Veillonella faecalis sp. nov., a propionic acid-producing bacterium isolated from the faeces of an infant.

A strictly anaerobic, Gram-stain-negative, catalase-negative, cocci-shaped, and propionate-producing bacterial strain, named Ds1651T was isolated from the fecal sample collected from a South Korean infant. Through a comparison of 16S rRNA gene sequences, it was revealed that Ds1651T had the highest phylogenetic affinity with Veillonella nakazawae KCTC 25297 T (99.86%), followed by Veillonella infantium KCTC 25370 T (99.80%), and Veillonella dispar KCTC 25309 T (99.73%) in the family Veillonellaceae. Average nucleotide identity values between Ds1651T and three reference species were 95.48% for Veillonella nakazawae KCTC 25297 T, 94.46% for Veillonella infantium KCTC 25370 T, and 92.81% for Veillonella dispar KCTC 25309 T. The G + C content of Ds1651T was 38.58 mol%. Major fermentation end-products were acetic and propionic acids in Trypticase peptone glucose yeast extract broth with 1% (v/v) sodium lactate. The predominant cellular fatty acids that account for more than 10% were summed in Feature 8 (C17:1 ω8c and/or C17:2) and C13:0. Based on the findings from phylogenetic, genomic, phenotypic, and chemotaxonomic studies, we propose that the type strain Ds1651T (= KCTC 25477 T = GDMCC 1.3707 T) represents a novel bacterial species within the genus Veillonella, with the proposed name Veillonella faecalis sp. nov.

Lipopolysaccharide-producing Veillonella infantium and Escherichia fergusonii cause vagus nerve-mediated cognitive impairment in mice.

Gut microbiota communicates bidirectionally with the brain through the nervous, immune, and endocrine systems of the gut. In our preliminary study, the fecal microbiota of volunteers with mild cognitive impairment (Fmci) exhibited a higher abundance of Escherichia fergusonii (NK2001), Veillonella infantium (NK2002), and Enterococcus faecium (NK2003) populations compared with those of healthy volunteers. Therefore, we examined the effects of Fmci, NK2001 (gram-negative), NK2002 (gram-negative-like), and NK2003 (gram-positive) on cognitive impairment-like behavior, neuroinflammation, and colitis in mice with or without antibiotics. Fmci transplantation increased cognitive impairment-like behavior, hippocampal tumor necrosis factor (TNF)-α expression, and the size of toll-like receptor (TLR)4+Iba1+, TLR2+Iba1+, and NF-κB+Iba1+ cell populations independent of antibiotic treatment. Oral gavage of NK2001, NK2002, or NK2003, which induced TNF-α expression in Caco-2 cells, significantly increased cognitive impairment-like behavior and hippocampal TNF-α expression and Iba1-positive cell populations and decreased brain-derived neurotrophic factor (BDNF) expression in mice. Celiac vagotomy significantly decreased NK2001- or NK2002-induced cognitive impairment-like behavior and hippocampal Iba1+ cell population and TNF-α expression and increased NK2001- or NK2002-suppressed hippocampal BDNF expression. However, NK2003-induced cognitive impairment-like behavior and hippocampal Iba1+ cell population and TNF-α expression were partially, but not significantly, attenuated by celiac vagotomy. Furthermore, celiac vagotomy did not affect NK2001-, NK2002-, or NK2003-induced lipopolysaccharide (LPS) levels in the blood and feces and TNF-α expression and NF-κB-positive cell population in the colon. In conclusion, LPS-producing NK2001 and NK2002 and LPS-nonproducing NK2003 may induce NF-κB-mediated neuroinflammation through the translocation of byproducts such as LPS and peptidoglycan into the brain through gut-blood/vagus nerve-brain and gut-blood-brain pathways, respectively, resulting in cognitive impairment.

Bacteroidaceae, Bacteroides, and Veillonella: emerging protectors against Graves' disease.

