Ruthenium red staining of exopolysaccharide produced by <i>V. cholerae</i> strains.

<p>Each <i>V. cholerae</i> strain (ca. 10⁸ cfu/ml) was grown in 3 ml FSLW and incubated overnight statically at room temperature. The cultures were stained with ruthenium red stain (as described in Methods section) and images were visualized using transmission electron microscopy (TEM). Exopolysaccharide produced by N16961R-24 is indicated by arrows; N16961S-24 and GASP-700D did not develop any exopolysaccharide. Bars = 1 μm.