3vbe: Difference between revisions
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[[ | ==Crystal structure of beta-cyanoalanine synthase in soybean== | ||
<StructureSection load='3vbe' size='340' side='right' caption='[[3vbe]], [[Resolution|resolution]] 2.50Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[3vbe]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Glycine_max Glycine max]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3VBE OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3VBE FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene><br> | |||
<tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3vc3|3vc3]]</td></tr> | |||
<tr><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">GLYMA09G39390, OAS-TL3 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=3847 Glycine max])</td></tr> | |||
<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Cysteine_synthase Cysteine synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.5.1.47 2.5.1.47] </span></td></tr> | |||
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3vbe FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3vbe OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3vbe RCSB], [http://www.ebi.ac.uk/pdbsum/3vbe PDBsum]</span></td></tr> | |||
<table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Plants produce cyanide (CN(-)) during ethylene biosynthesis in the mitochondria and require beta-cyanoalanine synthase (CAS) for CN(-) detoxification. Recent studies show that CAS is a member of the beta-substituted alanine synthase (BSAS) family, which also includes the Cys biosynthesis enzyme O-acetylserine sulfhydrylase (OASS), but how the BSAS evolved distinct metabolic functions is not understood. Here we show that soybean (Glycine max) CAS and OASS form alpha-aminoacrylate reaction intermediates from Cys and O-acetylserine, respectively. To understand the molecular evolution of CAS and OASS in the BSAS enzyme family, the crystal structures of Gm-CAS and the Gm-CAS K95A mutant with a linked pyridoxal phosphate (PLP)-Cys molecule in the active site were determined. These structures establish a common fold for the plant BSAS family and reveal a substrate-induced conformational change that encloses the active site for catalysis. Comparison of CAS and OASS identified residues that covary in the PLP binding site. The Gm-OASS T81M, S181M, and T185S mutants altered the ratio of OASS:CAS activity but did not convert substrate preference to that of a CAS. Generation of a triple mutant Gm-OASS successfully switched reaction chemistry to that of a CAS. This study provides new molecular insight into the evolution of diverse enzyme functions across the BSAS family in plants. | |||
Structure of Soybean beta-Cyanoalanine Synthase and the Molecular Basis for Cyanide Detoxification in Plants.,Yi H, Juergens M, Jez JM Plant Cell. 2012 Jun;24(6):2696-706. Epub 2012 Jun 26. PMID:22739827<ref>PMID:22739827</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
== References == | |||
<references/> | |||
== | __TOC__ | ||
</StructureSection> | |||
[[Category: Cysteine synthase]] | [[Category: Cysteine synthase]] | ||
[[Category: Glycine max]] | [[Category: Glycine max]] | ||
Revision as of 13:26, 16 June 2014
Crystal structure of beta-cyanoalanine synthase in soybeanCrystal structure of beta-cyanoalanine synthase in soybean
Structural highlights
Publication Abstract from PubMedPlants produce cyanide (CN(-)) during ethylene biosynthesis in the mitochondria and require beta-cyanoalanine synthase (CAS) for CN(-) detoxification. Recent studies show that CAS is a member of the beta-substituted alanine synthase (BSAS) family, which also includes the Cys biosynthesis enzyme O-acetylserine sulfhydrylase (OASS), but how the BSAS evolved distinct metabolic functions is not understood. Here we show that soybean (Glycine max) CAS and OASS form alpha-aminoacrylate reaction intermediates from Cys and O-acetylserine, respectively. To understand the molecular evolution of CAS and OASS in the BSAS enzyme family, the crystal structures of Gm-CAS and the Gm-CAS K95A mutant with a linked pyridoxal phosphate (PLP)-Cys molecule in the active site were determined. These structures establish a common fold for the plant BSAS family and reveal a substrate-induced conformational change that encloses the active site for catalysis. Comparison of CAS and OASS identified residues that covary in the PLP binding site. The Gm-OASS T81M, S181M, and T185S mutants altered the ratio of OASS:CAS activity but did not convert substrate preference to that of a CAS. Generation of a triple mutant Gm-OASS successfully switched reaction chemistry to that of a CAS. This study provides new molecular insight into the evolution of diverse enzyme functions across the BSAS family in plants. Structure of Soybean beta-Cyanoalanine Synthase and the Molecular Basis for Cyanide Detoxification in Plants.,Yi H, Juergens M, Jez JM Plant Cell. 2012 Jun;24(6):2696-706. Epub 2012 Jun 26. PMID:22739827[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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