Coaggregation between Porphyromonas gingivalis and Mutans Streptococci

Coaggregation occurred between Porphyromonas gingivalis and mutans streptococci. The coaggregation was completely inhibited by L-arginine, Nα-p-tosyl-L-lysine chloromethyl ketone (TLCK), and a trypsin inhibitor, and weakly inhibited by L-lysine, N-ethylmaleimide, lysozyme, and human whole saliva. The results of heat and proteinase K treatment suggested that a heat-labile proteinaceous substance of P. gingivalis and a heat-stable substance of mutans streptococci may play a role in the coaggregation. Mutans streptococci also aggregated in the presence of the heat-labile factor in the supernatant of P. gingivalis. The aggregation was also inhibited by L-arginine, TLCK, and a trypsin inhibitor.