Background: Graves' disease (GD) is the most common cause of hyperthyroidism, and its pathogenesis remains incompletely elucidated. Numerous studies have implicated the gut microbiota in the development of thyroid disorders. This study employs Mendelian randomization analysis to investigate the characteristics of gut microbiota in GD patients, aiming to offer novel insights into the etiology and treatment of Graves' disease. Methods: Two-sample Mendelian randomization (MR) analysis was employed to assess the causal relationship between Graves' disease and the gut microbiota composition. Gut microbiota data were sourced from the international consortium MiBioGen, while Graves' disease data were obtained from FINNGEN. Eligible single nucleotide polymorphisms (SNPs) were selected as instrumental variables. Multiple analysis methods, including inverse variance-weighted (IVW), MR-Egger regression, weighted median, weighted mode, and MR-RAPS, were utilized. Sensitivity analyses were conducted employing MR-Egger intercept test, Cochran's Q test, and leave-one-out analysis as quality control measures. Results: The Mendelian randomization study conducted in a European population revealed a decreased risk of Graves' disease associated with Bacteroidaceae (Odds ratio (OR) [95% confidence interval (CI)]: 0.89 [0.89 ~ 0.90], adjusted P value: <0.001), Bacteroides (OR: [95% CI]: 0.555 [0.437 ~ 0.706], adjusted P value: <0.001), and Veillonella (OR [95% CI]: 0.632 [0.492 ~ 0.811], adjusted P value: 0.016). No significant evidence of heterogeneity, or horizontal pleiotropy was detected. Furthermore, the preliminary MR analysis identified 13 bacterial species including Eubacterium brachy group and Family XIII AD3011 group, exhibiting significant associations with Graves' disease onset, suggesting potential causal effects. Conclusion: A causal relationship exists between gut microbiota and Graves' disease. Bacteroidaceae, Bacteroides, and Veillonella emerge as protective factors against Graves' disease development. Prospective probiotic supplementation may offer a novel avenue for adjunctive treatment in the management of Graves' disease in the future.

Deciphering the Chemical Language of the Immunomodulatory Properties of Veillonella parvula Lipopolysaccharide.

Veillonella parvula, prototypical member of the oral and gut microbiota, is at times commensal yet also potentially pathogenic. The definition of the molecular basis tailoring this contrasting behavior is key for broadening our understanding of the microbiota-driven pathogenic and/or tolerogenic mechanisms that take place within our body. In this study, we focused on the chemistry of the main constituent of the outer membrane of V. parvula, the lipopolysaccharide (LPS). LPS molecules indeed elicit pro-inflammatory and immunomodulatory responses depending on their chemical structures. Herein we report the structural elucidation of the LPS from two strains of V. parvula and show important and unprecedented differences in both the lipid and carbohydrate moieties, including the identification of a novel galactofuranose and mannitol-containing O-antigen repeating unit for one of the two strains. Furthermore, by harnessing computational studies, in vitro human cell models, as well as lectin binding solid-phase assays, we discovered that the two chemically diverse LPS immunologically behave differently and have attempted to identify the molecular determinant(s) governing this phenomenon. Whereas pro-inflammatory potential has been evidenced for the lipid A moiety, by contrast a plausible "immune modulating" action has been proposed for the peculiar O-antigen portion.

Detecting and quantifying Veillonella by real-time quantitative PCR and droplet digital PCR.

