PYRUVATE OXIDASE MUTANTS AND PROCESS FOR THE PREPARATION THEREOF

摘要

A pyruvate oxidase which decarboxylates pyruvate with the formation of hydrogen peroxide and is active without the addition of FAD, thiamine pyrophosphate and divalent metal ions, wherein, in the amino acid sequence, it contains at least one exchange of proline in position 178 and/or of alanine in position 425, and a process for its preparation; the enzyme is employed in the quantitative determination of pyruvate and pyruvate-forming enzymes and their substrates; in particular the enzyme has increased stability towards salts and in the alkaline pH range.