2mas: Difference between revisions
New page: left|200px<br /> <applet load="2mas" size="450" color="white" frame="true" align="right" spinBox="true" caption="2mas, resolution 2.3Å" /> '''PURINE NUCLEOSIDE HY... |
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== | ==PURINE NUCLEOSIDE HYDROLASE WITH A TRANSITION STATE INHIBITOR== | ||
Nucleoside N-ribohydrolases are targets for disruption of purine salvage | <StructureSection load='2mas' size='340' side='right'caption='[[2mas]], [[Resolution|resolution]] 2.30Å' scene=''> | ||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[2mas]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Crithidia_fasciculata Crithidia fasciculata]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2MAS OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2MAS 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]] 2.3Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=PIR:2-(4-AMINO-PHENYL)-5-HYDROXYMETHYL-PYRROLIDINE-3,4-DIOL'>PIR</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=2mas FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2mas OCA], [https://pdbe.org/2mas PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2mas RCSB], [https://www.ebi.ac.uk/pdbsum/2mas PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2mas ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/IUNH_CRIFA IUNH_CRIFA] Catalyzes the hydrolysis of all of the commonly occurring purine and pyrimidine nucleosides into ribose and the associated base, but has a preference for inosine and uridine as substrates. | |||
== 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/ma/2mas_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=2mas ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Nucleoside N-ribohydrolases are targets for disruption of purine salvage in the protozoan parasites. The structure of a trypanosomal N-ribohydrolase in complex with a transition-state inhibitor is reported at 2.3 A resolution. The nonspecific nucleoside hydrolase from Crithidia fasciculata cocrystallized with p-aminophenyliminoribitol reveals tightly bound Ca2+ as a catalytic site ligand. The complex with the transition-state inhibitor is characterized by (1) large protein conformational changes to create a hydrophobic leaving group site (2) C3'-exo geometry for the inhibitor, typical of a ribooxocarbenium ion (3) stabilization of the ribooxocarbenium analogue between the neighboring group 5'-hydroxyl and bidentate hydrogen bonds to Asn168; and (4) octacoordinate Ca2+ orients a catalytic site water and is liganded to two hydroxyls of the inhibitor. The mechanism is ribooxocarbenium stabilization with weak leaving group activation and is a departure from glucohydrolases which use paired carboxylates to achieve the transition state. | |||
Trypanosomal nucleoside hydrolase. A novel mechanism from the structure with a transition-state inhibitor.,Degano M, Almo SC, Sacchettini JC, Schramm VL Biochemistry. 1998 May 5;37(18):6277-85. PMID:9572842<ref>PMID:9572842</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 2mas" style="background-color:#fffaf0;"></div> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Crithidia fasciculata]] | [[Category: Crithidia fasciculata]] | ||
[[Category: | [[Category: Large Structures]] | ||
[[Category: Degano | [[Category: Degano M]] | ||
[[Category: Sacchettini | [[Category: Sacchettini JC]] | ||
[[Category: Schramm | [[Category: Schramm VL]] | ||