Figure 2From: Engineering Escherichia coli to overproduce aromatic amino acids and derived compounds Biosynthetic pathways for the production of diverse aromatic metabolites by combination of heterologous expression modules with the overproduction of intermediates from SHK- and terminal AAA pathways in Escherichia coli. Salvianic acid from HPP: (a) hpaBC (codes for an endogenous hydroxylase) of E. coli and ldh (lactate dehydrogenase) of Lactobacillus pentosus[94]. 2S-pinocembrin from L-PHE and malonyl-CoA: (b) aroF and pheA fbr of E. coli; (c) PAL (phenylalanine ammonia lyase) of Rhodotorula glutinis and 4CL (4-coumarate-CoA ligase) of Petroselium crispum; (d) CHS (chalcone synthase) of Petunia x hybrida and CHI (chalcone isomerase) of Medicago sativa; (e) matB and matC (coding for malonate synthetase and malonate carrier protein) of Rhizobium trifolii[98]. δ-tocotrienol (f) via MGGBQ (2-methyl-6-geranylgeranyl-benzoquinol) (g) from HPP and δ-tocopherol via GGPP (geranylgeranylpyrophosphate): ggh (geranylgeranylpyrophosphate reductase) of Synechocystis sp., crtE (geranylgeranylpyrophosphate synthase) of Pantoea ananatis, hpt (homogentisate phytyltransferase) of Synechocystis sp., hpd (p-hydroxyphenylpyruvate dioxygenase) of Pseudomonas putida, vte1 (tocopherol-cyclase) of Arabidopsis thaliana[95], idi (isopentenyl-diphosphate isomerase) and dxs (1-deoxyxylulose-5-phosphate synthase) of E. coli[96]. Caffeic and ferulic acids from L-TYR: (h) TAL (tyrosine ammonia lyase) and Sam5 (4-coumarate hydroxylase) of Saccharothrix espanaensis and COM (caffeic acid methyltransferase) of Arabidopsis thaliana[103]; (i) TAL of R. glutinis and (j) Coum3H (4-coumarate hydroxylase) of S. espanaensis[104]. Resveratrol from L-TYR and malonyl-CoA: (k) TAL of R. glutinis and 4CL of P. crispum; (l) STS (stilbene synthase) of Vitis vinifera; (m) matB and matC of R. trifolii[99]. Deoxyviolacein and violacein from L-TRP: (n) vioABCD genes of Chromobacterium violaceum and (o) vioE of Janthinobacterium lividum[82]. Continuous arrows show unique enzymatic reactions; dashed arrows show several enzymatic reactions. GAP: glyceraldehyde-3-phosphate. c, indicates chromosomal integration. p, indicates plasmid expression module. fbr, feedback resistant gene. op, codon-optimized gene. ↱, promoter.Back to article page