ABSTRACT
This chapter attempts to determine the mechanism of action of interfering isolates selected because their presence in the pharyngeal flora has been associated with resistance to infection. The normal microbial flora of healthy humans is remarkably stable, both quantitatively and qualitatively. The stability appears to result from a finely "tuned" balance of dynamic interactions, rather than indifference, among the constituents of the flora. In many individuals, this complex ecosystem appears to be a first line of defense against colonization and invasion by exogenously acquired microorganisms. The process of selection and testing of individual colonies from each throat culture was cumbersome and time consuming. The presence of bactericidal organisms in the throat flora of children has been associated prospectively with resistance to acquisition of group A streptococci during two epidemics. Enocin inhibits pantothenate metabolism by group A streptococci and other pantothenate-requiring microorganisms.
