Utilization of hydroxyapatite adsorbable salivary proteins as growth substrates for plaque-forming oral streptococci

Following treatment with hydroxyapatite, clarified mixed saliva from one donor source lost much of its growth-supportive activity for S. mutans VA-29R (type c). Growth of the organism in a basal medium containing proteins desorbed from HA with 0.067 M potassium phosphate buffer, pH 8.0, was accompanied by the disappearance of some of the proteins, including those with isoelectric points of 4.90, 5.72, and 6.00. These proteins are among those known to be specifically attacked by S. mutans. These findings suggest that some of the proteins selectively adsorbed from saliva with HA may serve as specific growth substrates for the plaque-forming oral streptococci.