Veillonella spp. are Gram-negative opportunistic pathogens present in the respiratory, digestive, and reproductive tracts of mammals. An abnormal increase in Veillonella relative abundance in the body is closely associated with periodontitis, inflammatory bowel disease, urinary tract infections, and many other diseases. We designed a pair of primers and a probe based on the 16S rRNA gene sequences of Veillonella and conducted real-time quantitative PCR (qPCR) and droplet digital PCR (ddPCR) to quantify the abundance of Veillonella in fecal samples. These two methods were tested for specificity and sensitivity using simulated clinical samples. The sensitivity of qPCR was 100 copies/µL, allowing for the accurate detection of a wide range of Veillonella concentrations from 103 to 108 CFU/mL. The sensitivity of ddPCR was 11.3 copies/µL, only allowing for the accurate detection of Veillonella concentrations from 101 to 104 CFU/mL because of the limited number of droplets generated by ddPCR. ddPCR is therefore more suitable for the detection of low-abundance Veillonella samples. To characterize the validity of the assay system, clinical samples from children with inflammatory bowel disease were collected and analyzed, and the results were verified using isolation methods. We conclude that molecular assays targeting the 16S rRNA gene provides an important tool for the rapid diagnosis of chronic and infectious diseases caused by Veillonella and also supports the isolation and identification of Veillonella for research purposes. KEY POINTS: • With suitable primer sets, the qPCR has a wider detection range than ddPCR. • ddPCR is suitable for the detection of low-abundance samples. • Methods successfully guided the isolation of Veillonella in clinical sample.

Splenectomy ameliorates liver cirrhosis by restoring the gut microbiota balance.

BACKGROUND: Dysbiosis of gut microbiota is frequent in liver cirrhosis (LC) patients, and splenectomy (SP) has been reported to improve LC. Herein, we report the effects of SP on gut microbiota, especially on Veillonella parvula, a Gram-negative coccus of the gastrointestinal tract, in LC mice, and the underlying mechanism. METHODS: LC mice models were induced by tail vein injection of concanavalin A (ConA), followed by SP. 16 s rRNA sequencing was conducted to analyze the effects of ConA induction and SP on mouse gut microbiota and the gene expression affected by gut microbiota. LC mice receiving SP were gavaged with Veillonella parvula. Likewise, hepatic stellate cells (HSC) and hepatocytes (HC) were induced with conditioned medium (CM) of Veillonella parvula. RESULTS: SP alleviated LC in mice by restoring gut barrier function and maintaining gut microbiota balance, with Veillonella as the key genus. The Veillonella parvula gavage on LC mice reversed the ameliorative effect of SP. The CM of Veillonella parvula promoted the activation of HSC and the release of IL-6, IL-1ß, and TNF-α. Also, the CM of Veillonella parvula induced HC pyroptosis and the release of ALT and AST. Veillonella parvula represented an imbalance in the gut microbiota, thus enhancing gut-derived endotoxins in the liver with the main target being Tlr4/Nlrp3. Inhibition of Tlr4 blocked Veillonella parvula-induced HC damage, HSC activation, and subsequent LC progression. CONCLUSION: SP-mediated gut microbiota regulation ameliorates ConA-related LC progression by inhibiting Tlr4/Nlrp3 in the liver.

Isolation, identification, and significance of salivary Veillonella spp., Prevotella spp., and Prevotella salivae in patients with inflammatory bowel disease.

The global prevalence of inflammatory bowel disease (IBD) is on the rise, prompting significant attention from researchers worldwide. IBD entails chronic inflammatory disorders of the intestinal tract, characterized by alternating flares and remissions. Through high-throughput sequencing, numerous studies have unveiled a potential microbial signature for IBD patients showing intestinal enrichment of oral-associated bacteria. Simultaneously, the oral microbiome can be perturbed by intestinal inflammation. Our prior investigation, based on 16S rRNA amplicon sequencing, underscored elevated abundance of Veillonella spp. and Prevotella spp. in the salivary microbiomes of IBD patients. Noteworthy, Prevotella salivae emerged as a distinct species significantly associated with IBD. P. salivae is an under-recognized pathogen that was found to play a role in both oral and systemic diseases. In this study, we delve deeper into the salivary microbiomes of both IBD patients and healthy controls. Employing diverse cultivation techniques and real-time quantitative polymerase chain reactions (RT-qPCR), we gauged the prevalence and abundance of Veillonella spp., Prevotella spp., and P. salivae. Our isolation efforts yielded 407 and 168 strains of Veillonella spp., as well as 173 and 90 strains of Prevotella spp., from the saliva samples of IBD patients and healthy controls, respectively. Veillonella-vancomycin agar emerged as the discerning choice for optimal Veillonella spp. cultivation, while Schaedler kanamycin-vancomycin agar proved to be the most suitable medium for cultivating Prevotella spp. strains. Comparing our RT-qPCR findings to the previous 16S rRNA amplicon sequencing data, the results corroborated the higher abundance of Veillonella spp., Prevotella spp., and P. salivae in the saliva of IBD patients compared to healthy controls. However, it's worth noting that in contrast to RT-qPCR, the 16S rRNA amplicon sequencing data revealed greater absolute abundance of all three bacterial groups in both IBD patients and controls.

