scholarly journals Characterization of Recombinant, Ureolytic Streptococcus mutans Demonstrates an Inverse Relationship between Dental Plaque Ureolytic Capacity and Cariogenicity

2000 ◽  
Vol 68 (5) ◽  
pp. 2621-2629 ◽  
Author(s):  
K. Anne Clancy ◽  
Sylvia Pearson ◽  
William H. Bowen ◽  
Robert A. Burne
Keyword(s):  
Dental Caries ◽  
Streptococcus Mutans ◽  
Urease Activity ◽  
Dental Health ◽  
Oral Bacteria ◽  
Streptococcus Salivarius ◽  
Specific Pathogen ◽  
The Relationship

ABSTRACT Dental caries results from prolonged plaque acidification that leads to the establishment of a cariogenic microflora and demineralization of the tooth. Urease enzymes of oral bacteria hydrolyze urea to ammonia, which can neutralize plaque acids. To begin to examine the relationship between plaque ureolytic activity and the incidence of dental caries, recombinant, ureolytic strains ofStreptococcus mutans were constructed. Specifically, theureABCEFGD operon from Streptococcus salivarius57.I was integrated into the S. mutans chromosome in such a way that the operon was transcribed from a weak, cognate promoter inS. mutans ACUS4 or a stronger promoter in S. mutans ACUS6. Both strains expressed NiCl2-dependent urease activity, but the maximal urease levels in ACUS6 were threefold higher than those in ACUS4. In vitro pH drop experiments demonstrated that the ability of the recombinant S. mutans strains to moderate a decrease in pH during the simultaneous metabolism of glucose and urea increased proportionately with the level of urease activity expressed. Specific-pathogen-free rats that were infected with ACUS6 and fed a cariogenic diet with drinking water containing 25 mM urea and 50 μM NiCl2 had relatively high levels of oral urease activity, as well as dramatic decreases in the prevalence of smooth-surface caries and the severity of sulcal caries, relative to controls. Urease activity appears to influence plaque biochemistry and metabolism in a manner that reduces cariogenicity, suggesting that recombinant, ureolytic bacteria may be useful to promote dental health.

scholarly journals Isolation and Characterization of anti-Streptococcus Mutans Phage as a Possible Treatment Agent for Caries

2021 ◽  
Author(s):  
Hadar Ben Zaken ◽  
Reut Kraitman ◽  
Shunit Coppenhagen-Glazer ◽  
Leron Khalifa ◽  
Sivan Alkalay-Oren ◽  
...  
Keyword(s):  
Dental Caries ◽  
Streptococcus Mutans ◽  
Pathogenic Bacteria ◽  
Antibacterial Effect ◽  
Antibacterial Properties ◽  
Human Saliva ◽  
Whole Genome Sequence ◽  
Isolation And Characterization

Streptococcus mutans is a key bacterium in dental caries- one of the most prevalent chronic infectious diseases. Conventional treatment both fails to specifically target the pathogenic bacteria and at-tempts to eradicate commensal bacteria as well. Thus, caries remains one of most common and challenging diseases. The use of bacterial viruses as anti-bacterial agents, is gaining interest worldwide. Hardly any phages were described against S. mutans. The objective of this study was to isolate anti-S. mutans phages and to characterize their antimi-crobial properties. Human saliva samples were filtered and screened for potential phages. Standard double-layered agar method was used for isolation. Whole genome sequence analysis and morphology visualization by TEM, were used for anti-S. mutans phage identification. Antibacterial properties were evaluated using clinical strains and ATCC strains of S. mutans in various states. Antibacterial effect was also tested on human cariogenic dentin. One phage against S. mutans was isolated and termed SMHBZ8. This phage showed effective lytic activity in vitro against both planktonic and biofilm S. mutans cultures. Moreover, the phage showed antibacterial effect when used on cariogenic dentin. The isolation and characterization of SMHBZ8 may be the first step in developing a potential phage therapy for dental caries.

scholarly journals The Efficacy of Neem Extract on Four Microorganisms Responsible for causing Dental Caries viz Streptococcus mutans, Streptococcus salivarius, Streptococcus mitis and Streptococcus sanguis: An in vitro Study

