Fig. 3

Cultivation of U. maydis AB33P5ΔR/AtPgaX with varying galacturonic acid and buffer concentrations. The medium was supplemented with glucose (4 g/L) and varying amounts of initial galacturonic acid (GalA₀) and MOPS buffer. 0, 4.5, 8.8, 12.8, 16.9, 21.7, 26.1 and 34.6 g/L GalA₀ was supplemented with 0.1, 0.1, 0.1, 0.15, 0.2, 0.25, 0.3 and 0.4 M MOPS, respectively. a Oxygen transfer rate. The galacturonic acid consumption phase is indicated by the shaded area below the OTR curve for each cultivation. b Dashed lines represent the predicted residual substrate concentration in the culture medium (GalA_calc) according to Eq. (6). Symbols represent offline measured values (GalA_meas). Culture conditions: modified Verduyn medium, initial pH 6.5, 250 mL flask, filling volume 20 mL, shaking frequency 300 rpm, shaking diameter 50 mm, initial OD₆₀₀ = 0.65, T = 30 °C