASE FROM SQUID, A PROGENITOR OF THE LENS-CRYSTALLINS OF CEPHALOPODSTHREE-DIMENSIONAL STRUCTURE, CATALYTIC PROPERTIES AND EVOLUTION OF A SIGMA CLASS GLUTATHIONE TRANSFERASE FROM SQUID, A PROGENITOR OF THE LENS-CRYSTALLINS OF CEPHALOPODS
Structural highlights
FunctionGST_NOTSL High activity toward 1-chloro-2,4-dinitrobenzene. Not very efficient at catalyzing the addition of GSH to enones and epoxides.[1] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe glutathione transferase from squid digestive gland is unique in its very high catalytic activity toward 1-chloro-2,4-dinitrobenzene and in its ancestral relationship to the genes encoding the S-crystallins of the lens of cephalopod eye. The three-dimensional structure of this glutathione transferase in complex with the product 1-(S-glutathionyl)-2,4-dinitrobenzene (GSDNB) has been solved by multiple isomorphous replacement techniques at a resolution of 2.4 A. Like the cytosolic enzymes from vertebrates, the squid protein is a dimer. The structure is similar in overall topology to the vertebrate enzymes but has a dimer interface that is unique when compared to all of the vertebrate and invertebrate structures thus far reported. The active site of the enzyme is very open, a fact that appears to correlate with the high turnover number (800 s-1 at pH 6.5) toward 1-chloro-2,4-dinitrobenzene. Both kcat and kcat/KmCDNB exhibit pH dependencies consistent with a pKa for the thiol of enzyme-bound GSH of 6.3. The enzyme is not very efficient at catalyzing the addition of GSH to enones and epoxides. This particular characteristic appears to be due to the lack of an electrophilic residue at position 106, which is often found in other GSH transferases. The F106Y mutant enzyme is much improved in catalyzing these reactions. Comparisons of the primary structure, gene structure, and three-dimensional structure with class alpha, mu, and pi enzymes support placing the squid protein in a separate enzyme class, sigma. The unique dimer interface suggests that the class sigma enzyme diverged from the ancestral precursor prior to the divergence of the precursor gene for the alpha, mu, and pi classes. Three-dimensional structure, catalytic properties, and evolution of a sigma class glutathione transferase from squid, a progenitor of the lens S-crystallins of cephalopods.,Ji X, von Rosenvinge EC, Johnson WW, Tomarev SI, Piatigorsky J, Armstrong RN, Gilliland GL Biochemistry. 1995 Apr 25;34(16):5317-28. PMID:7727393[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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