1dxe: Difference between revisions

[[Image:1dxe.gif|left|200px]]<br /><applet load="1dxe" size="350" color="white" frame="true" align="right" spinBox="true"  

Carbon-carbon bond formation is an essential reaction in organic chemistry and the use of aldolase enzymes for the stereochemical control of such reactions is an attractive alternative to conventional chemical methods. Here we describe the crystal structures of a novel class II enzyme, 2-dehydro-3-deoxy-galactarate (DDG) aldolase from Escherichia coli, in the presence and absence of substrate. The crystal structure was determined by locating only four Se sites to obtain phases for 506 protein residues. The protomer displays a modified (alpha/beta)(8) barrel fold, in which the eighth alpha-helix points away from the beta-barrel instead of packing against it. Analysis of the DDG aldolase crystal structures suggests a novel aldolase mechanism in which a phosphate anion accepts the proton from the methyl group of pyruvate.

1DXE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=PO4:'>PO4</scene> and <scene name='pdbligand=MG:'>MG</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/2-dehydro-3-deoxyglucarate_aldolase 2-dehydro-3-deoxyglucarate aldolase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.2.20 4.1.2.20] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DXE OCA].  

[[Category: Blackwell, N C.]]

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