FIG 1.

Physiological characterization of the phaR mutant under oxic or microoxic conditions. (A to F) Oxic conditions, with rotary shaking at 180 rpm in contact with the air. (A) Growth kinetics. (B) PHB extracted from 25-day-old cells. (C) EPS obtained from 25-day-old cultures. (D to F) Transmission electron micrographs of cells from 25-day-old cultures showing bright PHB granules (scale bar, 0.2 μm). (G and H) Microoxic conditions, with rotary shaking at 60 rpm in contact with an atmosphere of 0.5% O₂ and 99.5% N₂. (G) Growth kinetics. (H) PHB extracted from 11-day-old cells. In all cases, quantitative results are the average ± standard error of the mean (SEM) from four independent cultures. When error bars are not visible, they are smaller than the symbol.