Culturing and Isolating Capsule-Forming Pathogenic Bacterial Strains

Source: Feltwell, T., et.al. Separating Bacteria by Capsule Amount Using a Discontinuous Density Gradient. J. Vis. Exp. (2019)This video demonstrates the preparation and characterization of bacterial strains with varying capsule production. Pathogenic strains carrying different mutations in capsule-related genes are cultured, grown in liquid media, and subjected to centrifugation to distinguish capsule phenotypes based on pellet density. Buffer treatment is used to wash and stabilize the cells while preserving their capsule structures.