Amino Sugars Modify Antagonistic Interactions between Commensal Oral Streptococci andStreptococcus mutans

ABSTRACTN-acetylglucosamine (GlcNAc) and glucosamine (GlcN) enhance the competitiveness of the laboratory strain DL1 ofStreptococcus gordoniiagainst the caries pathogenStreptococcus mutans. Here we examine how amino sugars affect the interaction of five low-passage clinical isolates of abundant commensal streptococci withS. mutansutilizing a dual-species biofilm model. Compared to glucose, growth on GlcN or GlcNAc significantly reduced the viability ofS. mutansin co-cultures with most commensals, shifting the proportions of species. Consistent with these results, production of H2O2was increased in most commensals when growing on amino sugars, and inhibition ofS. mutansbyStreptococcus cristatus, Streptococcus oralis,orS. gordoniiwas enhanced by amino sugars on agar plates. All commensals exceptS. oralishad higher arginine deiminase activities when grown on GlcN, and in some cases GlcNAc. Inex vivobiofilms formed using pooled cell-containing saliva (CCS), the proportions ofS. mutanswere drastically diminished when GlcNAc was the primary carbohydrate. Increased production of H2O2could account in large part for the inhibitory effects of CCS biofilms. Surprisingly, amino sugars appeared to improve mutacin production byS. mutanson agar plates, suggesting that the commensals have mechanisms to actively subvert antagonism byS. mutansin co-cultures. Collectively, these findings demonstrate that amino sugars can enhance the beneficial properties of low-passage commensal oral streptococci and highlight their potential for moderating the cariogenicity of oral biofilms.SIGNIFICANCEDental caries is driven by dysbiosis of oral biofilms in which dominance by acid-producing and acid-tolerant bacteria results in loss of tooth mineral. Our previous work demonstrated the beneficial effects of amino sugars, GlcNAc and GlcN, in promoting the antagonistic properties of a health-associated oral bacterium,Streptococcus gordonii,in competition with the major caries pathogenStreptococcus mutans.Here we investigated 5 low-passage clinical isolates of the most common streptococcal species to establish how amino sugars may influence the ecology and virulence of oral biofilms. Using multiplein vitromodels, including a human saliva-derived microcosm biofilm, experiments showed significant enhancement by at least one amino sugar in the ability of most of these bacteria to suppress the caries pathogen. Therefore, our findings demonstrated the mechanism of action by which amino sugars may affect human oral biofilms to promote health.

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Amino Sugars Modify Antagonistic Interactions between Commensal Oral Streptococci andStreptococcus mutans

Applied and Environmental Microbiology ◽

10.1128/aem.00370-19 ◽

2019 ◽

Vol 85 (10) ◽

Cited By ~ 7

Author(s):

Lulu Chen ◽

Brinta Chakraborty ◽

Jing Zou ◽

Robert A. Burne ◽

Lin Zeng

Keyword(s):

