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Jacob Ten M Cate - One of the best experts on this subject based on the ideXlab platform.
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microstructural differences between single species and dual species biofilms of streptococcus mutans and Veillonella parvula before and after exposure to chlorhexidine
Fems Microbiology Letters, 2007Co-Authors: Duygu Kara, S B I Luppens, Jan Van Marle, Rifat Ozok, Jacob Ten M CateAbstract:Dual-species biofilms of Streptococcus mutans and Veillonella parvula are less susceptible to antimicrobials than single-species biofilms of the same microorganisms. The microstructure of single and dual-species biofilms of S. mutans and/or V. parvula was visualized to find out whether the spatial arrangement of bacteria in biofilms is related to survival strategies against antimicrobials. Biofilms were grown in glass-bottomed 96-well microtiter plates and exposed to chlorhexidine at 48 h. Fluorescent probes were used for staining. The microstructure of biofilms was analyzed by confocal scanning laser microscopy at 48, 96, 192, and 264 h. Spatial arrangement analysis was performed using daime software for 48 h biofilms. A decrease in the viability and thickness in all types of biofilms was detected after chlorhexidine treatment in time. In untreated biofilms, clustering was observed. In chlorhexidine-treated single-species biofilms, bacteria were dispersed. However, the most prominent clustering was observed in chlorhexidine-treated dual-species biofilm bacteria, which had a higher survival rate compared with chlorhexidine-treated single-species biofilms. Bacteria in dual-species biofilms establish a specific spatial arrangement, forming clusters within distances below 1.2 μm as a survival strategy against antimicrobials while the same bacteria lack this defensive construction in a single-species biofilm.
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differences between single and dual species biofilms of streptococcus mutans and Veillonella parvula in growth acidogenicity and susceptibility to chlorhexidine
European Journal of Oral Sciences, 2006Co-Authors: Duygu Kara, S B I Luppens, Jacob Ten M CateAbstract:: Streptococcus mutans, considered a primary pathogen in dental caries, thrives in dental plaque, which is a multispecies biofilm. Metabolic interactions between S. mutans and Veillonella parvula have been suggested. In this study we developed a biofilm model to quantify single-species (S. mutans or V. parvula) and dual-species (S. mutans and V. parvula) biofilm formation, and we identified the differences between the respective biofilms in terms of growth, acid formation, and response to chlorhexidine. Polystyrene 96-well microtiter plates were used for biofilm formation. These biofilms were exposed to various chlorhexidine concentrations (0.025-0.4 mg ml(-1)) and treatment conditions. Growth of the biofilms and the effects of chlorhexidine were evaluated by viable counts. Viability of the two species in all biofilm types was similar ( approximately 10(8) colony-forming units per well) after 72 h. Lactic acid accumulation of dual-species biofilms was significantly lower at 48 and 72 h than single-species biofilms of S. mutans. Dual-species biofilms were less susceptible to chlorhexidine than single-species biofilms when a neutralization step was included. These results indicate that bacteria in dual-species biofilms have different properties from bacteria in single-species biofilms.
Michael Frank - One of the best experts on this subject based on the ideXlab platform.
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Veillonella parvula meningitis case report and review of Veillonella infections
Clinical Infectious Diseases, 2000Co-Authors: Maqsood A Bhatti, Michael FrankAbstract:: Veillonella parvula is a small, nonfermentative anaerobic gram-negative coccus that is part of the normal flora of the mouth, gastrointestinal tract, and vagina in humans. When isolated from clinical specimens, V. parvula is often regarded as a contaminant or commensal, but it has been implicated as a pathogen in infections of the sinuses, lungs, heart, bone, and central nervous system. Meningitis, however, is extremely rare; to our knowledge, only 2 cases have been previously described in the literature. We report a case of V. parvula meningitis and review the literature on Veillonella infections.
Duygu Kara - One of the best experts on this subject based on the ideXlab platform.
