View source for 9fcg


==Medicago truncatula 5'-ProFAR isomerase (HISN3) D57N mutant in complex with PrFAR==
<StructureSection load='9fcg' size='340' side='right'caption='[[9fcg]], [[Resolution|resolution]] 1.54&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9fcg]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Medicago_truncatula Medicago truncatula]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9FCG OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9FCG 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]] 1.54&#8491;</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=9fcg FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9fcg OCA], [https://pdbe.org/9fcg PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9fcg RCSB], [https://www.ebi.ac.uk/pdbsum/9fcg PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9fcg ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/G7IFI7_MEDTR G7IFI7_MEDTR] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Histidine biosynthesis is essential for the growth and development of plants, where it occurs within chloroplasts. The eleven reactions are catalyzed by eight enzymes, known as HISN1-8, each acting sequentially. Here, we present the crystal structures of a 5'-ProFAR isomerase (HISN3) from the model legume Medicago truncatula bound to its enzymatically synthesized substrate (ProFAR) and product (PrFAR). The active site of MtHISN3 contains a sodium cation that participates in ligand recognition, a feature not observed in bacterial and fungal structures of homologous enzymes. The steady-state kinetics of wild-type MtHISN3 revealed a slightly higher turnover rate compared to its bacterial homologs. Plant HISN3 sequences contain an unusually elongated Lys60-Ser91 fragment, while deletion of the 74-80 region resulted in a 30-fold loss in catalytic efficiency compared to the wild-type. Molecular dynamics simulations suggested that the fragment facilitates product release, thereby contributing to a higher k(cat). Moreover, conservation analyses suggested a non-cyanobacterial origin for plant HISN3 enzymes, which is another instance of a non-cyanobacterial enzyme in the plant histidine biosynthetic pathway. Finally, a virtual screening campaign yielded five molecules, with the energy gains ranging between -13.6 and -13.1 kcal/mol, which provide new scaffolds for the future development of herbicides.

Structural, kinetic, and evolutionary peculiarities of HISN3, a plant 5'-ProFAR isomerase.,Witek W, Imiolczyk B, Ruszkowski M Plant Physiol Biochem. 2024 Aug 22;215:109065. doi: 10.1016/j.plaphy.2024.109065. PMID:39186852<ref>PMID:39186852</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9fcg" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Medicago truncatula]]
[[Category: Imiolczyk B]]
[[Category: Ruszkowski M]]
[[Category: Witek W]]