Development of a biocatalytic cascade for synthesis of 2-oxo-4-(hydroxymethylphosphinyl) butyric acid in one pot

2-Oxo-4-(hydroxymethylphosphinyl) butyric acid (PPO) is an important precursor compound for the broad-spectrum herbicide l-glufosinate (L-PPT). In this study, the gene of d-amino acid oxidase (DAAO) was cloned and expressed in Escherichia coli. By coupling exogenous catalase (CAT), a biocatalytic cascade was constructed for synthesis of PPO in one pot. The bioprocess was optimized on a 300 mL scale reaction by one factor at a time optimization. The conversion of this biocatalytic cascade achieved 46.8% towards 400 mM DL-PPT within 4 h. These results indicated that DAAO could be applied to the large-scale bioproduction of PPO and provide a promising route for the asymmetric synthesis of L-PPT by bio-enzymatic methods using PPO as the substrate.