Fig. 6

Qualitative and quantitative analyses of the extracellular polysaccharides of A. tertiaricarbonis wild type strain and mutants demonstrating that PepA overexpression decreased the release of soluble exopolysaccharides produced by the rpoN1 mutant. Upper panel: Ethanol-precipitated exopolysaccharides extracted from the cell free supernatants of bacterial cultures of wild type strain RN12 with the pBBR1MCS-2 empty vector (A), RN12T4 mutant with the empty vector (B), RN12T4 mutant with pBBR1MCS-2-rpoN1 (C) and RN12T4 mutant with pBBR1MCS-2-pepA (D). Lower panel: Average yields of the total cell carbohydrates (grey bars) and released soluble exopolysaccharides (S-EPS, white bars) levels of bacterial cultures of A, B, C and D were measured using the phenol-sulfuric acid method at 12 h, 18 h and 24 h (E). Values were shown as micrograms per milliliter of bacterial suspension. All experiments were performed in triplicate; Error bars represent the standard deviation