2012 ◽  
Vol 13 (6) ◽  
pp. 769-772 ◽  
Author(s):  
Venkateswara Rao Chava ◽  
SM Manjunath ◽  
AV Rajanikanth ◽  
N Sridevi
Keyword(s):  
Dental Caries ◽  
Streptococcus Mutans ◽  
Dietary Habits ◽  
Individual Species ◽  
Streptococcus Salivarius ◽  
Streptococcus Mitis ◽  
Neem Extract ◽  
Coarse Powder ◽  
Streptococcus Sanguis

ABSTRACT History and objectives From the ancient time, neem used to be the traditional medicine for many diseases and was mainly used for cleaning the oral cavity. The incidence of dental caries was less a few decades ago but now the incidence of caries is very aggressive. This might be due to change in dietary habits, life style and more tendency toward processed food. The objective of this study is to find out the truth that if the neem is really efficacious against caries-inducing microorganisms, mainly Streptococcus mutans, Streptococcus salivarius, Streptococcus mitis and Streptococcus sanguis. Materials and methods The dried neem sticks ground into a coarse powder and weighed into 5, 10 and 50 gm were added to 100 ml of deionized double distilled water. After soaking for 2 days, the water was filtered at 4°C and the fine filtrate was inoculated onto blood agar plates contains individual species of microorganisms and incubated at 37°C for 2 days. Results At maximum concentrations, neem extract has shown the maximum zone of inhibition on Streptococcus mutans. At less concentration, the efficacy of neem has shown some inhibition of growth for all the four species of microorganisms. Conclusion Neem chewing provides the maximum benefits. Hence, the use of chewing sticks of neem can be recommended. How to cite this article Chava VR, Manjunath SM, Rajanikanth AV, Sridevi N. The Efficacy of Neem Extract on Four Microorganisms Responsible for causing Dental Caries viz Streptococcus mutans, Streptococcus salivarius, Streptococcus mitis, and Streptococcus sanguis: An in vitro Study. J Contemp Dent Pract 2012;13(6):769-772.

scholarly journals Antimicrobial action of the hydroethanolic extract of Spondias mombin L. against oral bacteria of the genus Streptococcus

2021 ◽  
Vol 10 (1) ◽  
pp. e39310111539
Author(s):  
Thais Oliveira Cordeiro ◽  
Angélica Kercya Pereira de Mendonça ◽  
Mayra Sousa Gomes ◽  
Emanuelle Louyde Ferreira de Lima ◽  
Maria Regina Macedo Costa ◽  
...  
Keyword(s):  
Streptococcus Mutans ◽  
Oral Bacteria ◽  
Antimicrobial Action ◽  
Streptococcus Salivarius ◽  
Streptococcus Mitis ◽  
Streptococcus Sanguinis ◽  
Spondias Mombin ◽  
Streptococcus Oralis ◽  
Hydroethanolic Extract

Objetivo: O objetivo do presente estudo foi avaliar in vitro a atividade antimicrobiana do extrato hidroetanólico da folha de Spondias mombin (S. mombin L.) sobre bactérias do gênero Streptococcus: S. mutans, S. mitis, S. oralis, S. sanguinis e S. salivarius, comparando-a à atividade antimicrobiana da solução de digluconato de clorexidina 0,12% sobre essas mesmas bactérias. Metodologia: Foram realizados os testes in vitro de Determinação da Concentração Inibitória Mínima, Determinação da Concentração Inibitória Mínima de Aderência e Análise da Cinética Bactericida. Resultados: Para o Streptococcus mutans, o grupo controle foi estatisticamente superior (p<0,05) ao extrato até a concentração 31,25mg/ml, não ocorrendo diferença estatística nas demais concentrações. Para o Streptococcus oralis, o extrato foi estatisticamente superior (p<0,05) ao grupo controle em sua forma bruta (500mg/ml), o grupo controle teve significância estatística (p<0,05) sobre o extrato apenas nas concentrações 62,5mg/ml, 31,25mg/ml, 1,95mg/ml e 0,97mg/ml. Para o Streptococcus sanguinis, foi constatado que o extrato foi estatisticamente superior (p<0,05) ao grupo controle nas duas primeiras concentrações 500mg/ml e 250mg/ml, ao passo que o grupo controle teve significância estatística (p<0,05) sobre o extrato apenas nas duas últimas concentrações: 1,95mg/ml e 0,97mg/ml. O grupo controle foi estatisticamente superior (p<0,05) ao extrato em todas as concentrações no Streptococcus mitis, exceto para a concentração 31,25mg/ml. Para a Streptococcus salivarius, o extrato foi estatisticamente superior (p<0,05) ao grupo controle na maioria das concentrações testadas, com exceção apenas para 15,65mg/ml e 1,95mg/ml, que não foram observados diferenças estatisticamente significativas entre o extrato e o grupo controle. Conclusão: o extrato hidroetanólico de Spondias mombin L., em diferentes concentrações, apresenta atividade antimicrobiana semelhante ao digluconato de clorexidina a 0,12% frente a bactérias bucais do gênero Streptococcus.

scholarly journals Pharmaceutical properties of 'sucupira' (Pterodon spp.)

