Near-infrared light-driven asymmetric photolytic reduction of ketone using inorganic-enzyme hybrid biocatalyst

Effective photolytic regeneration of the NAD(P)H cofactor in enzymatic reductions is an important and elusive goal in biocatalysis. It can, in principle, be achieved using a near-infrared light (NIR) driven artificial photosynthesis system employing H₂O as the sacrificial reductant. To this end we utilized TiO₂/reduced...

Precision Engineering of the Co-immobilization of Enzymes for Cascade Biocatalysis

The design and orderly layered co-immobilization of multiple enzymes on resin particles remain challenging. In this study, the SpyTag/SpyCatcher binding pair was fused to the N-terminus of an alcohol dehydrogenase (ADH) and an aldo-keto reductase (AKR), respectively. A non-canonical amino acid (ncAA), p-azido-L-phenylalanine (p-AzF), as the...

Assessment of Vigilance Level during Work: Fitting a Hidden Markov Model to Heart Rate Variability

This study aimed to enhance the real-time performance and accuracy of vigilance assessment by developing a hidden Markov model (HMM). Electrocardiogram (ECG) signals were collected and processed to remove noise and baseline drift. A group of 20 volunteers participated in the study. Their heart rate variability (HRV) was measured to train...

Designing an enzyme assembly line for green cascade processes using bio-orthogonal chemistry

Two non-canonical amino acids (ncAAs) with bio-orthogonal reactive groups, namely, p-azido-l-phenylalanine (p-AzF) and p-propargyloxy-l-phenylalanine (p-PaF), were genetically inserted into an aldo-keto reductase (AKR) and an alcohol dehydrogenase (ADH), respectively, at two preselected sites for each enzyme. The variants were expressed in...

Engineering ketoreductases for the enantioselective synthesis of chiral alcohols

The use of engineered ketoreductases (KREDS), both as whole microbial cells and isolated enzymes, in the highly enantiospecific reduction of prochiral ketones is reviewed. The homochiral alcohol products are key intermediates in, for example, pharmaceuticals synthesis. The application of sophisticated protein engineering and enzyme...