scholarly journals Exploring novel probiotic mechanisms ofStreptococcusA12 with functional genomics

2019 ◽  
Author(s):  
K Lee ◽  
AR Walker ◽  
B Chakraborty ◽  
JR Kaspar ◽  
MM Nascimento ◽  
...  

AbstractHealth-associated biofilms in the oral cavity are composed of a diverse group of microbial species that can foster an environment that is less favorable for the outgrowth of dental caries pathogens, likeStreptococcus mutans.A novel oral bacterium, designatedStreptococcusA12, was previously isolated from supragingival dental plaque of a caries-free individual, and was shown to interfere potently with the growth and virulence properties ofS. mutans. Here, we apply functional genomics to begin to identify molecular mechanisms used by A12 to antagonize, and to resist the antagonistic factors of,S. mutans.Using bioinformatics, genes that could encode factors that enhance the ability of A12 to compete withS. mutanswere identified. Selected genes, designated aspotentialcompetitive factors (pcf), were deleted. Certain mutant derivatives showed a reduced capacity to compete withS. mutanscompared to the parental strain. The A12pcfOmutant lost the ability to inhibitcomX-inducingpeptide (XIP) signaling byS. mutans, while mutants in thepcfFEGlocus were impaired in sensing of, and were more sensitive to, the lantibiotic nisin. Loss of PcfV, annotated as a colicin V biosynthetic protein, resulted in diminished antagonism ofS. mutans.Collectively, the data provide new insights into the complexities and variety of factors that affect biofilm ecology and virulence. Continued exploration of the genomic and physiologic factors that distinguish commensals from truly beneficial members of the oral microbiota will lead to a better understanding of the microbiome and new approaches to promote oral health.ImportanceAdvances in defining the composition of health-associated biofilms have highlighted the important role for beneficial species in maintaining health. Comparatively little, however, has been done to address the genomic and physiological basis underlying the probiotic mechanisms of beneficial commensals. In this study, we explored the ability of a novel oral bacterial isolate,StreptococcusA12, to compete with the dental pathogenStreptococcus mutans, using various gene products with diverse functions. A12 displayed enhanced competitiveness by: i) disrupting intercellular communication pathways ofS. mutans, ii) sensing and resisting antimicrobial peptides, and iii) producing factors involved in the production of a putative antimicrobial compound. Research on the probiotic mechanisms employed byStreptococcusA12 is providing essential insights into how beneficial bacteria may help maintain oral health, which will aid in the development of biomarkers and therapeutics that can improve the practice of clinical dentistry.

2019 ◽  
Vol 85 (21) ◽  
Author(s):  
K. Lee ◽  
A. R. Walker ◽  
B. Chakraborty ◽  
J. R. Kaspar ◽  
M. M. Nascimento ◽  
...  

ABSTRACT Health-associated biofilms in the oral cavity are composed of a diverse group of microbial species that can foster an environment that is less favorable for the outgrowth of dental caries pathogens, like Streptococcus mutans. A novel oral bacterium, designated Streptococcus A12, was previously isolated from supragingival dental plaque of a caries-free individual and was shown to interfere potently with the growth and virulence properties of S. mutans. In this study, we applied functional genomics to begin to identify molecular mechanisms used by A12 to antagonize, and to resist the antagonistic factors of, S. mutans. Using bioinformatics, genes that could encode factors that enhance the ability of A12 to compete with S. mutans were identified. Selected genes, designated potential competitive factors (pcf), were deleted. Certain mutant derivatives showed a reduced capacity to compete with S. mutans compared to that of the parental strain. The A12 pcfO mutant lost the ability to inhibit comX-inducing peptide (XIP) signaling by S. mutans, while mutants with changes in the pcfFEG locus were impaired in sensing of, and were more sensitive to, the lantibiotic nisin. Loss of PcfV, annotated as a colicin V biosynthetic protein, resulted in diminished antagonism of S. mutans. Collectively, the data provide new insights into the complexities and variety of factors that affect biofilm ecology and virulence. Continued exploration of the genomic and physiological factors that distinguish commensals from truly beneficial members of the oral microbiota will lead to a better understanding of the microbiome and new approaches to promote oral health. IMPORTANCE Advances in defining the composition of health-associated biofilms have highlighted the important role of beneficial species in maintaining health. Comparatively little, however, has been done to address the genomic and physiological bases underlying the probiotic mechanisms of beneficial commensals. In this study, we explored the ability of a novel oral bacterial isolate, Streptococcus A12, to compete with the dental pathogen Streptococcus mutans using various gene products with diverse functions. A12 displayed enhanced competitiveness by (i) disrupting intercellular communication pathways of S. mutans, (ii) sensing and resisting antimicrobial peptides, and (iii) producing factors involved in the production of a putative antimicrobial compound. Research on the probiotic mechanisms employed by Streptococcus A12 is providing essential insights into how beneficial bacteria may help maintain oral health, which will aid in the development of biomarkers and therapeutics that can improve the practice of clinical dentistry.