Streptococcus Mutans ◽

Arginine Deiminase ◽

Clinical Isolates ◽

Amino Sugars ◽

Oral Streptococci ◽

Streptococcus Gordonii ◽

Content Type ◽

Oral Biofilms ◽

Passage Number ◽

Low Passage

ABSTRACTN-Acetylglucosamine (GlcNAc) and glucosamine (GlcN) enhance the competitiveness of the laboratory strain DL1 ofStreptococcus gordoniiagainst the caries pathogenStreptococcus mutans. Here, we examine how amino sugars affect the interaction of five low-passage-number clinical isolates of abundant commensal streptococci withS. mutansby utilizing a dual-species biofilm model. Compared to that for glucose, growth on GlcN or GlcNAc significantly reduced the viability ofS. mutansin cocultures with most commensals, shifting the proportions of species. Consistent with these results, production of H2O2was increased in most commensals when growing on amino sugars, and inhibition ofS. mutansbyStreptococcus cristatus,Streptococcus oralis, orS. gordoniiwas enhanced by amino sugars on agar plates. All commensals exceptS. oralishad higher arginine deiminase activities when grown on GlcN and, in some cases, GlcNAc. Inex vivobiofilms formed using pooled cell-containing saliva (CCS), the proportions ofS. mutanswere drastically diminished when GlcNAc was the primary carbohydrate. Increased production of H2O2could account in large part for the inhibitory effects of CCS biofilms. Surprisingly, amino sugars appeared to improve mutacin production byS. mutanson agar plates, suggesting that the commensals have mechanisms to actively subvert antagonism byS. mutansin cocultures. Collectively, these findings demonstrate that amino sugars can enhance the beneficial properties of low-passage-number commensal oral streptococci and highlight their potential for moderating the cariogenicity of oral biofilms.IMPORTANCEDental caries is driven by dysbiosis of oral biofilms in which dominance by acid-producing and acid-tolerant bacteria results in loss of tooth mineral. Our previous work demonstrated the beneficial effects of amino sugars GlcNAc and GlcN in promoting the antagonistic properties of a health-associated oral bacterium,Streptococcus gordonii, in competition with the major caries pathogenStreptococcus mutans. Here, we investigated 5 low-passage-number clinical isolates of the most common streptococcal species to establish how amino sugars may influence the ecology and virulence of oral biofilms. Using multiplein vitromodels, including a human saliva-derived microcosm biofilm, experiments showed significant enhancement by at least one amino sugar in the ability of most of these bacteria to suppress the caries pathogen. Therefore, our findings demonstrated the mechanism of action by which amino sugars may affect human oral biofilms to promote health.

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Streptococcal Antagonism in Oral Biofilms: Streptococcus sanguinis and Streptococcus gordonii Interference with Streptococcus mutans

Journal of Bacteriology ◽

10.1128/jb.00276-08 ◽

2008 ◽

Vol 190 (13) ◽

pp. 4632-4640 ◽

Cited By ~ 249

Author(s):

Jens Kreth ◽

Yongshu Zhang ◽

Mark C. Herzberg

Keyword(s):

Streptococcus Mutans ◽

Bacterial Species ◽

Ecological Factors ◽

Oral Streptococci ◽

Streptococcus Gordonii ◽

Interspecies Interactions ◽

Streptococcus Sanguinis ◽

Production Of Hydrogen ◽

Oral Biofilms ◽

Competence System

ABSTRACT Biofilms are polymicrobial, with diverse bacterial species competing for limited space and nutrients. Under healthy conditions, the different species in biofilms maintain an ecological balance. This balance can be disturbed by environmental factors and interspecies interactions. These perturbations can enable dominant growth of certain species, leading to disease. To model clinically relevant interspecies antagonism, we studied three well-characterized and closely related oral species, Streptococcus gordonii, Streptococcus sanguinis, and cariogenic Streptococcus mutans. S. sanguinis and S. gordonii used oxygen availability and the differential production of hydrogen peroxide (H2O2) to compete effectively against S. mutans. Interspecies antagonism was influenced by glucose with reduced production of H2O2. Furthermore, aerobic conditions stimulated the competence system and the expression of the bacteriocin mutacin IV of S. mutans, as well as the H2O2-dependent release of heterologous DNA from mixed cultures of S. sanguinis and S. gordonii. These data provide new insights into ecological factors that determine the outcome of competition between pioneer colonizing oral streptococci and the survival mechanisms of S. mutans in the oral biofilm.

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Amino Sugars Enhance the Competitiveness of Beneficial Commensals with Streptococcus mutans through Multiple Mechanisms

Applied and Environmental Microbiology ◽

10.1128/aem.00637-16 ◽

2016 ◽

Vol 82 (12) ◽

pp. 3671-3682 ◽

Cited By ~ 17

Author(s):

Lin Zeng ◽

Tanaz Farivar ◽

Robert A. Burne

Keyword(s):

