Figure 1. Effect of glucose on the biofilm forming capacity of GAS isolates belonging to different FCT-types.

Forty-four GAS clinical isolates belonging to 7 FCT-types were grown under static conditions on 24-well polystyrene plates for 12 hours in non-buffered C medium without supplemented glucose (circles) or in the same medium added with 30 mM glucose (triangles); crystal violet stained, surface-attached bacteria were quantified by solubilizing the dye and measuring the absorbance at 540 nm; each dot represents the mean value of three independent experiments performed for each of the 44 isolates.