6dvs: Difference between revisions

<StructureSection load='6dvs' size='340' side='right' caption='[[6dvs]], [[Resolution|resolution]] 1.82&Aring;' scene=''>

<table><tr><td colspan='2'>[[6dvs]] is a 1 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6DVS OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6DVS FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=TRS:2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL'>TRS</scene></td></tr>

<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/D-4-hydroxyphenylglycine_transaminase D-4-hydroxyphenylglycine transaminase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.6.1.72 2.6.1.72] </span></td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6dvs FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6dvs OCA], [http://pdbe.org/6dvs PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6dvs RCSB], [http://www.ebi.ac.uk/pdbsum/6dvs PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6dvs ProSAT]</span></td></tr>

== Publication Abstract from PubMed ==

Aromatic d-amino acids are key precursors for the production of many small molecule therapeutics. Therefore, the development of biocatalytic methods for their synthesis is of great interest. An enzyme that has great potential as a biocatalyst for the synthesis of d-amino acids is the stereoinverting d-phenylglycine aminotransferase (DPAT) from Pseudomonas stutzeri ST-201. This enzyme catalyzes a unique l to d transamination reaction that produces d-phenylglycine and alpha-ketoglutarate from benzoylformate and l-glutamate, via a mechanism that is poorly understood. Here, we present the crystal structure of DPAT, which shows that the enzyme folds into a two-domain structure representative of class III aminotransferases. Guided by the crystal structure, we performed saturation mutagenesis to probe the substrate binding pockets of the enzyme. These experiments helped us identify two arginine residues (R34 and R407), one in each binding pocket, that are essential to catalysis. Together with kinetic analyses using a library of amino acid substrates, our mutagenesis and structural studies allow us to propose a binding model that explains the dual l/d specificity of DPAT. Our kinetic analyses also demonstrate that DPAT can catalyze the transamination of beta- and gamma-amino acids, reclassifying this enzyme as an omega-aminotransferase. Collectively, our studies highlight that the DPAT active site is amenable to protein engineering for expansion of its substrate scope, which offers the opportunity to generate new biocatalysts for the synthesis of a variety of valuable optically pure d-amino acids from inexpensive and abundant l-amino acids.

 

<div class="pdbe-citations 6dvs" style="background-color:#fffaf0;"></div>

== References ==

[[Category: D-4-hydroxyphenylglycine transaminase]]

[[Category: Chica, R]]

[[Category: Couture, J F]]

[[Category: Aminotransferase]]

[[Category: Transferase]]