Dental Caries ◽

Streptococcus Mutans ◽

Sugar Metabolism ◽

Amino Sugar ◽

Amino Sugars ◽

Mrna Levels ◽

Oral Streptococci ◽

Streptococcus Gordonii ◽

Carbohydrate Source ◽

Content Type

ABSTRACTBiochemical and genetic aspects of the metabolism of the amino sugarsN-acetylglucosamine (GlcNAc) and glucosamine (GlcN) by commensal oral streptococci and the effects of these sugars on interspecies competition with the dental caries pathogenStreptococcus mutanswere explored. MultipleS. mutanswild-type isolates displayed long lag phases when transferred from glucose-containing medium to medium with GlcNAc as the primary carbohydrate source, but commensal streptococci did not. Competition in liquid coculture or dual-species biofilms betweenS. mutansandStreptococcus gordoniishowed thatS. gordoniiwas particularly dominant when the primary carbohydrate was GlcN or GlcNAc. Transcriptional and enzymatic assays showed that the catabolic pathway for GlcNAc was less highly induced inS. mutansthan inS. gordonii. Exposure to H2O2, which is produced byS. gordoniiand antagonizes the growth ofS. mutans, led to reduced mRNA levels ofnagAandnagBinS. mutans. When the gene for the transcriptional regulatory NagR was deleted inS. gordonii, the strain produced constitutively high levels ofnagA(GlcNAc-6-P deacetylase),nagB(GlcN-6-P deaminase), andglmS(GlcN-6-P synthase) mRNA. Similar to NagR ofS. mutans(NagRSm), theS. gordoniiNagR protein (NagRSg) could bind to consensus binding sites (dre) in thenagA,nagB, andglmSpromoter regions ofS. gordonii. Notably, NagRSgbinding was inhibited by GlcN-6-P, but G-6-P had no effect, unlike for NagRSm. This study expands the understanding of amino sugar metabolism and NagR-dependent gene regulation in streptococci and highlights the potential for therapeutic applications of amino sugars to prevent dental caries.IMPORTANCEAmino sugars are abundant in the biosphere, so the relative efficiency of particular bacteria in a given microbiota to metabolize these sources of carbon and nitrogen might have a profound impact on the ecology of the community. Our investigation reveals that several oral commensal bacteria have a much greater capacity to utilize amino sugars than the dental pathogenStreptococcus mutansand that the ability of the model commensalStreptococcus gordoniito compete againstS. mutansis substantively enhanced by the presence of amino sugars commonly found in the oral cavity. The mechanisms underlying the greater capacity and competitive enhancements of the commensal are shown to depend on how the genes for the catabolic enzymes are regulated, the role of the allosteric modulators affecting such regulation, and the ability of amino sugars to enhance certain activities of the commensal that are antagonistic toS. mutans.

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In Vivo Colonization with Candidate Oral Probiotics Attenuates Colonization and Virulence of Streptococcus mutans

Applied and Environmental Microbiology ◽

10.1128/aem.02490-20 ◽

2020 ◽

Author(s):

David. J. Culp ◽

William Hull ◽

Matthew J. Bremgartner ◽

Todd A. Atherly ◽

Kacey N. Christian ◽

...

Keyword(s):

