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spinqualitylabelsall models PDB ID 2ez8 Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image
, resolution 1.963Å
Ligands:	, , , and
Gene:	pox5 (Lactobacillus plantarum)
Activity:	Pyruvate oxidase, with EC number 1.2.3.3
Coordinates:	save as pdb, mmCIF, xml

Pyruvate oxidase variant F479W in complex with reaction intermediate 2-lactyl-thiamin diphosphate

Overview

Enzymes that use the cofactor thiamin diphosphate (ThDP, 1), the biologically active form of vitamin B(1), are involved in numerous metabolic pathways in all organisms. Although a theory of the cofactor's underlying reaction mechanism has been established over the last five decades, the three-dimensional structures of most major reaction intermediates of ThDP enzymes have remained elusive. Here, we report the X-ray structures of key intermediates in the oxidative decarboxylation of pyruvate, a central reaction in carbon metabolism catalyzed by the ThDP- and flavin-dependent enzyme pyruvate oxidase (POX)3 from Lactobacillus plantarum. The structures of 2-lactyl-ThDP (LThDP, 2) and its stable phosphonate analog, of 2-hydroxyethyl-ThDP (HEThDP, 3) enamine and of 2-acetyl-ThDP (AcThDP, 4; all shown bound to the enzyme's active site) provide profound insights into the chemical mechanisms and the stereochemical course of thiamin catalysis. These snapshots also suggest a mechanism for a phosphate-linked acyl transfer coupled to electron transfer in a radical reaction of pyruvate oxidase.

About this Structure

2EZ8 is a Single protein structure of sequence from Lactobacillus plantarum. Full crystallographic information is available from OCA.

Reference

The catalytic cycle of a thiamin diphosphate enzyme examined by cryocrystallography., Wille G, Meyer D, Steinmetz A, Hinze E, Golbik R, Tittmann K, Nat Chem Biol. 2006 Jun;2(6):324-8. Epub 2006 May 7. PMID:16680160

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