Chiral phenylglycinol is a very important chemical in the pharmaceutical manufacturing. Current methods for synthesis of chiral phenylglycinol often suffered from unsatisfied selectivity, low product yield and using the non-renewable resourced substrates, then the synthesis of chiral phenylglycinol remain a grand challenge. Design and construction of synthetic microbial consortia is a promising strategy to convert bio-based materials to high value-added chiral compounds. In this study, we reported a six-step artificial cascade biocatalysis system for conversion of biobased L-phenylalanine to yield chiral phenylglycinol. The cascade biocatalysis system was conducted by a microbial consortium composed of two engineered recombinant Escherichia coli cells modules, one recombinant E. coli cell module co-expression of six different enzymes (phenylalanine ammonia lyase/ferulic acid decarboxylase/phenylacrylic acid decarboxylase/styrene monooxygenase/epoxide hydrolase/alcohol dehydrogenase) for efficient conversion of L-phenylalanine into 2-hydroxyacetophenone. The second recombinant E. coli cell module expression of an (R)-ω-transaminase or co-expression of the (S)-ω-transaminase, alanine dehydrogenase and glucose dehydrogenase for conversion of 2-hydroxyacetophenone to (S)- or (R)-phenylglycinol, respectively. Combining the two engineered E. coli cell modules, after the optimization of bioconversion conditions (including pH, temperature, glucose concentration, amine donor concentration and cell ratio), L-phenylalanine could be easily converted to (R)-phenylglycinol and (S)-phenylglycinol with up to 99% conversion and >99% ee. Preparative scale biotransformation was also conducted on 100 mL scale, (S)-phenylglycinol and (R)-phenylglycinol were obtained in 71.0% and 80.5% yield, >99% ee, and 5.19 g/L.d and 4.42 g/L.d productivity, respectively. The salient features of this biocatalytic cascade system are good yields, excellent ee, mild reaction conditions and no need for additional cofactor (NADH/NAD+), provide a practical biocatalytic method for sustainable synthesis of (S)-phenylglycinol and (R)-phenylglycinol from biobased L-phenylalanine.

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