Microbial production of the aromatic building‐blocks (S)‐styrene oxide and (R)‐1,2‐phenylethanediol from renewable resources

摘要: (S)-Styrene oxide and (R)-1,2-phenylethanediol are chiral aromatic molecular building blocks used commonly as precursors to pharmaceuticals other specialty chemicals. Two pathways have been engineered in Escherichia coli for their individual biosynthesis directly from glucose. The novel each constitute extensions of the previously styrene pathway, developed by co-expressing either monooxygenase (SMO) or dioxygenase (SDO) convert (S)-styrene (R)-1,2-phenylethanediol, respectively. StyAB Pseudomonas putida S12 was determined be most effective SMO. SDO activity achieved using NahAaAbAcAd sp. NCIB 9816-4, a naphthalene with known broad substrate specificity. Production phenylalanine, precursor both pathways, systematically enhanced through number mutations, notably via deletion tyrA over-expression tktA. As result, reached titers high 1.23 g/L, at 1.32 g/L already approach toxicity limit. aromatics, product strongly correlated model membrane accumulation disruption. This study additionally demonstrates that greater flux pathway can if its is addressed, this case reacting less toxic products.