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effect of Veillonella parvula on the antimicrobial resistance and gene expression of streptococcus mutans grown in a dual species biofilm
Oral Microbiology and Immunology, 2008Co-Authors: S B I Luppens, Duygu Kara, L Bandounas, Martijs J Jonker, Floyd R A Wittink, Oskar Bruning, Timo M Breit, J Ten M Cate, Wim CrielaardAbstract:Introduction: Our previous studies showed that Streptococcus mutans and Veillonella parvula dual-species biofilms have a different acid production profile and a higher resistance to chlorhexidine than their single-species counterparts. The aim of the current study was to test whether the susceptibility of S. mutans grown in the presence of V. parvula is also decreased when it is exposed to various other antimicrobials. Furthermore, the aim was to identify other changes in the physiology of S. mutans when V. parvula was present using transcriptomics. Methods: Susceptibility to antimicrobials was assessed in killing experiments. Transcript levels in S. mutans were measured with the help of S. mutans microarrays. Results: When V. parvula was present, S. mutans showed an increase in survival after exposure to various antimicrobials. Furthermore, this co-existence altered the physiology of S. mutans. The expression of genes coding for proteins involved in amino acid synthesis, the signal recognition particle-translocation pathway, purine metabolism, intracellular polysaccharide synthesis, and protein synthesis all changed. Conclusion: Growing in a biofilm together with a non-pathogenic bacterium like V. parvula changes the physiology of S. mutans, and gives this bacterium an advantage in surviving antimicrobial treatment. Thus, the study of pathogens implicated in polymicrobial diseases, such as caries and periodontitis, should be focused more on multispecies biofilms. In addition, the testing of susceptibility to currently used and new antimicrobials should be performed on a multispecies microbial community rather than with single pathogens.
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microstructural differences between single species and dual species biofilms of streptococcus mutans and Veillonella parvula before and after exposure to chlorhexidine
Fems Microbiology Letters, 2007Co-Authors: Duygu Kara, S B I Luppens, Jan Van Marle, Rifat Ozok, Jacob Ten M CateAbstract:Dual-species biofilms of Streptococcus mutans and Veillonella parvula are less susceptible to antimicrobials than single-species biofilms of the same microorganisms. The microstructure of single and dual-species biofilms of S. mutans and/or V. parvula was visualized to find out whether the spatial arrangement of bacteria in biofilms is related to survival strategies against antimicrobials. Biofilms were grown in glass-bottomed 96-well microtiter plates and exposed to chlorhexidine at 48 h. Fluorescent probes were used for staining. The microstructure of biofilms was analyzed by confocal scanning laser microscopy at 48, 96, 192, and 264 h. Spatial arrangement analysis was performed using daime software for 48 h biofilms. A decrease in the viability and thickness in all types of biofilms was detected after chlorhexidine treatment in time. In untreated biofilms, clustering was observed. In chlorhexidine-treated single-species biofilms, bacteria were dispersed. However, the most prominent clustering was observed in chlorhexidine-treated dual-species biofilm bacteria, which had a higher survival rate compared with chlorhexidine-treated single-species biofilms. Bacteria in dual-species biofilms establish a specific spatial arrangement, forming clusters within distances below 1.2 μm as a survival strategy against antimicrobials while the same bacteria lack this defensive construction in a single-species biofilm.