Dental Caries ◽

Mouse Model ◽

Streptococcus Mutans ◽

Arginine Deiminase ◽

Oral Streptococci ◽

Study Results ◽

Autochthonous Bacteria ◽

High Sucrose

A collection of 113 Streptococcus strains from supragingival dental plaque of caries-free individuals were recently tested in vitro for direct antagonism of the dental caries pathogen Streptococcus mutans, and for their capacity for arginine catabolism via the arginine deiminase system (ADS). To advance their evaluation as potential probiotics, twelve strains of commensal oral streptococci with various antagonistic and ADS potentials were assessed in a mouse model for oral (i.e., oral mucosal pellicles and saliva) and dental colonization under four diets (healthy or high-sucrose, with or without prebiotic arginine). Colonization by autochthonous bacteria was also monitored. One strain failed to colonize, whereas oral colonization by the other eleven strains varied by 3 log units. Dental colonization was high for five strains regardless of diet, six strains increased colonization with at least one high-sucrose diet, and added dietary arginine decreased dental colonization of two strains. Streptococcus sp. A12 (high in vitro ADS activity and antagonism) and two engineered mutants lacking the ADS (ΔarcADS) or pyruvate oxidase-mediated H2O2 production (ΔspxB) were tested for competition against S. mutans UA159. A12 wild type and ΔarcADS colonized only transiently, whereas ΔspxB persisted, but without altering oral or dental colonization by S. mutans. In testing four additional candidates, S. sanguinis BCC23 markedly attenuated S. mutans’ oral and dental colonization, enhanced colonization of autochthonous bacteria, and decreased severity of smooth surface caries under highly cariogenic conditions. Results demonstrate the utility of the mouse model to evaluate potential probiotics, revealing little correlation between in vitro antagonism and competitiveness against S. mutans in vivo. IMPORTANCE Our results demonstrate in vivo testing of potential oral probiotics can be accomplished and can yield information to facilitate the ultimate design and optimization of novel anti-caries probiotics. We show human oral commensals associated with dental health are an important source of potential probiotics that may be used to colonize patients under dietary conditions of highly varying cariogenicity. Assessment of competitiveness against dental caries pathogen Streptococcus mutans and impact on caries identified strains or genetic elements for further study. Results also uncovered strains that enhanced oral and dental colonization by autochthonous bacteria when challenged with S. mutans, suggesting cooperative interactions for future elucidation. Distinguishing a rare strain that effectively compete with S. mutans under conditions that promote caries further validates our systematic approach to more critically evaluate probiotics for use in humans.

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Function-adaptive clustered nanoparticles reverse Streptococcus mutans dental biofilm and maintain microbiota balance

Communications Biology ◽

10.1038/s42003-021-02372-y ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Fatemeh Ostadhossein ◽

Parikshit Moitra ◽

Esra Altun ◽

Debapriya Dutta ◽

Dinabandhu Sar ◽

...

Keyword(s):

Streptococcus Mutans ◽

Ex Vivo ◽

Bacterial Species ◽

Reactive Oxygen Species Generation ◽

Biofilm Inhibition ◽

16S Rrna Analysis ◽

Dental Biofilm ◽

Dental Plaques

AbstractDental plaques are biofilms that cause dental caries by demineralization with acidogenic bacteria. These bacteria reside inside a protective sheath which makes any curative treatment challenging. We propose an antibiotic-free strategy to disrupt the biofilm by engineered clustered carbon dot nanoparticles that function in the acidic environment of the biofilms. In vitro and ex vivo studies on the mature biofilms of Streptococcus mutans revealed >90% biofilm inhibition associated with the contact-mediated interaction of nanoparticles with the bacterial membrane, excessive reactive oxygen species generation, and DNA fragmentation. An in vivo examination showed that these nanoparticles could effectively suppress the growth of S. mutans. Importantly, 16S rRNA analysis of the dental microbiota showed that the diversity and richness of bacterial species did not substantially change with nanoparticle treatment. Overall, this study presents a safe and effective approach to decrease the dental biofilm formation without disrupting the ecological balance of the oral cavity.

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Amino Sugars Reshape Interactions between Streptococcus mutans and Streptococcus gordonii

Applied and Environmental Microbiology ◽

10.1128/aem.01459-20 ◽

2020 ◽

Vol 87 (1) ◽

Author(s):

Lulu Chen ◽

Alejandro R. Walker ◽

Robert A. Burne ◽

Lin Zeng

Keyword(s):

