scholarly journals Effects of resveratrol on cariogenic virulence properties of Streptococcus mutans

2020 ◽  
Author(s):  
Jinheng Li ◽  
Yaqin Zhu ◽  
Tiantian Wu ◽  
Weiwei Peng

Abstract Background: Streptococcus mutans is the principal etiological agent of human dental caries. The major virulence factors of S. mutans are acid production, acid tolerance, extracellular polysaccharide (EPS) synthesis and biofilm formation. The aim of this study is to evaluate the effect of resveratrol, a natural compound, on virulence properties of S. mutans . Methods: The effect of resveratrol on acidogenicity was investigated by pH drop and lactate dehydrogenase (LDH) assay, on aciduricity through survival rate at pH 5.0 and F-ATPase assay, on EPS synthesis (including water-soluble polysaccharide and water-insoluble polysaccharide) by quantitative measurement, on biofilm formation by crystal violet assay and structure observation. The expression of related virulence genes was also detected . Results: Resveratrol at sub-MIC levels can significantly decrease acid production, acid tolerance, EPS synthesis and biofilm formation. Related virulence gene expression ( ldh , relA , gtfC , comDE ) was down-regulated with increasing concentrations of resveratrol. Conclusion: Resveratrol has an inhibitory effect on S. mutans cariogenic virulence properties and it represents a promising anticariogenic agent .

2020 ◽  
Author(s):  
Jinheng Li ◽  
Tiantian Wu ◽  
Weiwei Peng ◽  
yaqin zhu

Abstract Background: Streptococcus mutans is the principal etiological agent of human dental caries. The major virulence factors of S. mutans are acid production, acid tolerance, extracellular polysaccharide (EPS) synthesis and biofilm formation. The aim of this study is to evaluate the effect of resveratrol, a natural compound, on virulence properties of S. mutans . Results: Resveratrol at sub-MIC levels significantly decreased acid production and acid tolerance, inhibited synthesis of water-soluble polysaccharide and water-insoluble polysaccharide, compromised biofilm formation. Related virulence gene expression ( ldh, relA, gtfC, comDE ) was down-regulated with increasing concentrations of resveratrol. Conclusions : Resveratrol has an inhibitory effect on S. mutans cariogenic virulence properties and it represents a promising anticariogenic agent. Keywords : resveratrol, Streptococcus mutans , acidogenicity, aciduricity, extracellular polysaccharide, biofilm


2019 ◽  
Author(s):  
Jinheng Li ◽  
Tiantian Wu ◽  
Weiwei Peng ◽  
Yaqin Zhu

Abstract Background: Streptococcus mutans is the principal etiological agent of human dental caries. The major virulence factors of S. mutans are acid production, acid tolerance, extracellular polysaccharide (EPS) synthesis and biofilm formation. The aim of this study is to evaluate the effect of resveratrol, a natural compound, on virulence properties of S. mutans . Methods: The effect of resveratrol on acidogenicity was investigated by pH drop and lactate dehydrogenase (LDH) assay, on aciduricity through survival rate at pH 5.0 and F-ATPase assay, on EPS synthesis (including water-soluble polysaccharide and water-insoluble polysaccharide) by quantitative measurement, on biofilm formation by crystal violet assay and structure observation. The expression of related virulence genes was also detected . Results: Resveratrol at sub-MIC levels can significantly decrease acid production, acid tolerance, EPS synthesis and biofilm formation. Related virulence gene expression ( ldh , relA , gtfC , comDE ) was down-regulated with increasing concentrations of resveratrol. Conclusion: Resveratrol has an inhibitory effect on S. mutans cariogenic virulence properties and it represents a promising anticariogenic agent .


Microbiology ◽  
2010 ◽  
Vol 156 (10) ◽  
pp. 3136-3147 ◽  
Author(s):  
Sang-Joon Ahn ◽  
Kelly C. Rice ◽  
Janneth Oleas ◽  
Kenneth W. Bayles ◽  
Robert A. Burne

The tight control of autolysis by Streptococcus mutans is critical for proper virulence gene expression and biofilm formation. A pair of dicistronic operons, SMU.575/574 (lrgAB) and SMU.1701/1700 (designated cidAB), encode putative membrane proteins that share structural features with the bacteriophage-encoded holin family of proteins, which modulate host cell lysis during lytic infection. Analysis of S. mutans lrg and cid mutants revealed a role for these operons in autolysis, biofilm formation, glucosyltransferase expression and oxidative stress tolerance. Expression of lrgAB was repressed during early exponential phase and was induced over 1000-fold as cells entered late exponential phase, whereas cidAB expression declined from early to late exponential phase. A two-component system encoded immediately upstream of lrgAB (LytST) was required for activation of lrgAB expression, but not for cid expression. In addition to availability of oxygen, glucose levels were revealed to affect lrg and cid transcription differentially and significantly, probably through CcpA (carbon catabolite protein A). Collectively, these findings demonstrate that the Cid/Lrg system can affect several virulence traits of S. mutans, and its expression is controlled by two major environmental signals, oxygen and glucose. Moreover, cid/lrg expression is tightly regulated by LytST and CcpA.