Cooperative interactions between Veillonella ratti and Lactobacillus acidophilus ameliorate DSS-induced ulcerative colitis in mice.

Veillonella and Lactobacillus species are key regulators of a healthy gut environment through metabolic cross-feeding, influencing lactic acid and short-chain fatty acid (SCFA) levels, which are crucial for gut health. This study aims to investigate how Veillonella ratti (V. ratti) and Lactobacillus acidophilus (LA) interact with each other and alleviate dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in a mouse model. We assess their metabolic interactions regarding carbon sources through co-culturing in a modified medium. In the in vitro experiments, V. ratti and LA were inoculated in mono-cultures and co-culture, and viable cell counts, OD600, pH, lactic acid, glucose and SCFAs were measured. For the in vivo experiment, 60 C57BL/6 mice were randomly divided into five groups and administered V. ratti and LA alone or in combination via oral gavage (1 × 109 CFU mL-1 per day per mouse) for 14 days. On the seventh day, 2.5% DSS was added to the drinking water to induce colitis. The effects of these probiotics on UC were evaluated by assessing intestinal barrier integrity and intestinal inflammation in the gut microenvironment. In vitro results demonstrated that co-culturing V. ratti with LA significantly increased viable cell numbers, lactic acid production, and SCFA production, while reducing pH and glucose levels in the medium. In vivo findings revealed that intervention with V. ratti, particularly in combination with LA, alleviated symptoms, including weight loss, colon shortening, and tissue damage. These probiotics mitigated intestinal inflammation by down-regulating pro-inflammatory molecules, such as IL-6, IL-1ß, IL-γ, iNOS, and IFN-γ, as well as oxidative stress markers, including MDA and MPO. Concurrently, they upregulated the activity of anti-inflammatory enzymes, namely, SOD and GSH, and promoted the production of SCFAs. The combined intervention of V. ratti and LA significantly increased acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, and total SCFAs in cecal contents. Furthermore, the intervention of V. ratti and LA increased the abundance of beneficial bacteria, such as Akkermansia, while reducing the abundance of harmful bacteria, such as Escherichia-Shigella and Desulfovibrio, thereby mitigating excessive inflammation. These findings highlight the enhanced therapeutic effects resulting from the interactions between V. ratti and LA, demonstrating the potential of this combined probiotic approach.

Precision modulation of dysbiotic adult microbiomes with a human-milk-derived synbiotic reshapes gut microbial composition and metabolites.

Manipulation of the gut microbiome using live biotherapeutic products shows promise for clinical applications but remains challenging to achieve. Here, we induced dysbiosis in 56 healthy volunteers using antibiotics to test a synbiotic comprising the infant gut microbe, Bifidobacterium longum subspecies infantis (B. infantis), and human milk oligosaccharides (HMOs). B. infantis engrafted in 76% of subjects in an HMO-dependent manner, reaching a relative abundance of up to 81%. Changes in microbiome composition and gut metabolites reflect altered recovery of engrafted subjects compared with controls. Engraftment associates with increases in lactate-consuming Veillonella, faster acetate recovery, and changes in indolelactate and p-cresol sulfate, metabolites that impact host inflammatory status. Furthermore, Veillonella co-cultured in vitro and in vivo with B. infantis and HMO converts lactate produced by B. infantis to propionate, an important mediator of host physiology. These results suggest that the synbiotic reproducibly and predictably modulates recovery of a dysbiotic microbiome.