Gene Expression ◽

Streptococcus Mutans ◽

Single Species ◽

Oral Bacteria ◽

Amino Sugars ◽

Sequencing Analysis ◽

Streptococcus Gordonii ◽

Bacterial Gene ◽

Content Type ◽

The Impact

ABSTRACT Amino sugars, particularly glucosamine (GlcN) and N-acetylglucosamine (GlcNAc), are abundant carbon and nitrogen sources supplied in host secretions and in the diet to the biofilms colonizing the human oral cavity. Evidence is emerging that these amino sugars provide ecological advantages to beneficial commensals over oral pathogens and pathobionts. Here, we performed transcriptome analysis on Streptococcus mutans and Streptococcus gordonii growing in single-species or dual-species cultures with glucose, GlcN, or GlcNAc as the primary carbohydrate source. Compared to glucose, GlcN caused drastic transcriptomic shifts in each species of bacteria when it was cultured alone. Likewise, cocultivation in the presence of GlcN yielded transcriptomic profiles that were dramatically different from the single-species results from GlcN-grown cells. In contrast, GlcNAc elicited only minor changes in the transcriptome of either organism in single- and dual-species cultures. Interestingly, genes involved in pyruvate metabolism were among the most significantly affected by GlcN in both species, and these changes were consistent with measurements of pyruvate in culture supernatants. Differing from what was found in a previous report, growth of S. mutans alone with GlcN inhibited the expression of multiple operons required for mutacin production. Cocultivation with S. gordonii consistently increased the expression of two manganese transporter operons (slo and mntH) and decreased expression of mutacin genes in S. mutans. Conversely, S. gordonii appeared to be less affected by the presence of S. mutans but did show increases in genes for biosynthetic processes in the cocultures. In conclusion, amino sugars profoundly alter the interactions between pathogenic and commensal streptococci by reprogramming central metabolism. IMPORTANCE Carbohydrate metabolism is central to the development of dental caries. A variety of sugars available to dental microorganisms influence the development of caries by affecting the physiology, ecology, and pathogenic potential of tooth biofilms. Using two well-characterized oral bacteria, one pathogen (Streptococcus mutans) and one commensal (Streptococcus gordonii), in an RNA deep-sequencing analysis, we studied the impact of two abundant amino sugars on bacterial gene expression and interspecies interactions. The results indicated large-scale remodeling of gene expression induced by GlcN in particular, affecting bacterial energy generation, acid production, protein synthesis, and release of antimicrobial molecules. Our study provides novel insights into how amino sugars modify bacterial behavior, information that will be valuable in the design of new technologies to detect and prevent oral infectious diseases.

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Streptococcus gordonii Hsa Environmentally Constrains Competitive Binding by Streptococcus sanguinis to Saliva-Coated Hydroxyapatite

Journal of Bacteriology ◽

10.1128/jb.01535-06 ◽

2007 ◽

Vol 189 (8) ◽

pp. 3106-3114 ◽

Cited By ~ 36

Author(s):

Angela H. Nobbs ◽

Yongshu Zhang ◽

Ali Khammanivong ◽

Mark C. Herzberg

Keyword(s):

Selective Advantage ◽

Competitive Binding ◽

Tooth Surface ◽

Oral Streptococci ◽

Streptococcus Gordonii ◽

Streptococcus Sanguinis ◽

Competitive Capabilities ◽

Vitro Model ◽

Isogenic Mutants

ABSTRACT Competition between pioneer colonizing bacteria may determine polymicrobial succession during dental plaque development, but the ecological constraints are poorly understood. For example, more Streptococcus sanguinis than Streptococcus gordonii organisms are consistently isolated from the same intraoral sites, yet S. gordonii fails to be excluded and survives as a species over time. To explain this observation, we hypothesized that S. gordonii could compete with S. sanguinis to adhere to saliva-coated hydroxyapatite (sHA), an in vitro model of the tooth surface. Both species bound similarly to sHA, yet 10- to 50-fold excess S. gordonii DL1 reduced binding of S. sanguinis SK36 by 85 to >95%. S. sanguinis, by contrast, did not significantly compete with S. gordonii to adhere. S. gordonii competed with S. sanguinis more effectively than other species of oral streptococci and depended upon the salivary film on HA. Next, putative S. gordonii adhesins were analyzed for contributions to interspecies competitive binding. Like wild-type S. gordonii, isogenic mutants with mutations in antigen I/II polypeptides (sspAB), amylase-binding proteins (abpAB), and Csh adhesins (cshAB) competed effectively against S. sanguinis. By contrast, an hsa-deficient mutant of S. gordonii showed significantly reduced binding and competitive capabilities, while these properties were restored in an hsa-complemented strain. Thus, Hsa confers a selective advantage to S. gordonii over S. sanguinis in competitive binding to sHA. Hsa expression may, therefore, serve as an environmental constraint against S. sanguinis, enabling S. gordonii to persist within the oral cavity, despite the greater natural prevalence of S. sanguinis in plaque and saliva.

