View source for 5wxy


==Crystal structure of Microcystis aeruginosa PCC 7806 aspartate racemase in complex with L-aspartate==
<StructureSection load='5wxy' size='340' side='right'caption='[[5wxy]], [[Resolution|resolution]] 2.63&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5wxy]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Microcystis_aeruginosa_PCC_7806 Microcystis aeruginosa PCC 7806]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5WXY OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5WXY 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]] 2.63&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ASP:ASPARTIC+ACID'>ASP</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=5wxy FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5wxy OCA], [https://pdbe.org/5wxy PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5wxy RCSB], [https://www.ebi.ac.uk/pdbsum/5wxy PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5wxy ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q9RNB4_MICAE Q9RNB4_MICAE] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
L-amino acids represent the most common amino acid form, most notably as protein residues, whereas D-amino acids, despite their rare occurrence, play significant roles in many biological processes. Amino acid racemases are enzymes that catalyze the interconversion of L- and/or D-amino acids. McyF is a pyridoxal 5'-phosphate (PLP) independent amino acid racemase that produces the substrate D-aspartate for the biosynthesis of microcystin in the cyanobacterium Microcystis aeruginosa PCC7806. Here we report the crystal structures of McyF in complex with citrate, L-Asp and D-Asp at 2.35, 2.63 and 2.80A, respectively. Structural analyses indicate that McyF and homologs possess highly conserved residues involved in substrate binding and catalysis. In addition, residues Cys87 and Cys195 were clearly assigned to the key catalytic residues of "two bases" that deprotonate D-Asp and L-Asp in a reaction independent of PLP. Further site-directed mutagenesis combined with enzymatic assays revealed that Glu197 also participates in the catalytic reaction. In addition, activity assays proved that McyF could also catalyze the interconversion of L-MeAsp between D-MeAsp, the precursor of another microcystin isoform. These findings provide structural insights into the catalytic mechanism of aspartate racemase and microcystin biosynthesis.

Structural insights into the catalysis and substrate specificity of cyanobacterial aspartate racemase McyF.,Cao DD, Zhang CP, Zhou K, Jiang YL, Tan XF, Xie J, Ren YM, Chen Y, Zhou CZ, Hou WT Biochem Biophys Res Commun. 2019 Jul 5;514(4):1108-1114. doi:, 10.1016/j.bbrc.2019.05.063. Epub 2019 May 14. PMID:31101340<ref>PMID:31101340</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5wxy" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Microcystis aeruginosa PCC 7806]]
[[Category: Cao DD]]
[[Category: Jiang YL]]
[[Category: Zhou CZ]]
[[Category: Zhou K]]