2013 ◽  
Vol 80 (1) ◽  
pp. 97-103 ◽  
Author(s):  
Dan Li ◽  
Yukie Shibata ◽  
Toru Takeshita ◽  
Yoshihisa Yamashita

ABSTRACTAStreptococcus mutansmutant defective in aciduricity was constructed by random-insertion mutagenesis. Sequence analysis of the mutant revealed a mutation ingidA, which is known to be involved in tRNA modification inStreptococcus pyogenes. Complementation ofgidAbyS. pyogenesgidArecovered the acid tolerance ofS. mutans. Although thegidA-inactivatedS. pyogenesmutant exhibited significantly reduced expression of multiple extracellular virulence proteins, theS. mutansmutant did not. On the other hand, thegidAmutant ofS. mutansshowed reduced ability to withstand exposure to other stress conditions (high osmotic pressure, high temperature, and bacitracin stress) besides an acidic environment. In addition, loss of GidA decreased the capacity for glucose-dependent biofilm formation by over 50%. This study revealed thatgidAplays critical roles in the survival ofS. mutansunder stress conditions, including lower pH.


PLoS ONE ◽  
2016 ◽  
Vol 11 (12) ◽  
pp. e0168305 ◽  
Author(s):  
Mara Baldry ◽  
Anita Nielsen ◽  
Martin S. Bojer ◽  
Yu Zhao ◽  
Cathrine Friberg ◽  
...  

2021 ◽  
Vol 70 (12) ◽  
Author(s):  
Letícia T. Oliveira ◽  
Lívia A. Alves ◽  
Erika N. Harth-Chu ◽  
Ryota Nomura ◽  
Kazuhiko Nakano ◽  
...  

Introduction. Streptococcus mutans , a common species of the oral microbiome, expresses virulence genes promoting cariogenic dental biofilms, persistence in the bloodstream and cardiovascular infections. Gap statement. Virulence gene expression is variable among S. mutans strains and controlled by the transcription regulatory systems VicRK and CovR. Aim. This study investigates polymorphisms in the vicRK and covR loci in S. mutans strains isolated from the oral cavity or from the bloodstream, which were shown to differ in expression of covR, vicRK and downstream genes. Methodology. The transcriptional activities of covR, vicR and vicK were compared by RT-qPCR between blood and oral strains after exposure to human serum. PCR-amplified promoter and/or coding regions of covR and vicRK of 18 strains (11 oral and 7 blood) were sequenced and compared to the reference strain UA159. Results. Serum exposure significantly reduced covR and vicR/K transcript levels in most strains (P<0.05), but reductions were higher in oral than in blood strains. Single-nucleotide polymorphisms (SNPs) were detected in covR regulatory and coding regions, but SNPs affecting the CovR effector domain were only present in two blood strains. Although vicR was highly conserved, vicK showed several SNPs, and SNPs affecting VicK regions important for autokinase activity were found in three blood strains. Conclusions. This study reveals transcriptional and structural diversity in covR and vicR/K, and identifies polymorphisms of functional relevance in blood strains, indicating that covR and vicRK might be important loci for S. mutans adaptation to host selective pressures associated with virulence diversity.


2020 ◽  
Author(s):  
Yadong Sun ◽  
Shanshan Wen ◽  
Lili Zhao ◽  
Qiqi Xia ◽  
Yue Pan ◽  
...  

Abstract Background The aim of this study was to investigate the association among biofilm formation, virulence gene expression, and antibiotic resistance in P. mirabilis isolates collected from diarrhetic animals (n = 176) in northeast China between September 2014 and October 2016. Results Approximately 92.05% of the isolates were biofilm producers, whereas 7.95% of the isolates were non-producers. The prevalence of virulence genes in biofilm producers was significantly higher than that in non-producers. Biofilm production was significantly associated with the expression of ureC , zapA , rsmA , hmpA , mrpA , atfA , and pmfA ( P < 0.05). Drug susceptibility tests revealed that approximately 76.7% of the isolates were multidrug-resistant (MDR) and extensively drug-resistant (XDR). Biofilm production was significantly associated with resistance to doxycycline, tetracycline, sulfamethoxazole, kanamycin, and cephalothin ( P < 0.05). Although the pathogenicity of the biofilm producers was stronger than that of the non-producers, the biofilm-forming ability of the isolates was not significantly associated with morbidity and mortality in mice ( P > 0.05). Conclusion Our findings suggested that a high level of multidrug resistance in diarrhetic animals infected with P. mirabilis in northeast China.The results of this study indicated that the positive rates of the genes expressed by biofilm-producing P. mirabilis isolates were significantly higher than those expressed by non-producing isolates.


2019 ◽  
Author(s):  
Sampriti Mukherjee ◽  
Matthew Jemielita ◽  
Vasiliki Stergioula ◽  
Mikhail Tikhonov ◽  
Bonnie L. Bassler

ABSTRACTPseudomonas aeruginosa transitions between the free-swimming state and the sessile biofilm mode during its pathogenic lifestyle. We show that quorum sensing represses P. aeruginosa biofilm formation and virulence by activating expression of genes encoding the KinB-AlgB two-component system. Phospho-AlgB represses biofilm and virulence genes, while KinB dephosphorylates, and thereby, inactivates AlgB. We discover that the photoreceptor BphP is the kinase that, in response to light, phosphorylates and activates AlgB. Indeed, exposing P. aeruginosa to light represses biofilm formation and virulence gene expression. To our knowledge, P. aeruginosa was not previously known to detect light. The KinB-AlgB-BphP module is present in all Pseudomonads, and we demonstrate that AlgB is the cognate response regulator for BphP in diverse bacterial phyla. We propose that KinB-AlgB-BphP constitutes a “three-component” system and AlgB is the node at which varied sensory information is integrated. This study sets the stage for light-mediated control of P. aeruginosa infectivity.


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