Efflux inhibitor suppresses Streptococcus mutans virulence properties.
It is well established that efflux pumps play important roles in bacterial pathogenicity and efflux inhibitors (EIs) have been proved to be effective in suppressing bacterial virulence properties. However, little is known regarding the EI of Streptococcus mutans, a well-known caries-inducing bacterium. In this study, we identified the EI of S. mutans through ethidium bromide efflux assay and investigated how EI affected S. mutans virulence regarding the cariogenicity and stress response. Results indicated that reserpine, the identified EI, suppressed acid tolerance, mutacin production and transformation efficiency of S. mutans, and modified biofilm architecture and extracellular polysaccharide distribution. Suppressed glycosyltransferase activity was also noted after reserpine exposure. The data from quantitative real-time-PCR demonstrated that reserpine significantly altered the expression profile of quorum-sensing and virulence-associated genes. These findings suggest that reserpine represents a promising adjunct anticariogenic agent in that it suppresses virulence properties of S. mutans.
Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-Sen University, Guangzhou, China.|Applied Oral Sciences, Faculty of Dentistry, University of HongKong, HongKong.
Huihui
H
Zeng
Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-Sen University, Guangzhou, China.
Jia
J
Liu
Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-Sen University, Guangzhou, China.
Junqi
J
Ling
D001426:Bacterial Proteins / Q000378:metabolism; D001430:Bacteriocins / Q000378:metabolism; D018441:Biofilms / Q000187:drug effects; D003731:Dental Caries / Q000188:drug therapy / Q000382:microbiology; D016695:Glycosyltransferases / Q000037:antagonists & inhibitors; D016623:Ion Pumps / Q000037:antagonists & inhibitors*; D008826:Microbial Sensitivity Tests; D053038:Quorum Sensing / Q000187:drug effects; D060888:Real-Time Polymerase Chain Reaction; D012110:Reserpine / Q000494:pharmacology*; D013295:Streptococcus mutans / Q000187:drug effects* / Q000235:genetics / Q000472:pathogenicity*; D014774:Virulence / Q000187:drug effects / Q000235:genetics
D001426:Bacterial Proteins; D001430:Bacteriocins; D016623:Ion Pumps; C476644:mutacin III, Streptococcus mutans; D012110:Reserpine; D016695:Glycosyltransferases
Streptococcus mutans; biofilm; caries; efflux; efflux inhibitors; virulence