A novel ‘parallel anti-sense’ cascade, employing aldehyde reductase and ω-transaminase, has been reported to produce bioplastic monomers with excellent conversion.

α,ω-Diols are important monomers widely used for the production of polyesters and polyurethanes. Here, biosynthesis of α,ω-diols (C 8-C 16) from renewable free fatty acids using CYP153A monooxygenase, carboxylic acid reductase, and E. coli endogenous aldehyde reductases is reported. The highest yield of α,ω-diol was achieved for the production of 1,12-dodecanediol. In the nicotinamide adenine dinucleotide phosphate (NADPH) cofactor regeneration system, 5 g/L of 1,12-dodecanediol was synthesized in 24 h reaction from the commercial ω-hydroxy dodecanoic acid. Finally, 1.4 g/L 1,12-dodecanediol was produced in a consecutive approach from dodecanoic acids. The results of this study demonstrated the scope of the potential development of bioprocesses to substitute the petroleum-based products in the polymer industry.

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A one‐pot deracemization strategy for α‐chiral amines is reported involving an enantioselective deamination to the corresponding ketone followed by a stereoselective amination by enantiocomplementary biocatalysts. Notably, this cascade employing a ω‐transaminase and amine dehydrogenase enabled the access to both (R)‐and (S)‐amine products, just by controlling the directions of the reactions catalyzed by them. A wide range of (R)‐and (S)‐amines was obtained with excellent conversions (>80 %) and enantiomeric excess (>99 % ee). Finally, preparative scale syntheses led to obtain enantiopure (R)‐ and (S)‐13 with the isolated yields of 53 and 75 %, respectively.

We report a highly atom‐efficient integrated cofactor/co‐product recycling cascade employing cycloalkylamines as multifaceted starting materials for the synthesis of nylon building blocks. Reactions using E. coli whole cells as well as purified enzymes produced excellent conversions ranging from >80 and 95 % into desired ω‐amino acids, respectively with varying substrate concentrations. The applicability of this tandem biocatalytic cascade was demonstrated to produce the corresponding lactams by employing engineered biocatalysts. For instance, ϵ‐caprolactam, a valuable polymer building block was synthesized with 75 % conversion from 10 mM cyclohexylamine by employing whole‐cell biocatalysts. This cascade could be an alternative for bio‐based production of ω‐amino acids and corresponding lactam compounds.

Amine dehydrogenase (AmDH) possesses tremendous potential for the synthesis of chiral amines because AmDH catalyzes the asymmetric reductive amination of ketone with high enatioselectivity. Although a reductive application of AmDH is favored in practice, the oxidative route is interesting as well for the preparation of chiral amines. Here, the kinetic resolution of racemic amines using AmDH was first extensively studied, and the AmDH reaction was combined with an NADH oxidase (Nox) to regenerate NAD + and to drive the reaction forward. When the kinetic resolution was carried out with 10 mM rac-2-aminoheptane and 5 mM rac-α-methylbenzylamine (α-MBA) using purified enzymes, the enantiomeric excess (ee) values were less than 26% due to the product inhibition of AmDH by ketone and the inhibition of Nox by the substrate amine. The use of a whole-cell biocatalyst co-expressing AmDH and Nox apparently reduces the substrate and product inhibition, and/or it increases the stability of the enzymes. Fifty millimoles (50 mM) rac-2-aminoheptane and 20 mM rac-α-MBA were successfully resolved into the (S)-form with >99% ee using whole cells. The present study demonstrates the potential of a whole-cell biocatalyst co-expressing AmDH and Nox for the kinetic resolution of racemic amines.

ω-Aminododecanoic acid is considered as one of the potential monomers of Nylon 12, a high-performance member of the bioplastic family. The biosynthesis of ω-aminododecanoic acid from renewable sources is an attractive process in the polymer industry. Here, we constructed three artificial self-sufficient P450s (ArtssP450s) using CYP153A13 from Alcanivorax borkumensis and cytochrome P450 reductase (CPR) domains of natural self-sufficient P450s (CYP102A1, CYP102A5, and 102D1). Among them, artificial self-sufficient P450 (CYP153A13BM3CPR) with CYP102A1 CPR showed the highest catalytically activity for dodecanoic acid (DDA) substrate. This form of ArtssP450 was further co-expressed with ω-TA from Silicobacter pomeroyi and AlkJ from Pseudomonas putida GPo1. This single-cell system was used for the biotransformation of dodecanoic acid (DDA) to ω-aminododecanoic acid (ω-AmDDA), wherein we could successfully biosynthesize 1.48 mM ω-AmDDA from 10 mM DDA substrate in a one-pot reaction. The productivity achieved in the present study was five times higher than that achieved in our previously reported multistep biosynthesis method (0.3 mM).

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