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ACTIVITY OF PERICARP EXTRACT OF MANGOSTEEN AGAINST ORAL STREPTOCOCCI

Dentika Dental Journal ◽

10.32734/dentika.v20i1.739 ◽

2017 ◽

Vol 20 (1) ◽

pp. 41-46

Author(s):

Dewi Nurul Mustaqimah ◽

Josh Erry HW

Keyword(s):

Antimicrobial Activity ◽

Dental Caries ◽

Streptococcus Mutans ◽

Antimicrobial Agents ◽

Biological Activities ◽

World Health ◽

Direct Result ◽

Oral Streptococci ◽

Oral Pathogens

The increasing prevalence of dental caries is still as a major world health problem. Caries is the direct result of acid production by cariogenic oral pathogens, especially Streptococcus mutans. New and better antimicrobial agents active against cariogenic bacteria with minimal side effects on the oral tissues are much needed, especially natural agents derived directly from plants. Phytochemical studies have shown that the extracts from various parts of mangosteen or Garciniamangostana Linn tree contain varieties of secondary metabolites such as prenylated and oxygenated xanthones, many of which have been found in vitro to have antimicrobial properties against oral pathogens. Several studies which examined the eficacy of herbal for human health have shown that xanthones from mangosteen have remarkable biological activities such as antioxidant, antimicrobial, anticancer etc, and had no cytotoxic effects on human gingival fibroblasts. Their results showed that among these xanthone derivatives obtain from pericarp extract of mangosteen, α-mangostin has the most potent antimicrobial activity against cariogenic Streptococcus mutans. It can be concluded that the strong antimicrobial activity of the pericarp extract of mangosteen is a good drug of choice that might be helpful in preventing the dental caries.

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Ex VivoActivity of Histone Deacetylase Inhibitors against Multidrug-Resistant Clinical Isolates ofPlasmodium falciparumandP. vivax

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01220-10 ◽

2010 ◽

Vol 55 (3) ◽

pp. 961-966 ◽

Cited By ~ 33

Author(s):

Jutta Marfurt ◽

Ferryanto Chalfein ◽

Pak Prayoga ◽

Frans Wabiser ◽

Enny Kenangalem ◽

...

Keyword(s):

Histone Deacetylase ◽

Histone Deacetylase Inhibitors ◽

Ex Vivo ◽

Hdac Inhibitors ◽

Multidrug Resistant ◽

Clinical Isolates ◽

Antimalarial Therapy ◽

Susceptibility Profiles ◽

Antimalarial Compounds

ABSTRACTHistone acetylation plays an important role in regulating gene transcription and silencing inPlasmodium falciparum. Histone deacetylase (HDAC) inhibitors, particularly those of the hydroxamate class, have been shown to have potentin vitroactivity against drug-resistant and -sensitive laboratory strains ofP. falciparum, raising their potential as a new class of antimalarial compounds. In the current study, stage-specificex vivosusceptibility profiles of representative hydroxamate-based HDAC inhibitors suberoylanilide hydroxamic acid (SAHA), 2-ASA-9, and 2-ASA-14 (2-ASA-9 and 2-ASA-14 are 2-aminosuberic acid-based HDAC inhibitors) were assessed in multidrug-resistant clinical isolates ofP. falciparum(n= 24) andP. vivax(n= 25) from Papua, Indonesia, using a modified schizont maturation assay. Submicromolar concentrations of SAHA, 2-ASA-9, and 2-ASA-14 inhibited the growth of bothP. falciparum(median 50% inhibitory concentrations [IC50s] of 310, 533, and 266 nM) andP. vivax(median IC50s of 170, 503, and 278 nM). Inverse correlation patterns between HDAC inhibitors and chloroquine forP. falciparumand mefloquine forP. vivaxindicate species-specific susceptibility profiles for HDAC inhibitors. These HDAC inhibitors were also found to be potentex vivoagainstP.vivaxschizont maturation, comparable to that inP. falciparum, suggesting that HDAC inhibitors may be promising candidates for antimalarial therapy in geographical locations where both species are endemic. Further studies optimizing the selectivity andin vivoefficacy of HDAC inhibitors inPlasmodiumspp. and defining drug interaction with common antimalarial compounds are warranted to investigate the role of HDAC inhibitors in antimalarial therapy.

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