FIG 3.

Expression of the pvdS gene (a) and PVD production (b) at different time points. (a) Strain YL-1 was precultured in four different liquid media: (i) LB medium, (ii) LB medium (200 μM DSX), (iii) SM, and (iv) SM (50 μM FeCl₃). The total RNA at different time points was extracted and reverse transcribed. The 16S rRNA gene of strain YL-1 was used as an internal control for the real-time PCR assay. The expression of the pvdS gene in liquid LB medium for 3 h was used as the baseline. The relative quantification (RQ) values were calculated using the formula RQ = 2^{[ΔCT(pvdS in each treatment) − ΔCT(pvdS in LB, 3 h)]}. (b) PVD production of strain YL-1 in liquid SM was measured by analyzing the OD₄₀₅/OD₆₀₀ at different time points.