Figure 3

Time course of the cultivations of L. plantarum overexpressing β-galactosidase from L. reuteri with pH control at increased glucose concentration. L. plantarum WCFS1 harbouring the pEH9R plasmid was cultivated in 400-ml laboratory fermentors at 37°C using MRS medium with 40 g/l glucose and pH control at pH 6.5. Expression of β-galactosidase was induced by the addition of varying amounts of pheromone (ng/ml fermentation broth; see insert) at different OD₆₀₀ values: immediately after inoculation (A), at OD₆₀₀ of 0.3 (B), or at OD₆₀₀ of 3.0 (C). All data points represent the average value from 2 independent experiments.