Spontaneously Arising Streptococcus mutans Variants with Reduced Susceptibility to Chlorhexidine Display Genetic Defects and Diminished Fitness.

ABSTRACT: Chlorhexidine (CHX) has been used to control dental caries caused by acid-tolerant bacteria such as Streptococcus mutans since the 1970s. Repeat CHX exposure for other bacterial species results in the development of variants with reduced susceptibility that also become more resistant to other antimicrobials. It has not been tested if such variants arise when streptococci are exposed to CHX. Here, we passaged S. mutans in increasing concentrations of CHX and isolated spontaneously arising reduced susceptibility variants (RSVs) from separate lineages that have MICs that are up to 3-fold greater than the parental strain. The RSVs have increased growth rates at neutral pH and under acidic conditions in the presence of CHX but accumulate less biomass in biofil

SUBMITTER: Kaspar JR 

PROVIDER: S-EPMC6591629 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature