The biocatalytic oxidative deamination of β-amino alcohols holds significant practical potential in kinetic resolution and/or deracemization process to access (R)-β-amino alcohols. This study exemplifies a notable instance of acquisition and utilization of this valuable oxidative deamination activity. Initially, the mutation N261M (M0) was identified to endow a native valine dehydrogenase with oxidative deamination activity toward a few (S)-β-amino alcohols. Subsequently, a phylogenetic analysis-guided, double-code saturation mutagenesis strategy was proposed to engineer M0's side-chain binding site. This strategy facilitated the substrate-specific evolution of M0, resulting in the creation of a panel of mutants (M1-M4) with noteworthy oxidative deamination activity toward structurally diverse (S)-β-amino alcohols. Using these engineered amine dehydrogenases, termed as β-amino alcohol dehydrogenases (β-AADHs), the complete kinetic resolution and even deracemization of a range of β-amino alcohols have been achieved. This work reports distinct biocatalysts and a synthetic strategy for the synthesis of enantiopure (R)-β-amino alcohols and offers an innovative approach for substrate-specificity engineering of enzymes.

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High resolution numerical weather models have recently raised a great interest in the InSAR community for atmospheric phase screen (APS) mitigation. Following the research carried out in [1], in this study we focus on investigating the sensitivity of WRF (Weather Research and Forecasting) predictions to the model parameter settings which may substantially affect the result of water vapor modeling and to different boundary conditions. We validate the model predictions using atmosphere-only interferograms as well as radiosonde records. Our result shows that the radiosonde records (on average) agree very well with the WRF predictions based on our new model settings. However, in terms of spatio-temporal delay variation, the new settings do not always lead to a better prediction and the correction of atmospheric delay is case dependent. Therefore, we conclude that WRF lacks the reliability to correct the realistic APS in interferograms.@en