View source for 6loq


==crystal structure of alpha-momorcharin in complex with cAMP==
<StructureSection load='6loq' size='340' side='right'caption='[[6loq]], [[Resolution|resolution]] 1.33&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6loq]] 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=6LOQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6LOQ 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]] 1.331&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CMP:ADENOSINE-3,5-CYCLIC-MONOPHOSPHATE'>CMP</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=6loq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6loq OCA], [https://pdbe.org/6loq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6loq RCSB], [https://www.ebi.ac.uk/pdbsum/6loq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6loq ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RIP1_MOMCH RIP1_MOMCH] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Alpha-momorcharin (Alpha-MMC) from the seed of bitter melon is a type I ribosome inactivating protein (RIP) that removes a specific adenine from 28S rRNA and inhibits protein biosynthesis. Here, we report seven crystal complex structures of alpha-MMC with different substrate analogs (adenine, AMP, cAMP, dAMP, ADP, GMP, and xanthosine) at 1.08 A to 1.52 A resolution. These structures reveal that not only adenine, but also guanine and their analogs can effectively bind to alpha-MMC. The side chain of Tyr93 adopts two conformations, serving as a switch to open and close the substrate binding pocket of alpha-MMC. Although adenine, AMP, GMP, and guanine are located in a similar active site in different RIPs, residues involved in the interaction between RIPs and substrate analogs are slightly different. Complex structures of alpha-MMC with different substrate analogs solved in this study provide useful information on its enzymatic mechanisms and may enable the development of new inhibitors to treat the poisoning of alpha-MMC.

Atomic-resolution structures of type I ribosome inactivating protein alpha-momorcharin with different substrate analogs.,Fan X, Wang Y, Guo F, Zhang Y, Jin T Int J Biol Macromol. 2020 Dec 1;164:265-276. doi: 10.1016/j.ijbiomac.2020.07.063., Epub 2020 Jul 10. PMID:32653369<ref>PMID:32653369</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6loq" style="background-color:#fffaf0;"></div>

==See Also==
*[[Ribosome inactivating protein 3D structures|Ribosome inactivating protein 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Momordica charantia]]
[[Category: Fan X]]
[[Category: Jin T]]