Interactions between salivary agglutinins and strains ofStreptococcus mutanswith varying degrees of surface hydrophobicity

Abstract

Subcultured variant strains of Streptococcus mutans serotype c with a decreased surface hydrophobicity were agglutinated to a lower extent by parotid saliva or salivary agglutinin as compared with their parent strains. The variant cells also absorbed less agglutinin than the parent cells. Strains of serotype dg of S. mutans, which had an unchanged surface hydrophobicity after subculturing, showed a similar degree of agglutination before and after subculturing. Thus, hydrophobic interaction seems to be involved in binding between S. mutans cells and salivary agglutinin. Caution should be exercised when interpreting results on saliva-mediated agglutination using subcultured laboratory strains.