scholarly journals Role of HtrA in Growth and Competence of Streptococcus mutans UA159

2005 ◽  
Vol 187 (9) ◽  
pp. 3028-3038 ◽  
Author(s):  
Sang-Joon Ahn ◽  
José A. C. Lemos ◽  
Robert A. Burne
Keyword(s):  
Genetic Transformation ◽  
Streptococcus Mutans ◽  
Biofilm Formation ◽  
Single Copy ◽  
Growth Stress ◽  
Competence Development ◽  
Cellular Growth ◽  
Functional Connection ◽  
Abnormal Growth ◽  
Multiple Copies

ABSTRACT We report here that HtrA plays a role in controlling growth and competence development for genetic transformation in Streptococcus mutans. Disruption of the gene for HtrA resulted in slow growth at 37°C, reduced thermal tolerance at 42°C, and altered sucrose-dependent biofilm formation on polystyrene surfaces. The htrA mutant also displayed a significantly reduced ability to undergo genetic transformation. A direct association between HtrA and genetic competence was demonstrated by the increased expression of the htrA gene upon exposure to competence-stimulating peptide. The induction of htrA gradually reached a maximum at around 20 min, suggesting that HtrA may be involved in a late competence response. Complementation of the htrA mutation in a single copy on the chromosome of the mutant could rescue the defective growth phenotypes but not transformability, apparently because a second gene, spo0J, immediately downstream of htrA, also affects transformation. The htrA and spo0J genes were shown to be both individually transcribed and cotranscribed and probably have a functional connection in competence development. HtrA regulation appears to be finely tuned in S. mutans, since strains containing multiple copies of htrA exhibited abnormal growth phenotypes. Collectively, the results reveal HtrA to be an integral component of the regulatory network connecting cellular growth, stress tolerance, biofilm formation, and competence development and reveal a novel role for the spo0J gene in genetic transformation.

scholarly journals Streptococcus mutans Lacking sufCDSUB Is Viable, but Displays Major Defects in Growth, Stress Tolerance Responses and Biofilm Formation

2021 ◽  
Vol 12 ◽  
Author(s):  
Kassapa Ellepola ◽  
Xiaochang Huang ◽  
Ryan P. Riley ◽  
Jacob P. Bitoun ◽  
Zezhang Tom Wen
Keyword(s):  
Stress Tolerance ◽  
Streptococcus Mutans ◽  
Biofilm Formation ◽  
Nitrosative Stress ◽  
Growth Stress ◽  
Low Ph ◽  
Luciferase Reporter ◽  
Deficient Mutant ◽  
Oxidative And Nitrosative Stress ◽  
Isoleucine Leucine

Streptococcus mutans appears to possess a sole iron-sulfur (Fe-S) cluster biosynthesis system encoded by the sufCDSUB cluster. This study was designed to examine the role of sufCDSUB in S. mutans physiology. Allelic exchange mutants deficient of the whole sufCDSUB cluster and in individual genes were constructed. Compared to the wild-type, UA159, the sufCDSUB-deficient mutant, Δsuf::kanr, had a significantly reduced growth rate, especially in medium with the absence of isoleucine, leucine or glutamate/glutamine, amino acids that require Fe-S clusters for biosynthesis and when grown with medium adjusted to pH 6.0 and under oxidative and nitrosative stress conditions. Relative to UA159, Δsuf::kanr had major defects in stress tolerance responses with reduced survival rate of > 2-logs following incubation at low pH environment or after hydrogen peroxide challenge. When compared to UA159, Δsuf::kanr tended to form aggregates in broth medium and accumulated significantly less biofilm. As shown by luciferase reporter fusion assays, the expression of sufCDSUB was elevated by > 5.4-fold when the reporter strain was transferred from iron sufficient medium to iron-limiting medium. Oxidative stress induced by methyl viologen increased sufCDSUB expression by > 2-fold, and incubation in a low pH environment led to reduction of sufCDSUB expression by > 7-fold. These results suggest that lacking of SufCDSUB in S. mutans causes major defects in various cellular processes of the deficient mutant, including growth, stress tolerance responses and biofilm formation. In addition, the viability of the deficient mutant also suggests that SUF, the sole Fe-S cluster machinery identified is non-essential in S. mutans, which is not known in any other bacterium lacking the NIF and/or ISC system. However, how the bacterium compensates the Fe-S deficiency and if any novel Fe-S assembly systems exist in this bacterium await further investigation.

