Figure 2.

Evaluation of the 4-hydroxybenzoate production pathway in P. taiwanensis VLB120 CL1 in co-feeding experiments. (A) Comparison of the conversion rates of the two different pathway components (encoded by the ferulic operon and the ammonia-lyase genes). Cells were grown in biological triplicates in MSM with 5 mM glucose in System Duetz plates at 30°C and 300 rpm. After ~6 h, 3 mM 4-coumarate (ferulic operon) or tyrosine (PAL and TAL genes), and another 20 mM glucose were added. Highest measured rates are indicated. (B) 4-hydroxybenzoate production (squares) and growth (circles) of P. taiwanensis VLB120 CL1 (containing RtPAL). Cells were cultivated in triplicates in MSM supplemented with 20 mM glucose as a sole carbon source at 30°C and 300 rpm in System Duetz plates. Expression of ferulic genes was induced with 0.2 mM IPTG. Error bars indicate standard error of the mean.