Inhibition of some normal and pathogenic vaginal bacteria by oral and vaginal streptococci

Hemolytic and nonhemolytic strains of Streptococcus faecalis, together with some strains of oral and vaginal alpha-hemolytic streptococci, produced one or more factors that inhibited the growth of Gardnerella vaginalis, Neisseria gonorrhoeae, and a variety of other vaginal bacteria. Some streptococci were inhibitory to indicator organisms only in the presence of catalase, whereas catalase either enhanced or prevented inhibitory action for still other streptococci. The inhibitors produced by certain streptococci resembled enterococcal bacteriocins, which have not previously been found to inhibit G. vaginalis or N. gonorrhoeae.