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Mutacins of Streptococcus mutans
Kamiya, Regianne Umeko;Taiete, Tiago;Gon?alves, Reginaldo Bruno;
Brazilian Journal of Microbiology , 2011, DOI: 10.1590/S1517-83822011000400001
Abstract: the colonization and accumulation of streptococcus mutans are influenced by various factors in the oral cavity, such as nutrition and hygiene conditions of the host, salivary components, cleaning power and salivary flow and characteristics related with microbial virulence factors. among these virulence factors, the ability to synthesize glucan of adhesion, glucan-binding proteins, lactic acid and bacteriocins could modify the infection process and pathogenesis of this species in the dental biofilm. this review will describe the role of mutacins in transmission, colonization, and/or establishment of s. mutans, the major etiological agent of human dental caries. in addition, we will describe the method for detecting the production of these inhibitory substances in vitro (mutacin typing), classification and diversity of mutacins and the regulatory mechanisms related to its synthesis.
Streptococcus mutans, Caries and Simulation Models  [PDF]
Sofia D. Forssten,Marika Bj?rklund,Arthur C. Ouwehand
Nutrients , 2010, DOI: 10.3390/nu2030290
Abstract: Dental caries and dental plaque are among the most common diseases worldwide, and are caused by a mixture of microorganisms and food debris. Specific types of acid-producing bacteria, especially Streptococcus mutans, colonize the dental surface and cause damage to the hard tooth structure in the presence of fermentable carbohydrates e.g., sucrose and fructose. This paper reviews the link between S. mutans and caries, as well as different simulation models that are available for studying caries. These models offer a valuable approach to study cariogenicity of different substrates as well as colonization of S. mutans.
Analysis of the in vitro adherence of Streptococcus mutans and Candida albicans
Barbieri, Dicler de Sant'Anna Vitor;Vicente, Vania Aparecida;Fraiz, Fabian Calixto;Lavoranti, Osmir José;Svidzinski, Terezinha Inês Estivalet;Pinheiro, Rosangela Lameira;
Brazilian Journal of Microbiology , 2007, DOI: 10.1590/S1517-83822007000400009
Abstract: the objective of the present study was to investigate the in vitro adherence capacity of streptococcus mutans and candida albicans. adherence assays were conducted on dental surfaces and analyzed by scanning electron microscopy (sem). extracted human teeth were inoculated with streptococcus mutans or candida albicans and with both species simultaneously, and incubated at 37oc for 21 days. bacterial inocula had been obtained from saliva samples of children that had been colonized by both organisms. atcc reference strains were used as controls. sem analyses showed that the biofilm that covered the entire analyzed dental surface was more homogeneous inoculated with the two microorganisms simultaneously than with each species separately. in a second experiment, carried out with isolates that had shown the highest adherence the isolates were tested for adherence to high-density polyethylene substrates. the potentialization of the adherence capacity of streptococcus mutans and candida albicans when in association was confirmed.
Genetic polymorphism of Streptococcus mutans in Brazilian family members
Spolidorio, Denise Madalena Palomari;H?fling, José Francisco;Pizzolitto, Ant?nio Carlos;Rosa, Edvaldo Antonio;Negrini, Thaís de Cássia;Spolidorio, Luís Carlos;
Brazilian Journal of Microbiology , 2003, DOI: 10.1590/S1517-83822003000300006
Abstract: the aim of this study was to determine whether random amplified polymorphic dna (ap-pcr) analysis is able to differentiate genetically different clones of mutans streptococci, in 22 brazilian family members. stimulated saliva samples were collected from fathers, mothers and infants. for 5-18 months babies with erupting primary dentition, plaque samples were collected using sterile tooth pick tips. from these samples, mutans streptococci were isolated on sb-20 agar plates. after growth, representative colonies were identified by biochemical methods on the basis of carbohydrate fermentation. streptococcus mutans isolates were obtained from all family members and ap-pcr typed separately with a random primer (opa-13). bacterial cell lysates were used as template in pcr reactions and the amplified dna fragments obtained were compared by agarose gel electrophoresis. results demonstrated that the father shared the baby's genotype in three families and the mother shared the baby's genotype in 12 families seven babies harbored streptococcus mutans strains similar to those of their siblings. the technique was able to demonstrate the genetic streptococcus mutans in brazilian family members.
A proteomic approach for exploring biofilm in Streptococcus mutans  [cached]
Asad Ullah Khan,Shahper N Khan,Mohammad Akram,Barira Islam
Bioinformation , 2011,
Abstract: Biofilm formation by Streptococcus mutans is considered as its principal virulence factor, causing dental caries. Mutants of S. mutans defective in biofilm formation were generated and analyzed to study the collective role of proteins in its formation. Mutants were characterized on the basis of adherence to saliva-coated surface, and biofilm formation. The confocal laser microscopy and scanning electron microscopy images showed that the control biofilms had cluster of cells covered by layer of exo-polysaccharide while the biofilms of mutants were thin and spaced. Two-dimensional protein electrophoresis data analysis identfied 57 proteins that are either up (44 proteins) or down (13 proteins) regulated. These data points to the importance of up and down regulated proteins in the formation of biofilm in Streptococcus mutans.