scholarly journals Inactivation of the ciaH Gene in Streptococcus mutans Diminishes Mutacin Production and Competence Development, Alters Sucrose-Dependent Biofilm Formation, and Reduces Stress Tolerance

2004 ◽  
Vol 72 (8) ◽  
pp. 4895-4899 ◽  
Author(s):  
Fengxia Qi ◽  
Justin Merritt ◽  
Renate Lux ◽  
Wenyuan Shi
Keyword(s):  
Stress Tolerance ◽  
Streptococcus Mutans ◽  
Histidine Kinase ◽  
Dental Plaque ◽  
Biofilm Formation ◽  
Competence Development ◽  
Clinical Isolates ◽  
Peptide Antibiotics ◽  
Kinase Gene

ABSTRACT Many clinical isolates of Streptococcus mutans produce peptide antibiotics called mutacins. Mutacin production may play an important role in the ecology of S. mutans in dental plaque. In this study, inactivation of a histidine kinase gene, ciaH, abolished mutacin production. Surprisingly, the same mutation also diminished competence development, stress tolerance, and sucrose-dependent biofilm formation.

scholarly journals A Pleiotropic Regulator, Frp, Affects Exopolysaccharide Synthesis, Biofilm Formation, and Competence Development in Streptococcus mutans

2006 ◽  
Vol 74 (8) ◽  
pp. 4581-4589 ◽  
Author(s):  
Bing Wang ◽  
Howard K. Kuramitsu
Keyword(s):  
Streptococcus Mutans ◽  
Biofilm Formation ◽  
Wild Type Strain ◽  
Transformation Efficiency ◽  
Competence Development ◽  
Wild Type ◽  
Cellular Functions ◽  
In The Wild ◽  
Pleiotropic Regulator

ABSTRACT Exopolysaccharide synthesis, biofilm formation, and competence are important physiologic functions and virulence factors for Streptococcus mutans. In this study, we report the role of Frp, a transcriptional regulator, on the regulation of these traits crucial to pathogenesis. An Frp-deficient mutant showed decreased transcription of several genes important in virulence, including those encoding fructosyltransferase (Ftf), glucosyltransferase B (GtfB), and GtfC, by reverse transcription and quantitative real-time PCR. Expression of Ftf was decreased in the frp mutant, as assessed by Western blotting as well as by the activity assays. Frp deficiency also inhibited the production of GtfB in the presence of glucose and sucrose as well as the production of GtfC in the presence of glucose. As a consequence of the effects on GtfB and -C, sucrose-induced biofilm formation was decreased in the frp mutant. The expression of competence mediated by the competence-signaling peptide (CSP) system, as assessed by comC gene transcription, was attenuated in the frp mutant. As a result, the transformation efficiency was decreased in the frp mutant but was partially restored by adding synthetic CSP. Transcription of the frp gene was significantly increased in the frp mutant under all conditions tested, indicating that frp transcription is autoregulated. Furthermore, complementation of the frp gene in the frp mutant restored transcription of the affected genes to levels similar to those in the wild-type strain. These results suggest that Frp is a novel pleiotropic effector of multiple cellular functions and is involved in the modulation of exopolysaccharide synthesis, sucrose-dependent biofilm formation, and competence development.

scholarly journals Trk2 Potassium Transport System in Streptococcus mutans and Its Role in Potassium Homeostasis, Biofilm Formation, and Stress Tolerance

2016 ◽  
Vol 198 (7) ◽  
pp. 1087-1100 ◽  
Author(s):  
Gursonika Binepal ◽  
Kamal Gill ◽  
Paula Crowley ◽  
Martha Cordova ◽  
L. Jeannine Brady ◽  
...  
Keyword(s):  
Stress Tolerance ◽  
Streptococcus Mutans ◽  
Transport System ◽  
Biofilm Formation ◽  
Cellular Response ◽  
Pathogenic Bacteria ◽  
Transport Systems ◽  
Content Type ◽  
Growth And Survival ◽  
Dental Biofilm