Berberine might block colorectal carcinogenesis by inhibiting the regulation of B-cell function by Veillonella parvula.

BACKGROUND: Colorectal carcinogenesis and progression are related to the gut microbiota and the tumor immune microenvironment. Our previous clinical trial demonstrated that berberine (BBR) hydrochloride might reduce the recurrence and canceration of colorectal adenoma (CRA). The present study aimed to further explore the mechanism of BBR in preventing colorectal cancer (CRC). METHODS: We performed metagenomics sequencing on fecal specimens obtained from the BBR intervention trial, and the differential bacteria before and after medication were validated using quantitative polymerase chain reaction. We further performed ApcMin/+ animal intervention tests, RNA sequencing, flow cytometry, immunohistochemistry, and enzyme-linked immunosorbent assays. RESULTS: The abundance of fecal Veillonella parvula ( V . parvula ) decreased significantly after BBR administration ( P = 0.0016) and increased through the development from CRA to CRC. Patients with CRC with a higher V. parvula abundance had worse tumor staging and a higher lymph node metastasis rate. The intestinal immune pathway of Immunoglobulin A production was activated, and the expression of TNFSF13B (Tumor necrosis factor superfamily 13b, encoding B lymphocyte stimulator [BLyS]), the representative gene of this pathway, and the genes encoding its receptors (interleukin-10 and transforming growth factor beta) were significantly upregulated. Animal experiments revealed that V. parvula promoted colorectal carcinogenesis and increased BLyS levels, while BBR reversed this effect. CONCLUSION: BBR might inhibit V. parvula and further weaken the immunomodulatory effect of B cells induced by V. parvula , thereby blocking the development of colorectal tumors. TRIAL REGISTRAION: ClinicalTrials.gov, No. NCT02226185.

Veillonella atypica causing retropharyngeal abscess: A rare case presentation.

Veillonella species are obligate anaerobes which are part of the human oral, gut and vaginal microbiota. The genus Veillonella consists of 16 characterized species. Very few infections due to Veillonella atypica have been reported till date. Here we present a case of retropharyngeal abscess due to this organism in a 55-year-old lady.

Site Specialization of Human Oral Veillonella Species.

Veillonella species are abundant members of the human oral microbiome with multiple interspecies commensal relationships. Examining the distribution patterns of Veillonella species across the oral cavity is fundamental to understanding their oral ecology. In this study, we used a combination of pangenomic analysis and oral metagenomic information to clarify Veillonella taxonomy and to test the site specialist hypothesis for the Veillonella genus, which contends that most oral bacterial species are adapted to live at specific oral sites. Using isolate genome sequences combined with shotgun metagenomic sequence data, we showed that Veillonella species have clear, differential site specificity: Veillonella parvula showed strong preference for supra- and subgingival plaque, while closely related V. dispar, as well as more distantly related V. atypica, preferred the tongue dorsum, tonsils, throat, and hard palate. In addition, the provisionally named Veillonella sp. Human Microbial Taxon 780 showed strong site specificity for keratinized gingiva. Using comparative genomic analysis, we identified genes associated with thiamine biosynthesis and the reductive pentose phosphate cycle that may enable Veillonella species to occupy their respective habitats. IMPORTANCE Understanding the microbial ecology of the mouth is fundamental for understanding human physiology. In this study, metapangenomics demonstrated that different Veillonella species have clear ecological preferences in the oral cavity of healthy humans, validating the site specialist hypothesis. Furthermore, the gene pool of different Veillonella species was found to be reflective of their ecology, illuminating the potential role of vitamins and carbohydrates in determining Veillonella distribution patterns and interspecies interactions.

