1aha: Difference between revisions

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-[[Image:1aha.jpg|left|200px]]<br /><applet load="1aha" size="450" color="white" frame="true" align="right" spinBox="true"
-caption="1aha, resolution 2.2&Aring;" />
-'''THE N-GLYCOSIDASE MECHANISM OF RIBOSOME-INACTIVATING PROTEINS IMPLIED BY CRYSTAL STRUCTURES OF ALPHA-MOMORCHARIN'''<br />
-==Overview==
+==THE N-GLYCOSIDASE MECHANISM OF RIBOSOME-INACTIVATING PROTEINS IMPLIED BY CRYSTAL STRUCTURES OF ALPHA-MOMORCHARIN==
-BACKGROUND: alpha-Momorcharin (alpha MMC) is a type I, ribosome-inactivating protein. It inhibits protein synthesis by, hydrolytically removing a specific adenine residue from a highly, conserved, single-stranded loop of rRNA. RESULTS: Here we describe the, determination and refinement of the crystal structures of alpha MMC in the, native state and in complexes with the product, adenine, and a substrate, analogue, formycin 5'-monophosphate (FMP) at high resolution. Both adenine, and the base of FMP are tightly bound; the ribose of bound FMP adopts a, strained, high-energy conformation, which may mimic the structure of the, transition state. CONCLUSIONS: These structures indicate that residues, Tyr70, Glu160 and Arg163 of alpha MMC are the most critical for catalysis., We propose that the strained conformation of the ribose in the target, adenosine weakens the glycoside bond. Partial protonation mediated by, Arg163 then facilitates N-glycoside bond cleavage, leading to the, formation of an oxycarbonium ion intermediate which is stabilized by the, negatively-charged Glu160. Tyr70 adopts subtly different conformations in, the three structures implying that it may be important in substrate, recognition and perhaps catalysis.
+<StructureSection load='1aha' size='340' side='right'caption='[[1aha]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
+== Structural highlights ==
+<table><tr><td colspan='2'>[[1aha]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Momordica_charantia Momordica charantia]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1AHA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1AHA 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]] 2.2&#8491;</td></tr>
+<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ADE:ADENINE'>ADE</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=1aha FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1aha OCA], [https://pdbe.org/1aha PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1aha RCSB], [https://www.ebi.ac.uk/pdbsum/1aha PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1aha ProSAT]</span></td></tr>
+</table>
+== Function ==
+[https://www.uniprot.org/uniprot/RIP1_MOMCH RIP1_MOMCH]
+== 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/ah/1aha_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=1aha ConSurf].
+<div style="clear:both"></div>
-==About this Structure==
+==See Also==
-AHA is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Momordica_charantia Momordica charantia] with ADE as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/rRNA_N-glycosylase rRNA N-glycosylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.22 3.2.2.22] Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1AHA OCA].
+*[[Ribosome inactivating protein 3D structures|Ribosome inactivating protein 3D structures]]
+__TOC__
-==Reference==
+</StructureSection>
-The N-glycosidase mechanism of ribosome-inactivating proteins implied by crystal structures of alpha-momorcharin., Ren J, Wang Y, Dong Y, Stuart DI, Structure. 1994 Jan 15;2(1):7-16. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=8075985 8075985]
+[[Category: Large Structures]]
 [[Category: Momordica charantia]]
-[[Category: Single protein]]
+[[Category: Dong Y]]
-[[Category: rRNA N-glycosylase]]
+[[Category: Ren J]]
-[[Category: Dong, Y.]]
+[[Category: Stuart DI]]
-[[Category: Ren, J.]]
+[[Category: Wang Y]]
-[[Category: Stuart, D.I.]]
-[[Category: Wang, Y.]]
-[[Category: ADE]]
-[[Category: glycosidase]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 10:51:03 2007''