Adherence, coaggregation, and hydrophobicity of Streptococcus gordonii associated with expression of cell surface lipoproteins.

Streptococcus gordonii Challis incorporated exogenous [3H]palmitate into 13 polypeptides extractable from intact cells with sodium dodecyl sulfate. A 76-kDa surface-exposed polypeptide, implicated previously as a cell aggregation determinant, was shown to be one of these lipid-modified polypeptides. Differences in sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns of lipopolypeptides were detected with mutants of S. gordonii that were altered in adherence, aggregation, coaggregation, or hydrophobicity. Lipid-modified polypeptides, tightly associated with the cell membrane, may be involved in the expression of cell surface properties of S. gordonii important for colonization of the human oral cavity.