Dynamic Production of Soluble Extracellular Polysaccharides by Streptococcus mutans  [PDF]
Eva-Maria Decker,Ilka Dietrich,Christian Klein,Christiane von Ohle
International Journal of Dentistry , 2011, DOI: 10.1155/2011/435830
Abstract: Caries development in the presence of Streptococcus mutans is associated not only with the production of extracellular water-insoluble polymers but also is based on water-soluble polysaccharides. The aim of this study was the evaluation of a novel glucan-specific Lectin assay for monitoring water-soluble EPS produced by S. mutans during several growth periods in different media. S. mutans cultures were grown for 24?h, 48?h, and 144?h in medium deficient of sucrose (A) and medium supplemented with 5% sucrose (B). Microtiter well plates were coated with cell-free supernatants followed by the addition of labeled Concanavalin-A and enzyme substrate. The substrate reactions were kinetically detected at 405?nm. The validation of the assay was performed using carbohydrates dextran, xanthan, and sucrose as reference. This new Concanavalin-A-based assay showed the highest sensitivity for dextran and revealed that the glucan production of S. mutans reached its maximum at 144?h in medium B according to bacterial maturation. 1. Introduction The etiology of dental caries is often associated with increasing amounts of various acidogenic microorganisms like Streptococcus mutans which plays a keyrole in the formation of cariogenic biofilms [1]. The structural and functional properties of biofilms, like human dental plaque, are essentially determined by the presence of microbial hydrated polymers which are mainly composed of the self-produced extracellular polysaccharides (EPSs) and also of proteins, nucleic acids, phospholipids, mucosal cells, and nutrient components [1, 2]. Particularly, the EPSs produced by S. mutans contribute to the cariogenic potential of dental biofilms and their resistance to oral hygiene measures [3]. The EPSs of S. mutans during sugar exposure consist predominantly of glucose polymers (glucans) containing various proportions and branches of alpha-1.3 (water-insoluble) and alpha-1.6 (water-soluble) glucosidic linkages [4]. The sucrose and glucose metabolism of S. mutans involves versatile interactions and regulation of different extracellular glucosyltransferases: GtfB (water-insoluble glucan, ISG; low-molecular-weight water-soluble glucan, SG), GtfC (ISG and SG), GtfD (SG), and FtfF (water-soluble fructose polymers) [5]. Most studies addressing the microbial interrelationship of caries are focused on the relevance of water-insoluble EPSs produced by mutans streptococci and their genetic regulation [6]. Soluble carbohydrate polymers and their synthesizing enzymes have been shown to play another important role for the enhancement of caries
Streptococcus mutans attachment on a cast titanium surface
Rocha, Sicknan Soares da;Bernardi, Adilson César Abreu;Pizzolitto, Ant?nio Carlos;Adabo, Gelson Luis;Pizzolitto, Elisabeth Loshchagin;
Materials Research , 2009, DOI: 10.1590/S1516-14392009000100003
Abstract: this study examined by means of scanning electron microscopy (sem), the attachment of streptococcus mutans and the corrosion of cast commercially pure titanium, used in dental dentures. the sample discs were cast in commercially pure titanium using the vacuum-pressure machine (rematitan system). the surfaces of each metal were ground and polished with sandpaper (#300-4000) and alumina paste (0.3 μm). the roughness of the surface (ra) was measured using the surfcorder rugosimeter se 1700. four coupons were inserted separately into falcon tubes contained mueller hinton broth inoculated with s. mutans atcc 25175 (109 cuf) and incubated at 37 °c. the culture medium was changed every three days during a 365-day period, after which the falcons were prepared for observations by sem. the mean ra value of cp ti was 0.1527 μm. after s. mutans biofilm removal, pits of corrosion were observed. despite the low roughness, s. mutans attachment and biofilm formation was observed, which induced a surface corrosion of the cast pure titanium.
