title: Use of the quorum sensing inhibitor furanone C-30 to interfere with biofilm formation by Streptococcus mutans and its luxS mutant strain.
abstract: Streptococcus mutans is recognised as a major aetiological agent of dental caries. One of its important virulence factors is its ability to form biofilms on tooth surfaces. The aim of this study was to evaluate the effects of the quorum sensing inhibitor furanone C-30 on biofilm formation by S. mutans and its luxS mutant strain. The effects of furanone C-30 on biofilms of both strains formed on 96-well microtitre plates at 37 °C were determined by a colorimetric technique (MTT assay). Different concentrations of furanone C-30 (0.0, 2.0 and 4.0 μg/mL) and different time points of biofilm formation (4, 14 and 24 h) were investigated. The structures and thickness of the biofilms were observed by confocal laser scanning microscopy (CLSM). Quorum sensing-related gene expression (ftf, smu630, brpA, gbpB, gtfB, vicR, comDE and relA) was investigated by real-time polymerase chain reaction (RT-PCR). The results showed that synthetic furanone C-30 can inhibit biofilm formation by S. mutans and its luxS mutant strain, although it does not affect the bacterial growth rate itself. The quantities of biofilm formed by both strains significantly decreased (P<0.05) and the biofilms became thinner and looser as revealed by CLSM with increasing concentrations of furanone C-30. Expression of the genes tested was downregulated in the biofilms by the addition of furanone C-30. These results revealed that synthetic furanone C-30 can effectively inhibit biofilm formation by S. mutans and its luxS mutant strain.
authors.affiliation: Shanghai Research Institute of Stomatology, Department of Endodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, 639 Zhizaoju Road, Shanghai 200011, China.
authors.forename: Zhiyan
authors.initials: Z
authors.lastname: He
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.forename: Yuejian
authors.initials: Y
authors.lastname: Hu
authors.forename: Jingping
authors.initials: J
authors.lastname: Liang
authors.forename: Yuntao
authors.initials: Y
authors.lastname: Jiang
authors.forename: Rui
authors.initials: R
authors.lastname: Ma
authors.forename: Zisheng
authors.initials: Z
authors.lastname: Tang
authors.forename: Zhengwei
authors.initials: Z
authors.lastname: Huang
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism*; D001426:Bacterial Proteins; D018441:Biofilms / Q000187:drug effects*; D013437:Carbon-Sulfur Lyases / Q000172:deficiency*; D003124:Colorimetry / Q000379:methods; D005663:Furans / Q000378:metabolism*; D020869:Gene Expression Profiling; D008826:Microbial Sensitivity Tests / Q000379:methods; D018613:Microscopy, Confocal; D053038:Quorum Sensing; D060888:Real-Time Polymerase Chain Reaction; D013194:Staining and Labeling / Q000379:methods; D013295:Streptococcus mutans / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D013778:Tetrazolium Salts / Q000378:metabolism; D013844:Thiazoles / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D005663:Furans; D013778:Tetrazolium Salts; D013844:Thiazoles; C494198:furanone C-30; D013437:Carbon-Sulfur Lyases; C117753:LuxS protein, Bacteria; C022616:thiazolyl blue