Safety evaluation of Veillonella atypica FB0054 with genotoxicity and subchronic toxicological studies.

Veillonella atypica is a nonmotile, nonsporulating anaerobic bacteria commonly found in various human biofilms. V. atypica FB0054 was isolated from the gastrointestinal tract of marathon runners, who have increased amounts of this species after athletic events. Interestingly, the consumption of this strain by rodents has been shown to increase their treadmill endurance, leading to the hypothesis that consumption of this species may improve athletic performance in humans as well. Further evaluation, in humans, of the usefulness of this strain should be preceded by safety studies. Therefore, the genotoxic and subchronic toxicological potential was evaluated as a contribution to this effort. Genotoxicity investigation was performed using the in vivo comet assay and in vivo mammalian micronucleus assay due to the anaerobic characteristic of the strain. A 90-day, repeated-dose oral toxicity study was performed in rats up to 2200 mg/kg bw/d to investigate general toxicity and identify any target organs. Mitsuoka buffer, a solution shown to preserve the viability of anaerobic bacteria, was used as the vehicle. All three studies revealed no toxicological effects from exposure to FB0054 was isolated from the gastrointestinal tract of marathon runners, who have increased amounts of this species after athletic events. Interestingly, the consumption of this strain by rodents has been shown to increase their treadmill endurance, leading to the hypothesis that consumption of this species may improve athletic performance in humans as well. Further evaluation, in humans, of the usefulness of this strain should be preceded by safety studies. Therefore, the genotoxic and subchronic toxicological potential was evaluated as a contribution to this effort. Genotoxicity investigation was performed using the in vivo comet assay and in vivo mammalian micronucleus assay due to the anaerobic characteristic of the strain. A 90-day, repeated-dose oral toxicity study was performed in rats up to 2200 mg/kg bw/d to investigate general toxicity and identify any target organs. Mitsuoka buffer, a solution shown to preserve the viability of anaerobic bacteria, was used as the vehicle. All three studies revealed no toxicological effects from exposure to FB0054 at the highest doses tested.

Characterization of Oral Veillonella Species in Dental Biofilms in Healthy and Stunted Groups of Children Aged 6-7 Years in East Nusa Tenggara.

Impaired development that causes stunting is one of the most common health problems in Indonesia. In particular, the highest number of cases of stunting in Indonesia was reported in the East Nusa Tenggara (NTT) province. Previous studies have shown a tendency for deteriorating oral hygiene in children with a poor nutritional status. In addition, a higher proportion of oral Veillonella has been reported in children with poor oral hygiene. However, the relationship between populations of oral Veillonella and stunting has not been studied before. Therefore, this study aimed to analyze the oral Veillonella profile in the dental biofilms of healthy and stunted children aged 6-7 years. The participants were 60 elementary school students in the Nangapanda District, Ende, NTT, Indonesia. In this study, real-time polymerase chain reaction was used to examine dental biofilm samples from the healthy (n = 31) and stunted (n = 29) groups. The results revealed that seven oral Veillonella species were found in all groups. However, the number of four oral Veillonella species significantly differed between the healthy and stunted groups: V. denticariosi, V. infantium, V. rogosae, and V. tobetsuensis. This is the first study to demonstrate a potential association between oral Veillonella species and stunting in children.

Antibiotic susceptibility and biofilm-forming ability of Veillonella strains.

