Growth, PHB accumulation, and motility profiles of H. seropedicae SmR1 and the ΔfliA mutant. (A) Bacteria were grown in NFbHPN-malate medium with 20 mM ammonium chloride and 37 mM dl-malate at 30°C and 120 rpm (orbital shaking). Bacterial growth was measured in function of the OD600 from three independent cultures. (B) PHB contents were measured by whole-cell methanolysis and gas chromatography from three independent samples of each strain when they reached an OD600 of 1.0 cultivated under the same conditions as for panel A. The quantity of accumulated PHB was normalized by the cell dry weight of lyophilized bacterial cultures used in the experiment. (C) Soft agar motility phenotype of Herbaspirillum seropedicae SmR1 and the ΔfliA mutant. The photographs are representative of four independent experiments. Overnight cultures were inoculated in the center of the plates containing NFbHPN-malate semisolid agar (0.25%, m/v) with 20 mM ammonium chloride and 37 mM dl-malate. The plates were incubated at 30°C and photographed every 24 h. Strain SmR1 and the ΔfliA mutant showed statistical significance against the other strains employed in the experiment (*, P value ≤ 0.01 [0.0098]) by the one-way ANOVA, post hoc Tukey test (P < 0.05).