Production of monoclonal antibodies against Streptococcus mutans antigens
Canettieri, Antonio Carlos Victor;Kretchetoff, Fujiko Yamasiro;Koga-Ito, Cristiane Yumi;Moreira, Daniella;Fujarra, Fabio José Condino;Unterkircher, Carmelinda Schmidt;
Brazilian Oral Research , 2006, DOI: 10.1590/S1806-83242006000400003
Abstract: several studies have been conducted in the last decades aiming to obtain an anti-caries vaccine, however some studies have demonstrated cross reactivity between streptococcus mutans surface antigens and the human cardiac tissue. in this work, the reactivity of five anti-streptococcus mutans monoclonal antibodies (moab) (24a, 56g, c8, e8 and f6) was tested against oral streptococci, cardiac antigens and skeletal and cardiac myosins, aiming to evaluate the specificity of these moab. the hybrid producers of immunoglobulins of the igg2b class were cloned by limit dilution and expanded in vivo. moab were tested by elisa. the hybrid 24a reacted with s. mutans cct 1910, s. salivarius cct 0365 and s. pyogenes t23. no reactivity difference was observed among the tested species. cross reactivity with heart and cardiac myosin was not confirmed and only reaction with myosin of skeletal muscle was observed (p = 0.0381). the hybrid 56g reacted with all the tested microorganisms and there was statistically significant difference between s. mutans and s. pyogenes t23 (p < 0.001). this hybrid also reacted with myosin of skeletal muscle (p = 0.0095). c8, e8 and f6 presented low reactivity against oral streptococci strains and no reactivity against cardiac antigens. the data of this study showed that the 24a and 56g anti-s. mutans moab presented reactivity with s. pyogenes and s. salivarius, reinforcing the occurrence of common antigens between these species. the tested moab presented low cross-reactivity with myosin of skeletal muscle, but anti-heart activity could not be confirmed.
Generation of Diversity in Streptococcus mutans Genes Demonstrated by MLST  [PDF]
Thuy Do,Steven C. Gilbert,Douglas Clark,Farida Ali,Clarissa C. Fatturi Parolo,Marisa Maltz,Roy R. Russell,Peter Holbrook,William G. Wade,David Beighton
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0009073
Abstract: Streptococcus mutans, consisting of serotypes c, e, f and k, is an oral aciduric organism associated with the initiation and progression of dental caries. A total of 135 independent Streptococcus mutans strains from caries-free and caries-active subjects isolated from various geographical locations were examined in two versions of an MLST scheme consisting of either 6 housekeeping genes [accC (acetyl-CoA carboxylase biotin carboxylase subunit), gki (glucokinase), lepA (GTP-binding protein), recP (transketolase), sodA (superoxide dismutase), and tyrS (tyrosyl-tRNA synthetase)] or the housekeeping genes supplemented with 2 extracellular putative virulence genes [gtfB (glucosyltransferase B) and spaP (surface protein antigen I/II)] to increase sequence type diversity. The number of alleles found varied between 20 (lepA) and 37 (spaP). Overall, 121 sequence types (STs) were defined using the housekeeping genes alone and 122 with all genes. However π, nucleotide diversity per site, was low for all loci being in the range 0.019–0.007. The virulence genes exhibited the greatest nucleotide diversity and the recombination/mutation ratio was 0.67 [95% confidence interval 0.3–1.15] compared to 8.3 [95% confidence interval 5.0–14.5] for the 6 concatenated housekeeping genes alone. The ML trees generated for individual MLST loci were significantly incongruent and not significantly different from random trees. Analysis using ClonalFrame indicated that the majority of isolates were singletons and no evidence for a clonal structure or evidence to support serotype c strains as the ancestral S. mutans strain was apparent. There was also no evidence of a geographical distribution of individual isolates or that particular isolate clusters were associated with caries. The overall low sequence diversity suggests that S. mutans is a newly emerged species which has not accumulated large numbers of mutations but those that have occurred have been shuffled as a consequence of intra-species recombination generating genotypes which can be readily distinguished by sequence analysis.
Oral colonization by Streptococcus mutans and its association with the severity of periodontal disease in adults
Contardo,MS; Díaz,N; Lobos,O; Padilla,C; Giacaman,RA;
Revista clínica de periodoncia, implantología y rehabilitación oral , 2011, DOI: 10.4067/S0719-01072011000100002
Abstract: background: streptococcus mutans (s. mutans) is associated with the onset of caries. since root exposure in patients affected by periodontitis leads to higher caries rates, progressively more severe forms of periodontal disease might associate with elevated counts of s. mutans. aim: to determine whether increasingly destructive forms of periodontal disease are associated with higher counts of s. mutans in untreated patients. methods: 206 subjects aged 20-75 were classified into three groups according to the severity of periodontal disease: 1) gingivitis, 2) chronic slight periodontitis and 3) chronic moderate or chronic severe periodontitis. s. mutans counts (cfu/ml) were obtained by direct counting on selective agar plates from saliva samples. a cumulative proportional logistic regression model was adjusted for s. mutans counts. results: the model failed to show differences by gender, but periodontal diagnosis had a significant effect on s. mutans counts depending on age. while in the group with moderate and severe periodontitis the probability of having high counts of s. mutans significantly increased with age, the probability remained unchanged in individuals with chronic slight periodontitis or gingivitis. conclusion: high s. mutans levels appear directly co-associated with increased severity of periodontal disease at older ages in untreated patients.
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