53369-07-6Relevant articles and documents
Tuning amino acid dehydrogenases with featured sequences for L-phosphinothricin synthesis by reductive amination
Cheng, Feng,Li, Heng,Li, Qing-Hua,Xie, Dong,Xue, Ya-Ping,Zhang, Kai,Zheng, Yu-Guo
, p. 35 - 43 (2020)
Biosynthesizing unnatural chiral amino acids is challenging due to the limited reductive amination activity of amino acid dehydrogenase (AADH). Here, for the asymmetric synthesis of L-phosphinothricin from 2-oxo-4-[(hydroxy)(methyl)phosphinoyl]butyric acid (PPO), a glutamate dehydrogenase gene (named GluDH3) from Pseudomonas monteilii was selected, cloned and expressed in Escherichia coli (E. coli). To boost its activity, a “two-step”-based computational approach was developed and applied to select the potential beneficial amino acid positions on GluDH3. L-phosphinothricin was synthesized by GluDH-catalyzed asymmetric amination using the D-glucose dehydrogenase from Exiguobacterium sibiricum (EsGDH) for NADPH regeneration. Using lyophilized E. coli cells that co-expressed GluDH3_V375S and EsGDH, up to 89.04 g L?1 PPO loading was completely converted to L-phosphinothricin within 30 min at 35 °C with a space-time yield of up to 4.752 kg·L?1·d?1. The beneficial substitution V375S with increased polar interactions between K90, T193, and substrate PPO exhibited 168.2-fold improved catalytic efficiency (kcat/KM) and 344.8-fold enhanced specific activity. After the introduction of serine residues into other GluDHs at specific positions, forty engineered GluDHs exhibited the catalytic functions of “glufosinate dehydrogenase” towards PPO.
A Single-Transaminase-Catalyzed Biocatalytic Cascade for Efficient Asymmetric Synthesis of l-Phosphinothricin
Cheng, Feng,Li, Ju-Mou,Zhou, Shi-Peng,Liu, Qi,Jin, Li-Qun,Xue, Ya-Ping,Zheng, Yu-Guo
, p. 345 - 348 (2020/10/02)
A single-transaminase-catalyzed biocatalytic cascade was developed by employing the desired biocatalyst, ATA-117-Rd11, that showed high activity toward 2-oxo-4-[(hydroxy)(methyl)phosphinoyl] butyric acid (PPO) and α-ketoglutarate, and low activity against pyruvate. The cascade successfully promotes a highly asymmetric amination reaction for the synthesis of l-phosphinothricin (l-PPT) with high conversion (>95 %) and>99 % ee. In a scale-up experiment, using 10 kg pre-frozen E. coli cells harboring ATA-117-Rd11 as catalyst, 80 kg PPO was converted to ≈70 kg l-PPT after 24 hours with a high ee value (>99 %).
Development of a biocatalytic cascade for synthesis of 2-oxo-4-(hydroxymethylphosphinyl) butyric acid in one pot
Xu, Jianmiao,Zhang, Kai,Cao, Huiting,Li, Heng,Cheng, Feng,Cao, Chenghao,Xue, Ya-Ping,Zheng, Yu-Guo
, p. 190 - 197 (2020/07/30)
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.