INTRODUCTION: Veillonella, known as early colonizers in oral biofilms, take part in some infections in human. Biofilm refers to complex, sessile communities of microbes, which function as strong barriers for bacteria to survive. Biofilm matrixes surrounding bacteria enable them to withstand harsh conditions, protect against immune cells, etc., and also make them resistant to antimicrobial treatments. Thus, the knowledge of antibiotic susceptibility and biofilm formation of Veillonella will shed light on their resistance mechanism. MATERIALS AND METHOD: Their morphology was observed by scanning electron microscopy (SEM). According to the performance standards for antibiotic susceptibility testing of the Clinical & Laboratory Standards Institute, the Agar dilution method was used to study the susceptibility of Veillonella strains to eight antibiotics (ampicillin, piperacillin-tazobactam, cefoxitin, tetracycline, moxifloxacin, clindamycin, metronidazole, and vancomycin). In addition, we applied the crystal violet staining method to reveal the processes of biofilm formation of these Veillonella strains. RESULTS: V. rogosae, V. nakazawae, and V. parvula were isolated from oral cavities of healthy adults and V. ratti was isolated from dairy goat droppings. Observations by scanning electron microscopy showed that Veillonella were spherical and arranged in single or short chains. The diameter of a single cell was about 0.3-0.5 µm. The Minimum Inhibitory Concentrations (MICs) of the antibiotics were determined and the results showed that these four strains were all sensitive to cefoxitin, tetracycline, moxifloxacin, clindamycin and metronidazole. Among the four strains, V. ratti was resistant to piperacillin-tazobactam, and V. rogosae and V. nakazawae were resistant to ampicillin. The vancomycin susceptibility of the four Veillonella strains varied greatly. The MICs of vancomycin against V. rogosae and V. ratti were greater than 256 µg/mL but the MICs of vancomycin against V. nakazawae and V. parvula were less than 2 µg/mL. V. parvula had significantly higher biofilm-forming ability than the other three strains (p < 0.05) and V. nakazawae had the weakest biofilm-forming ability. CONCLUSION: In this study, V. rogosae, V. nakazawae, V. parvula and V. ratti were isolated and identified. The four strains of Veillonella showed differences in MIC values for different antibiotics and biofilm-forming ability.

Inflammation-associated nitrate facilitates ectopic colonization of oral bacterium Veillonella parvula in the intestine.

Colonization of the intestine by oral microbes has been linked to multiple diseases such as inflammatory bowel disease and colon cancer, yet mechanisms allowing expansion in this niche remain largely unknown. Veillonella parvula, an asaccharolytic, anaerobic, oral microbe that derives energy from organic acids, increases in abundance in the intestine of patients with inflammatory bowel disease. Here we show that nitrate, a signature metabolite of inflammation, allows V. parvula to transition from fermentation to anaerobic respiration. Nitrate respiration, through the narGHJI operon, boosted Veillonella growth on organic acids and also modulated its metabolic repertoire, allowing it to use amino acids and peptides as carbon sources. This metabolic shift was accompanied by changes in carbon metabolism and ATP production pathways. Nitrate respiration was fundamental for ectopic colonization in a mouse model of colitis, because a V. parvula narG deletion mutant colonized significantly less than a wild-type strain during inflammation. These results suggest that V. parvula harness conditions present during inflammation to colonize in the intestine.

A Co-Association of Streptococcus mutans and Veillonella parvula/dispar in Root Caries Patients and In Vitro Biofilms.

Root caries in geriatric patients is a growing problem as more people are maintaining their natural teeth into advanced age. We determined the levels of various bacterial species previously implicated in root caries disease or health using quantitative real-time PCR in a pilot study of 7 patients with 1 to 4 root caries lesions per person. Levels of 12 different species on diseased roots compared to healthy (contralateral control) roots were measured. Four species were found at significantly higher levels on diseased roots (Streptococcus mutans, Veillonella parvula/dispar, Actinomyces naeslundii/viscosus, and Capnocytophaga granulosa) compared across all plaque samples. The level of colonization by these species varied dramatically (up to 1,000-fold) between patients, indicating different patients have different bacteria contributing to root caries disease. Neither of the two species previously reported to correlate with healthy roots (C. granulosa and Delftia acidovorans) showed statistically significant protective roles in our population, although D. acidovorans showed a trend toward higher levels on healthy teeth (P = 0.08). There was a significant positive correlation between higher levels of S. mutans and V. parvula/dispar on the same diseased teeth. In vitro mixed biofilm studies demonstrated that co-culturing S. mutans and V. parvula leads to a 50 to 150% increase in sucrose-dependent biofilm mass compared to S. mutans alone, depending on the growth conditions, while V. parvula alone did not form in vitro biofilms. The presence of V. parvula also decreased the acidification of S. mutans biofilms when grown in artificial saliva and enhanced the health of mixed biofilms.

