View source for 3vsc


==Crystal Structure of the K127A Mutant of O-Phosphoserine Sulfhydrylase Complexed with External Schiff Base of Pyridoxal 5'-Phosphate with O-Phospho-L-Serine==
<StructureSection load='3vsc' size='340' side='right'caption='[[3vsc]], [[Resolution|resolution]] 2.07&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3vsc]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Aeropyrum_pernix_K1 Aeropyrum pernix K1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3VSC OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3VSC 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]] 2.07&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MPD:(4S)-2-METHYL-2,4-PENTANEDIOL'>MPD</scene>, <scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene>, <scene name='pdbligand=SEP:PHOSPHOSERINE'>SEP</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=3vsc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3vsc OCA], [https://pdbe.org/3vsc PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3vsc RCSB], [https://www.ebi.ac.uk/pdbsum/3vsc PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3vsc ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CYSO_AERPE CYSO_AERPE] Cysteine synthase that can also catalyze the synthesis of S-sulfo-L-cysteine from thiosulfate and O(3)-acetyl-L-serine, as well as the sulfhydrylation of L-serine by sulfide.<ref>PMID:12644499</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
L-Cysteine is synthesized from O-acetyl-L-serine (OAS) and sulfide by O-acetylserine sulfhydrylase (OASS; EC 2.5.1.47) in plants and bacteria. O-phosphoserine sulfhydrylase (OPSS; EC 2.5.1.65) is a novel enzyme from the hyperthermophilic aerobic archaeon Aeropyrum pernix K1 (2003). OPSS can use OAS or O-phospho-L-serine (OPS) to synthesize L-cysteine. To elucidate the mechanism of the substrate specificity of OPSS, we analyzed three-dimensional structures of the active site of the enzyme. The active-site lysine (K127) of OPSS forms an internal Schiff base with pyridoxal 5'-phosphate. Therefore, crystals of the complexes formed by the K127A mutant with the external Schiff base of pyridoxal 5'-phosphate with either OPS or OAS were prepared and examined by X-ray diffraction analysis. In contrast to that observed for OASS, no significant difference was seen in the overall structure between the free and complexed forms of OPSS. The side chains of T152, S153, and Q224 interacted with the carboxylate of the substrates, as a previous study has suggested. The side chain of R297 has been proposed to recognize the phosphate group of OPS. Surprisingly, however, the position of R297 was significantly unchanged in the complex of the OPSS K127A mutant with the external Schiff base, allowing enough space for an interaction with OPS. The positively charged environment around the entrance of the active site including S153 and R297 is important for accepting negatively charged substrates such as OPS.

Structural analysis of the substrate recognition mechanism in O-phosphoserine sulfhydrylase from the hyperthermophilic archaeon Aeropyrum pernix K1.,Nakamura T, Kawai Y, Kunimoto K, Iwasaki Y, Nishii K, Kataoka M, Ishikawa K J Mol Biol. 2012 Sep 7;422(1):33-44. Epub 2012 May 11. PMID:22580223<ref>PMID:22580223</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 3vsc" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Aeropyrum pernix K1]]
[[Category: Large Structures]]
[[Category: Ishikawa K]]
[[Category: Kataoka M]]
[[Category: Kawai Y]]
[[Category: Nakamura T]]