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differences between single and dual species biofilms of streptococcus mutans and Veillonella parvula in growth acidogenicity and susceptibility to chlorhexidine
European Journal of Oral Sciences, 2006Co-Authors: Duygu Kara, S B I Luppens, Jacob Ten M CateAbstract:: Streptococcus mutans, considered a primary pathogen in dental caries, thrives in dental plaque, which is a multispecies biofilm. Metabolic interactions between S. mutans and Veillonella parvula have been suggested. In this study we developed a biofilm model to quantify single-species (S. mutans or V. parvula) and dual-species (S. mutans and V. parvula) biofilm formation, and we identified the differences between the respective biofilms in terms of growth, acid formation, and response to chlorhexidine. Polystyrene 96-well microtiter plates were used for biofilm formation. These biofilms were exposed to various chlorhexidine concentrations (0.025-0.4 mg ml(-1)) and treatment conditions. Growth of the biofilms and the effects of chlorhexidine were evaluated by viable counts. Viability of the two species in all biofilm types was similar ( approximately 10(8) colony-forming units per well) after 72 h. Lactic acid accumulation of dual-species biofilms was significantly lower at 48 and 72 h than single-species biofilms of S. mutans. Dual-species biofilms were less susceptible to chlorhexidine than single-species biofilms when a neutralization step was included. These results indicate that bacteria in dual-species biofilms have different properties from bacteria in single-species biofilms.
Sam Pitluck - One of the best experts on this subject based on the ideXlab platform.
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complete genome sequence of Veillonella parvula type strain te3 t
Standards in Genomic Sciences, 2010Co-Authors: Sabine Gronow, Sabine Welnitz, Alla Lapidus, Matt Nolan, Natalia Ivanova, Alex Copeland, Feng Chen, Hope Tice, Sam Pitluck, Jan Fang ChengAbstract:Veillonella parvula (Veillon and Zuber 1898) Prevot 1933 is the type species of the genus Veillonella in the family Veillonellaceae within the order Clostridiales. The species V. parvula is of interest because it is frequently isolated from dental plaque in the human oral cavity and can cause opportunistic infections. The species is strictly anaerobic and grows as small cocci which usually occur in pairs. Veillonellae are characterized by their unusual metabolism which is centered on the activity of the enzyme methylmalonyl-CoA decarboxylase. Strain Te3T, the type strain of the species, was isolated from the human intestinal tract. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the large clostridial family Veillonellaceae, and the 2,132,142 bp long single replicon genome with its 1,859 protein-coding and 61 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.
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Complete genome sequence of Veillonella parvula type strain (Te3^T)
Standards in Genomic Sciences, 2010Co-Authors: Sabine Gronow, Sabine Welnitz, Alla Lapidus, Matt Nolan, Natalia Ivanova, Tijana Glavina Del Rio, Alex Copeland, Feng Chen, Hope Tice, Sam PitluckAbstract:Veillonella parvula (Veillon and Zuber 1898) Prévot 1933 is the type species of the genus Veillonella in the family Veillonellaceae within the order Clostridiales . The species V. parvula is of interest because it is frequently isolated from dental plaque in the human oral cavity and can cause opportunistic infections. The species is strictly anaerobic and grows as small cocci which usually occur in pairs. Veillonellae are characterized by their unusual metabolism which is centered on the activity of the enzyme methylmalonyl-CoA decarboxylase. Strain Te3^T, the type strain of the species, was isolated from the human intestinal tract. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the large clostridial family Veillonellaceae , and the 2,132,142 bp long single replicon genome with its 1,859 protein-coding and 61 RNA genes is part of the G enomic E ncyclopedia of B acteria and A rchaea project.
Maqsood A Bhatti - One of the best experts on this subject based on the ideXlab platform.
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Veillonella parvula meningitis case report and review of Veillonella infections
Clinical Infectious Diseases, 2000Co-Authors: Maqsood A Bhatti, Michael FrankAbstract:: Veillonella parvula is a small, nonfermentative anaerobic gram-negative coccus that is part of the normal flora of the mouth, gastrointestinal tract, and vagina in humans. When isolated from clinical specimens, V. parvula is often regarded as a contaminant or commensal, but it has been implicated as a pathogen in infections of the sinuses, lungs, heart, bone, and central nervous system. Meningitis, however, is extremely rare; to our knowledge, only 2 cases have been previously described in the literature. We report a case of V. parvula meningitis and review the literature on Veillonella infections.