View source for 6xwl


==Cystathionine beta-synthase from Toxoplasma gondii==
<StructureSection load='6xwl' size='340' side='right'caption='[[6xwl]], [[Resolution|resolution]] 3.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6xwl]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Toxoplasma_gondii_ME49 Toxoplasma gondii ME49]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6XWL OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6XWL 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]] 3.201&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</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=6xwl FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6xwl OCA], [https://pdbe.org/6xwl PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6xwl RCSB], [https://www.ebi.ac.uk/pdbsum/6xwl PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6xwl ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A0A125YSJ9_TOXGM A0A125YSJ9_TOXGM] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Cysteine plays a major role in the redox homeostasis and antioxidative defense mechanisms of many parasites of the phylum Apicomplexa. Of relevance to human health is Toxoplasma gondii, the causative agent of toxoplasmosis. A major route of cysteine biosynthesis in this parasite is the reverse transsulfuration pathway involving two key enzymes cystathionine beta-synthase (CBS) and cystathionine gamma-lyase (CGL). CBS from T. gondii (TgCBS) catalyzes the pyridoxal-5-phosphate-dependent condensation of homocysteine with either serine or O-acetylserine to produce cystathionine. The enzyme can perform alternative reactions that use homocysteine and cysteine as substrates leading to the endogenous biosynthesis of hydrogen sulfide, another key element in maintaining the intracellular redox equilibrium. In contrast with human CBS, TgCBS lacks the N-terminal heme binding domain and is not responsive to S-adenosylmethionine. Herein, we describe the structure of a TgCBS construct that lacks amino acid residues 466-491 and shows the same activity of the native protein. TgCBS Delta466-491 was determined alone and in complex with reaction intermediates. A complementary molecular dynamics analysis revealed a unique domain organization, similar to the pathogenic mutant D444N of human CBS. Our data provides one missing piece in the structural diversity of CBSs by revealing the so far unknown three-dimensional arrangement of the CBS-type of Apicomplexa. This domain distribution is also detected in yeast and bacteria like Pseudomonas aeruginosa. These results pave the way for understanding the mechanisms by which TgCBS regulates the intracellular redox of the parasite, and have far-reaching consequences for the functional understanding of CBSs with similar domain distribution.

Structural insight into the unique conformation of cystathionine beta-synthase from Toxoplasma gondii.,Fernandez-Rodriguez C, Oyenarte I, Conter C, Gonzalez-Recio I, Nunez-Franco R, Gil-Pitarch C, Quintana I, Jimenez-Oses G, Dominici P, Martinez-Chantar ML, Astegno A, Martinez-Cruz LA Comput Struct Biotechnol J. 2021 Jun 6;19:3542-3555. doi:, 10.1016/j.csbj.2021.05.052. eCollection 2021. PMID:34194677<ref>PMID:34194677</ref>

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

==See Also==
*[[Cystathionine ÃÂ²-synthase 3D structures|Cystathionine ÃÂ²-synthase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Toxoplasma gondii ME49]]
[[Category: Astegno A]]
[[Category: Conter C]]
[[Category: Fernandez-Rodriguez C]]
[[Category: Gonzalez-Recio I]]
[[Category: Martinez-Chantar M]]
[[Category: Martinez-Cruz LA]]
[[Category: Oyenarte I]]
[[Category: Quintana I]]