Bacteroides gingivalis vesicles mediate attachment of streptococci to serum-coated hydroxyapatite

Outer membrane vesicles purified from Bacteroides gingivalis culture supernatant bound to serum coated hydroxyapatite (SeHA). The immobilized vesicles served as receptors for a number of species of oral streptococci. The binding of Streptococcus sanguis 12 to SeHA was increased 10 times by the vesicles. Vesicle-associated binding increased proportionally with an increase in the number of bound vesicles. Arginine and lactose both partially reduced binding of S. sanguis. Heating the vesicles destroyed their binding ability whereas heating S. sanguis reduced but did not eliminate vesicle-mediated binding.