Penicillin tolerance among oral streptococci

penicillin tolerance was elicited in 12 of 30 stratns of vitidans streptococci isolated from the mouths of 32 healthy subject Streptococcus sanguis were the organisms most frequently tolerant but the property was also common among isolates of S. mutans, and S. mitior, S. Salivarius was rarely tolerant. When incubated with penicillin at 5 chi MIC, both tolerant and sensitive strains of oral streptococci declined in number less rapidly than S. pyogenes