2021 ◽  
Vol 9 (8) ◽  
pp. 1616
Author(s):  
Natalia S. Rozas ◽  
Gena D. Tribble ◽  
Cameron B. Jeter

Patients with Parkinson’s disease (PD) are at increased risk of aspiration pneumonia, their primary cause of death. Their oral microbiota differs from healthy controls, exacerbating this risk. Our goal was to explore if poor oral health, poor oral hygiene, and dysphagia status affect the oral microbiota composition of these patients. In this cross-sectional case-control study, the oral microbiota from hard and soft tissues of patients with PD (n = 30) and age-, gender-, and education-matched healthy controls (n = 30) was compared using 16S rRNA gene sequencing for bacterial identification. Study participants completed dietary, oral hygiene, drooling, and dysphagia questionnaires, and an oral health screening. Significant differences in soft tissue beta-diversity (p < 0.005) were found, and a higher abundance of opportunistic oral pathogens was detected in patients with PD. Factors that significantly influenced soft tissue beta-diversity and microbiota composition include dysphagia, drooling (both p < 0.05), and salivary pH (p < 0.005). Thus, patients with PD show significant differences in their oral microbiota compared to the controls, which may be due, in part, to dysphagia, drooling, and salivary pH. Understanding factors that alter their oral microbiota could lead to the development of diagnostic and treatment strategies that improve the quality of life and survivability of these patients.


Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4071
Author(s):  
Karolina Wiatrak ◽  
Tadeusz Morawiec ◽  
Rafał Rój ◽  
Patryk Kownacki ◽  
Aleksandra Nitecka-Buchta ◽  
...  

The aim of this study was to evaluate the effect of toothpaste containing natural tea tree essential oil (TTO) and ethanolic extract of propolis (EEP), on microflora and selected indicators of oral health in patients using removable acrylic partial dentures. Fifty patients with varying conditions of hygiene were divided into two groups. The study group received the toothpaste with TTO and EEP, while the control group received the same toothpaste but without TTO and EEP. At the first visit, oral hygiene and hygiene of the prostheses were carried out. Control visits took place 7 and 28 days later and compared to baseline. Indexes like API (Approximal Plaque Index), mSBI (modified Sulcus Bleeding Index), OHI-s (simplified Oral Hygiene Index), and DPI (Denture Plaque Index) were assessed in three subsequent stages, and swabs were collected from floor of the mouth area to assess the microbiota. After 7 and 28 days of using the toothpaste with TTO and EEP, a statistically significant decrease of the examined indicator values were observed in the study group as compared to the values upon the initial visit. The number of isolated strains of microorganisms in the study group was decreased or maintained at the same level, whereas in the control group an increase in the number of isolated strains was observed. The observed stabilization of oral microbiota in patients from the study group confirms the beneficial activity of toothpaste containing EEP and TTO compared to the control group.


2021 ◽  
Vol 9 (7) ◽  
pp. 1450
Author(s):  
Yoann Maitre ◽  
Rachid Mahalli ◽  
Pierre Micheneau ◽  
Alexis Delpierre ◽  
Marie Guerin ◽  
...  

This systematic review aims to identify probiotics and prebiotics for modulating oral bacterial species associated with mental disorders. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guideline, we search the electronic MEDLINE database published till January 2021 to identify the studies on probiotics and/or prebiotics for preventing and treating major oral dysbiosis that provokes mental disorders. The outcome of the search produces 374 records. After excluding non-relevant studies, 38 papers were included in the present review. While many studies suggest the potential effects of the oral microbiota on the biochemical signalling events between the oral microbiota and central nervous system, our review highlights the limited development concerning the use of prebiotics and/or probiotics in modulating oral dysbiosis potentially involved in the development of mental disorders. However, the collected studies confirm prebiotics and/or probiotics interest for a global or targeted modulation of the oral microbiome in preventing or treating mental disorders. These outcomes also offer exciting prospects for improving the oral health of people with mental disorders in the future.


2004 ◽  
Vol 16 (2) ◽  
pp. 87 ◽  
Author(s):  
Le Ann Blomberg ◽  
Kurt A. Zuelke

Functional genomics provides a powerful means for delving into the molecular mechanisms involved in pre-implantation development of porcine embryos. High rates of embryonic mortality (30%), following either natural mating or artificial insemination, emphasise the need to improve the efficiency of reproduction in the pig. The poor success rate of live offspring from in vitro-manipulated pig embryos also hampers efforts to generate transgenic animals for biotechnology applications. Previous analysis of differential gene expression has demonstrated stage-specific gene expression for in vivo-derived embryos and altered gene expression for in vitro-derived embryos. However, the methods used to date examine relatively few genes simultaneously and, thus, provide an incomplete glimpse of the physiological role of these genes during embryogenesis. The present review will focus on two aspects of applying functional genomics research strategies for analysing the expression of genes during elongation of pig embryos between gestational day (D) 11 and D12. First, we compare and contrast current methodologies that are being used for gene discovery and expression analysis during pig embryo development. Second, we establish a paradigm for applying serial analysis of gene expression as a functional genomics tool to obtain preliminary information essential for discovering the physiological mechanisms by which distinct embryonic phenotypes are derived.


