Fig 4.

Biofilm formation by Granulicatella spp. in the presence or absence of F. nucleatum and A. actinomycetemcomitans strains. Bacterial strains were cultured separately or together with a partner species in 24-well plates in brucella broth in anaerobic atmosphere for 3 days as described in the methods section. After the incubation period, biofilms were washed gently to remove unattached cells and stained with 2 % crystal violet for quantifying biofilm mass. Abbreviations: Fn F. nucleatum, Ge G elegans, Ga G. adiacens, Aa A. actinomycetemcomitans. The results are means (SD) from 3 independent experiments. *p < 0.05