2010 ◽  
Vol 46 (4) ◽  
pp. 607-616 ◽  
Author(s):  
Daiane Hansen ◽  
Mitsue Haraguchi ◽  
Antonio Alonso
Keyword(s):  
Biological Effects ◽  
Chemical Compounds ◽  
Experimental Models ◽  
Popular Medicine ◽  
Isolation And Characterization ◽  
Pharmaceutical Properties ◽  
The Relationship

The plant of the genus Pterodon (Fabaceae, Leguminosae), commonly known as 'sucupira' or 'faveira', are disseminated throughout the central region of Brazil and has frequently been used in popular medicine for its anti-rheumatic, analgesic, and anti-inflammatory properties. In recent years, interest in these plants has increased considerably. The biological effects of different phytoextracts and pure metabolites have been investigated in several experimental models in vivo and in vitro. The literature describes flavonoids, triterpene and steroids, while one paper presented studies with proteins isolated from the genus. This review provides an overview of phytochemical and pharmacological research in Pterodon, showing the main chemical compounds studied to date, and focusing on the relationship between these molecules and their biological activity. Furthermore, this study paves the way for more in-depth investigation, isolation and characterization of the molecules of this plant genus.

scholarly journals Anti-bacterial activity of three essential oils - An in vitro study

2019 ◽  
Vol 10 (2) ◽  
pp. 1049-1053 ◽  
Author(s):  
Geetha RV ◽  
John Rozar Raj B ◽  
Lakshmi Thangavelu
Keyword(s):  
Antibacterial Activity ◽  
Essential Oils ◽  
Streptococcus Mutans ◽  
Bacterial Species ◽  
In Vitro Study ◽  
Oral Bacteria ◽  
Zone Of Inhibition ◽  
Thyme Oil ◽  
Rosemary Oil

To conduct a study regarding the antibacterial activity of essential oils against bacteria causing Caries. Essential oils are distillates of the volatile compounds of a plant’s secondary metabolism and may act as photoprotective agents. Their curative effect has been known since antiquity. It is based on a variety of pharmacological properties which are specific for each plant species. The mouth contains a variety of oral bacteria, but only a few species of bacteria are believed to cause dental caries. Antibacterial activity of the three essential oils, Rosemary oil, Holy basil oil, Thyme oil was screened against Streptococcus mutans, using disc diffusion technique. The rosemary oil was more effective against Streptococcus mutans with a zone of inhibition of 52 mm diameter (at concentration 200 µl), Rosemary oil showed a zone of inhibition of 44 mm diameter and with thyme oil, the zone diameter was 30 mm. The results of this study showed that the essential oils at different concentrations exhibited antibacterial activity against the bacterial species tested.

scholarly journals Synergism of Streptococcus mutans and Candida albicans Reinforces Biofilm Maturation and Acidogenicity in Saliva: An In Vitro Study

2021 ◽  
Vol 10 ◽  
Author(s):  
Hye-Eun Kim ◽  
Yuan Liu ◽  
Atul Dhall ◽  
Marwa Bawazir ◽  
Hyun Koo ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Dental Caries ◽  
Streptococcus Mutans ◽  
Critical Role ◽  
In Vitro Study ◽  
Acidic Ph ◽  
Acidic Environment ◽  
Symbiotic Interaction ◽  
Biofilm Development

