The present invention provides an enzyme with lytic activity againstcariogenicbacteria and a means for treating and preventing tooth decay using the enzyme.Theenzyme provided by the present invention is a lytic enzyme produced byStreptococcusmutans and has a substrate specificity for lysing selectively Streptococcusmutans andStreptococcus sobrinus. Therefore, application of the enzyme enables to removeselectively cariogenic bacteria or to decrease the number of cariogenicbacteria insideoral cavity, and may exert preventive effect against tooth caries.
