   1.1.3.46 | synthesis |
whole-cell bioconversion of L-tyrosine into protocatechuic acid using artificial enzymatic cascades engineered in Escherichia coli. The first biocatalytic route comprises L-amino acid deaminase (LAAD) from Proteus mirabilis, hydroxymandelate synthase (HmaS) from Amycolatopsis orientalis, two-component flavin-dependent monooxygenase (HpaBC) from Escherichia coli, hydroxymandelate oxidase (HMO) from Streptomyces coelicolor, benzoylformate decarboxylase (BFD) from Pseudomonas putida, and aldehyde dehydrogenase (ALDH) from Saccharomyces cerevisiae. Combining LAAD/HmaS/HpaBC results in efficient synthesis of 3,4-dihydroxymandelate, which can be further converted to protocatechuic acid by HMO/BFD/ALDH to a final conversion of 64.4%. The recombinant E. coli catalyzes >99% conversion of L-tyrosine into 4-hydroxybenzoate within 12 h, further incorporation of 4-hydroxybenzoate hydroxylase PobA results in complete conversion of 4-hydroxybenzoate into protocatechuic acid, reaching >99% conversion |
762555 |