An Overview of Adenoid Microbiome Using 16S rRNA Gene Sequencing-Based Metagenomic Analysis.

Background and Objectives: the upper respiratory tract harbors the highest bacterial density in the whole respiratory system. Adenoids, which are located in the nasopharynx, are a major site of bacterial colonies in the upper airways. Our goal was to use culture-independent molecular techniques to identify the breadth of bacterial diversity in the adenoid vegetations of children suffering from chronic rhinosinusitis and obstructive sleep apnea. Materials and methods: in total, 21 adenoid samples were investigated using amplification and sequencing of the V3-V4 hypervariable region of the bacterial 16S rRNA gene. Results: among the most common bacterial species found were Veillonella atypica, Fusobactrium nucelatum, Shaalia odontolytica, and Moraxella catarrhalis. Veillonella atypica and Fusbacteriumnucelatum dominated the microbiome in all 21 samples, attributing to more than 60% of all detected genetic material. Conclusions: since both Veillonella atypica and Fusobacterium nucleatum are, predominantly, oral cavity and dental microorganisms, our findings may suggest oral microbiome migration deeper into the oropharynx and nasopharynx where these bacteria colonize adenoid vegetations.

Polymicrobial bacteremia due to Lactobacillus jensenii and Veillonella montpellierensis in a pregnant patient; case report and review of literature.

Prompt and accurate diagnosis of polymicrobial bacteremia, which causes the difficulty in anti-infective treatments, poor treatment outcome and high mortality, is essential for initiating effective antimicrobial therapy. Here we present a case of bacteremia caused by two types of uncommon bacteria, Lactobacillus jenseniand and Veillonella montpellierensis in a 29-year-old pregnant woman at 33 weeks of gestation with anemia due to iron deficiency. She had no comorbidity or other chronic illnesses and was successfully treated with appropriate antibiotic use.

Severe disseminated Veillonella parvula infection including endocarditis, bilateral psoas abscess, discitis, and osteomyelitis but sparing spinal and hip prostheses: a case report.

BACKGROUND: Veillonella species are an opportunistically pathogenic commensal anaerobic Gram-negative coccus commonly found in the oral, genitourinary, respiratory, and intestinal tract of humans and some animals. Infection is rare, even in immunocompromised hosts, and has been identified to cause a wide array of different infections, including endocarditis, osteomyelitis, and meningitis. CASE PRESENTATION: An 82-year-old Caucasian male retired ex-gymnast presented to the emergency department with a 2-week history of acute on chronic lower back pain without clear precipitant. He displayed no systemic symptoms, and had not sustained any recent injuries. Initial blood and radiological investigation did not reveal an infective or mechanical cause for his pain; however, a few days into admission, he developed a fever and signs of sepsis. A thorough septic screen was performed, including a spinal magnetic resonance imaging scan, which did not reveal any abnormalities. Blood cultures revealed Veillonella parvula bacteremia, with subsequently repeated magnetic resonance imaging displaying rapid disseminated infection including bilateral psoas abscess, discitis, and osteomyelitis. Infective endocarditis was later identified with echocardiogram. He received intravenous ceftriaxone and later oral amoxicillin and clavulanic and recovered on 6-month follow-up. CONCLUSIONS: This case illustrates the potential pathogenicity and unexpected rapid course of Veillonella parvula infection even in an immunocompetent host presenting with back pain. This case highlights the critical importance of a thorough septic screen when investigating patients for early signs of sepsis.