Abstract
Macromolecular solutes (albumin, concanavalin A, whole [human] saliva and serum) caused impaired sorption of Streptococcus faecium and S. sanguis to glass. The inhibitory effect is mainly due to interactions of the solutes with the glass surface. In the case of sorption of S. sanguis to glass in the presence of parotid fluid, the inhibitory effect was counteracted by a specific attachment of S. sanguis cells mediated by some component(s) of the parotid fluid. Agglutination of the test organisms was in general accompanied by inhibition of sorption, but when small or unstable aggregates were formed, the number of cells adhering on the glass surface was increased. The findings are discussed with reference to the colonization of teeth by oral bacteria.