Identification and partial characterization of a pheromone-induced adhesive surface antigen of Streptococcus faecalis.

A surface protein antigen that is produced only during the induction of aggregation of Streptococcus faecalis was shown to contribute to and perhaps be primarily responsible for aggregation. The antigen is an immunodominant surface component of induced cells. F(ab) fragments of immunoglobulins specific for this antigen prevented aggregation, providing direct evidence that the antigen is an adhesin. Consistent with this proposed association was the coincident timing of appearance of the antigen and the timing of aggregation after induction.