Early childhood caries, a virulent-form of dental caries, is painful, difficult, and costly to treat that has been associated with high levels of Streptococcus mutans (Sm) and Candida albicans (Ca) in plaque-biofilms on teeth. These microorganisms appear to develop a symbiotic cross-kingdom interaction that amplifies the virulence of plaque-biofilms. Although biofilm studies reveal synergistic bacterial-fungal association, how these organisms modulate cross-kingdom biofilm formation and enhance its virulence in the presence of saliva remain largely unknown. Here, we compared the properties of Sm and Sm-Ca biofilms cultured in saliva by examining the biofilm structural organization and capability to sustain an acidic pH environment conducive to enamel demineralization. Intriguingly, Sm-Ca biofilm is rapidly matured and maintained acidic pH-values (~4.3), while Sm biofilm development was retarded and failed to create an acidic environment when cultured in saliva. In turn, the human enamel slab surface was severely demineralized by Sm-Ca biofilms, while there was minimal damage to the enamel surface by Sm biofilm. Interestingly, Sm-Ca biofilms exhibited an acidic environment regardless of their hyphal formation ability. Our data reveal the critical role of symbiotic interaction between S. mutans and C. albicans in human saliva in the context of pathogenesis of dental caries, which may explain how the cross-kingdom interaction contributes to enhanced virulence of plaque-biofilm in the oral cavity.

scholarly journals Preparation, characterisation and microbiological examination of Pickering nano-emulsions containing essential oils, and their effect on Streptococcus mutans biofilm treatment

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Barbara Horváth ◽  
Viktória L. Balázs ◽  
Adorján Varga ◽  
Andrea Böszörményi ◽  
Béla Kocsis ◽  
...  
Keyword(s):  
Essential Oils ◽  
Streptococcus Mutans ◽  
Dental Health ◽  
Model Membrane ◽  
Biofilm Model ◽  
Mouth Care ◽  
Modified Silica Nanoparticles ◽  
Surface Modified ◽  
20 Nm

Abstract Essential oils (EOs) are commonly applied in mouth care products like mouthwashes, mostly as an ethanolic solution or by usage of surfactants as solubilising agents. In this study, we present a formulation for preparation of Pickering nano-emulsions (PnE) of EOs as a novel form for application of EOs in mouth care. For the preparation of PnE, we have synthesised surface-modified silica nanoparticles with a mean diameter of 20 nm, as well as we have examined the effect of EOs concentration on PnE droplet size and stability. In vitro study of their effect on the Streptococcus mutans biofilm as the main pathogen of dental health problems has been performed. We have found that EOs in the PnE form has the highest effectiveness against biofilm formation. Diffusion through the biofilm model membrane was studied to explain this observation. We have found that PnEs have a better performance in the transportation of EOs trough model membrane than the ethanolic solutions and conventional emulsions (CEs).

scholarly journals Characterization of the Urease Operon of Brucella abortus and Assessment of Its Role in Virulence of the Bacterium

2006 ◽  
Vol 75 (2) ◽  
pp. 774-780 ◽  
Author(s):  
Félix J. Sangari ◽  
Asunción Seoane ◽  
María Cruz Rodríguez ◽  
Jesús Agüero ◽  
Juan M. García Lobo
Keyword(s):  
Brucella Abortus ◽  
Urease Activity ◽  
Strong Acid ◽  
Oral Route ◽  
Open Reading Frames ◽  
Human Brucellosis ◽  
Major Route

ABSTRACT Most members of the genus Brucella show strong urease activity. However, the role of this enzyme in the pathogenesis of Brucella infections is poorly understood. We isolated several Tn5 insertion mutants deficient in urease activity from Brucella abortus strain 2308. The mutations of most of these mutants mapped to a 5.7-kbp DNA region essential for urease activity. Sequencing of this region, designated ure1, revealed the presence of seven open reading frames corresponding to the urease structural proteins (UreA, UreB, and UreC) and the accessory proteins (UreD, UreE, UreF, and UreG). In addition to the urease genes, another gene (cobT) was identified, and inactivation of this gene affected urease activity in Brucella. Subsequent analysis of the previously described sequences of the genomes of Brucella spp. revealed the presence of a second urease cluster, ure2, in all them. The ure2 locus was apparently inactive in B. abortus 2308. Urease-deficient mutants were used to evaluate the role of urease in Brucella pathogenesis. The urease-producing strains were found to be resistant in vitro to strong acid conditions in the presence of urea, while urease-negative mutants were susceptible to acid treatment. Similarly, the urease-negative mutants were killed more efficiently than the urease-producing strains during transit through the stomach. These results suggested that urease protects brucellae during their passage through the stomach when the bacteria are acquired by the oral route, which is the major route of infection in human brucellosis.

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