2011 ◽  
Vol 4 (1) ◽  
Author(s):  
Wim Crielaard ◽  
Egija Zaura ◽  
Annemarie A Schuller ◽  
Susan M Huse ◽  
Roy C Montijn ◽  
...  

2004 ◽  
Vol 72 (7) ◽  
pp. 3752-3758 ◽  
Author(s):  
Yoonsuk Park ◽  
Özlem Yilmaz ◽  
Il-Young Jung ◽  
Richard J. Lamont

ABSTRACT Porphyromonas gingivalis, one of the causative agents of adult periodontitis, can invade and survive within host epithelial cells. The molecular mechanisms by which P. gingivalis induces uptake and adapts to an intracellular environment are not fully understood. In this study, we have investigated the genetic responses of P. gingivalis internalized within human gingival epithelial cells (GECs) in order to identify factors involved in invasion and survival. We compared the differential display of arbitrarily PCR-amplified gene transcripts in P. gingivalis recovered from GECs with the display of transcripts in P. gingivalis control cultures. Over 20 potential differentially expressed transcripts were identified. Among these, pepO, encoding an endopeptidase, and genes encoding an ATP-binding cassette (ABC) transporter and a cation-transporting ATPase were upregulated in GECs. To investigate the functionality of these gene products, mutants were generated by insertional inactivation. Compared to the parental strain, mutants of each gene showed a significant reduction in their invasion capabilities. In addition, GEC cytoskeletal responses to the mutants were distinct from those induced by the parent. In contrast, adhesion of the mutant strains to GECs was not affected by lack of expression of the gene products. These results suggest that PepO, a cation-transporting ATPase, and an ABC transporter are required for the intracellular lifestyle of P. gingivalis.


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 67-67
Author(s):  
Manabu Nakano ◽  
Miyuki Tanaka ◽  
Fumiaki Abe

Abstract Lactoferrin (LF) and lactoperoxidase (LPO) are known as host defense factors in milk and saliva. LF has antibacterial and biofilm-inhibitory effects against periodontopathic bacteria. LPO catalyzes the formation of hypothiocyanite and exhibits bactericidal activity within a short time. Our research group developed LF- and LPO-containing powders, and examined their applications for oral hygiene. In this presentation, we review the clinical efficacies of LF- and LPO-containing tablets on oral malodor and oral microbiota in humans. We performed a randomized clinical trial to assess the effects of the single ingestion of LF- and LPO-containing tablets on malodor. The main components causing oral malodor are volatile sulfur compounds (VSCs). Subjects with oral malodor ingested a test or placebo tablet in two crossover phases. The concentrations of total VSCs at 10 min after ingestion were significantly lower in the test group than in the placebo group. The effects of LF- and LPO-containing tablets on oral microbiota were also investigated. Elderly subjects ingested test or placebo tablets for 8 weeks. The test group exhibited a significant reduction in Porphyromonas gingivalis compared with the placebo group. Microbiota analysis using next-generation sequencing of the bacterial 16S rRNA genes revealed that the LF- and LPO-containing tablets suppressed the relative abundance of periodontal bacteria, but not that of indigenous bacteria such as Streptococcus. Another trial suggested that the regular intake of LF- and LPO-containing tablets can improve gingival inflammation and oral health-related quality of life in healthy adults. Our findings suggest the potential of LF- and LPO-containing tablets as a daily treatment to maintain good oral health and prevent progression to periodontitis. We consider these effects of LF and LPO to also be applicable to pet food for oral health.


Weed Science ◽  
2010 ◽  
Vol 58 (2) ◽  
pp. 109-117 ◽  
Author(s):  
Joshua S. Yuan ◽  
Laura L. G. Abercrombie ◽  
Yongwei Cao ◽  
Matthew D. Halfhill ◽  
Xin Zhou ◽  
...  

The evolution of glyphosate resistance in weedy species places an environmentally benign herbicide in peril. The first report of a dicot plant with evolved glyphosate resistance was horseweed, which occurred in 2001. Since then, several species have evolved glyphosate resistance and genomic information about nontarget resistance mechanisms in any of them ranges from none to little. Here, we report a study combining iGentifier transcriptome analysis, cDNA sequencing, and a heterologous microarray analysis to explore potential molecular and transcriptomic mechanisms of nontarget glyphosate resistance of horseweed. The results indicate that similar molecular mechanisms might exist for nontarget herbicide resistance across multiple resistant plants from different locations, even though resistance among these resistant plants likely evolved independently and available evidence suggests resistance has evolved at least four separate times. In addition, both the microarray and sequence analyses identified non–target-site resistance candidate genes for follow-on functional genomics analysis.


Sign in / Sign up

Export Citation Format

Share Document