Structure of the Thiamine- and Flavin-Dependent Enzyme Pyruvate Oxidase

作者：Yves A. Muller, Georg E. Schulz · 发表于：Science · 年份：1993 · DOI：10.1126/science.8438155 · 被引用次数：234 · 研究领域：Biochemical Acid Research Studies、Amino Acid Enzymes and Metabolism、Alcoholism and Thiamine Deficiency

Pyruvate oxidase from Lactobacillus plantarum is a tetrameric enzyme that decarboxylates pyruvate, producing hydrogen peroxide and the energy-storage metabolite acetylphosphate. Structure determination at 2.1 angstroms showed that the cofactors thiamine pyrophosphate (TPP) and flavin adenine dinucleotide (FAD) are bound at the carboxyl termini of six-stranded parallel beta sheets. The pyrophosphate moiety of TPP is bound to a metal ion and to a beta alpha alpha beta unit corresponding to an established sequence fingerprint. The spatial arrangement of TPP and FAD suggests that the oxidation of the oxyethyl intermediate does not occur by hydride displacement but rather by a two-step transfer of two electrons.