Production of p-amino-l-phenylalanine (l-PAPA) from glycerol by metabolic grafting of Escherichia coli

Table 2 Formation of l-PAPA in E. coli wild-type strain with different plasmid combinations

Plasmid combination	Final OD (600 nm)	Yield l-PAPA/glycerol (g g⁻¹)	Final l-PAPA titer (mg l⁻¹)
pJF119EH/pJNT522	5.89 ± 0.35	0	0
pC53BC/pJNT522	5.01 ± 0.95	0.01	43.2 ± 2
pC53BC/pJNT-aroFBL	4.75 ± 0.85	0.02	86.6 ± 4

E. coli LJ110 wild-type strain was transformed with two different and compatible IPTG-inducible plasmids (control plasmids pJF119EH and pJNT522) to study the effects of the presence of pabAB, papBC, and aroFBL genes, respectively. pC53BC carries pabAB and papBC as a gene cassette under the control of a Ptac promoter. To study the effect of enhanced flux through the aromatic pathway, aroFBL were cloned onto pJNT522 plasmid. Biomass yields after 48 h of cultivation in minimal media with 5 g l⁻¹ glycerol are shown as OD₆₀₀ values. The cultivations were performed in triplicate and mean values and standard deviations are given

ISSN: 1475-2859