Fig. 2

Tyrosol production with plasmid-based expression of tyrA_Ec^fbr and ARO10_Sc in strain C. glutamicum AROM3 and derived deletion strains. A Tyrosol synthesis pathway with 4-OH-phenylpyruvate as intermediate via the overexpression of the heterologous genes tyrA_Ec^fbr and ARO10_Sc (green), encoding a feedback resistant mutant of the bifunctional chorismate mutase/prephenate dehydrogenase from E. coli and phenylpyruvate decarboxylase from S. cerevisiae, respectively. Gene deletions of qsuB and dapC, encoding 3-dehydroshikimate dehydratase and N-succinyl-aminooxopimelate aminotransferase, respectively, are indicated by red crosses. Final production titers of PCA, l-tyrosine, and tyrosol are shown for the tested strains (indicated by B–D). Native enzymes (black) are encoded by tyrA: l-arogenate decarboxylase, adh: alcohol dehydrogenase. PCA: protocatechuate; l-Glu: l-glutamate; 2-OG: 2-oxoglutarate; 4-OH: 4-hydroxy. NAD(P): nicotinamide adenine dinucleotide (phosphate). B–D Growth (CDW) and production of PCA, l-tyrosine, and tyrosol for C. glutamicum AROM3 (tyrA_Ec^fbr)(ARO10_Sc) (after 96 h, glucose was exhausted) (B), and its comparison to the respective dapC deletion strain (for which the glucose was exhausted after 144 h) (C), and further comparison to strain C. glutamicum AROM3 ΔdapC ΔqsuABD (tyrA_Ec^fbr)(ARO10_Sc) (which had depleted glucose after 72 h) (D). Values and error bars represent means and standard deviations of triplicate shake flask cultivations