ABSTRACTPotassium (K+) is the most abundant cation in the fluids of dental biofilm. The biochemical and biophysical functions of K+and a variety of K+transport systems have been studied for most pathogenic bacteria but not for oral pathogens. In this study, we establish the modes of K+acquisition inStreptococcus mutansand the importance of K+homeostasis for its virulence attributes. TheS. mutansgenome harbors four putative K+transport systems that included two Trk-like transporters (designated Trk1 and Trk2), one glutamate/K+cotransporter (GlnQHMP), and a channel-like K+transport system (Kch). Mutants lacking Trk2 had significantly impaired growth, acidogenicity, aciduricity, and biofilm formation. [K+] less than 5 mM eliminated biofilm formation inS. mutans. The functionality of the Trk2 system was confirmed by complementing anEscherichia coliTK2420 mutant strain, which resulted in significant K+accumulation, improved growth, and survival under stress. Taken together, these results suggest that Trk2 is the main facet of the K+-dependent cellular response ofS. mutansto environment stresses.IMPORTANCEBiofilm formation and stress tolerance are important virulence properties of caries-causingStreptococcus mutans. To limit these properties of this bacterium, it is imperative to understand its survival mechanisms. Potassium is the most abundant cation in dental plaque, the natural environment ofS. mutans. K+is known to function in stress tolerance, and bacteria have specialized mechanisms for its uptake. However, there are no reports to identify or characterize specific K+transporters inS. mutans. We identified the most important system for K+homeostasis and its role in the biofilm formation, stress tolerance, and growth. We also show the requirement of environmental K+for the activity of biofilm-forming enzymes, which explains why such high levels of K+would favor biofilm formation.

scholarly journals A Novel Gene Involved in the Survival of Streptococcus mutans under Stress Conditions

2013 ◽  
Vol 80 (1) ◽  
pp. 97-103 ◽  
Author(s):  
Dan Li ◽  
Yukie Shibata ◽  
Toru Takeshita ◽  
Yoshihisa Yamashita
Keyword(s):  
Streptococcus Mutans ◽  
Streptococcus Pyogenes ◽  
Biofilm Formation ◽  
Acid Tolerance ◽  
Stress Conditions ◽  
Insertion Mutagenesis ◽  
Trna Modification ◽  
Content Type ◽  
Virulence Proteins ◽  
Random Insertion

ABSTRACTAStreptococcus mutansmutant defective in aciduricity was constructed by random-insertion mutagenesis. Sequence analysis of the mutant revealed a mutation ingidA, which is known to be involved in tRNA modification inStreptococcus pyogenes. Complementation ofgidAbyS. pyogenesgidArecovered the acid tolerance ofS. mutans. Although thegidA-inactivatedS. pyogenesmutant exhibited significantly reduced expression of multiple extracellular virulence proteins, theS. mutansmutant did not. On the other hand, thegidAmutant ofS. mutansshowed reduced ability to withstand exposure to other stress conditions (high osmotic pressure, high temperature, and bacitracin stress) besides an acidic environment. In addition, loss of GidA decreased the capacity for glucose-dependent biofilm formation by over 50%. This study revealed thatgidAplays critical roles in the survival ofS. mutansunder stress conditions, including lower pH.

scholarly journals Effect of a Berry Polyphenolic Fraction on Biofilm Formation, Adherence Properties and Gene Expression of Streptococcus mutans and Its Biocompatibility with Oral Epithelial Cells

Antibiotics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 46
Author(s):  
Mariem Souissi ◽  
Amel Ben Lagha ◽  
Kamel Chaieb ◽  
Daniel Grenier
Keyword(s):  
Epithelial Cells ◽  
Streptococcus Mutans ◽  
Biofilm Formation ◽  
Cell Model ◽  
Pcr Analysis ◽  
Adhesion Properties ◽  
Oral Epithelial Cells ◽  
Polymerase Chain ◽  
Oral Epithelial ◽  
Wild Blueberry

The ability of Streptococcus mutans to adhere to oral surfaces and form biofilm is a key step in the tooth decay process. The aim of this study was to investigate a berry (wild blueberry, cranberry, and strawberry) polyphenolic fraction, commercialized as Orophenol®, for its antibacterial, anti-biofilm, and anti-adhesion properties on S. mutans. Moreover, the biocompatibility of the fraction with human oral epithelial cells was assessed. Phenolic acids, flavonoids (flavonols, anthocyanins, flavan-3-ols), and procyanidins made up 10.71%, 19.76%, and 5.29% of the berry polyphenolic fraction, respectively, as determined by chromatography and mass spectrometry. The berry polyphenolic preparation dose-dependently inhibited S. mutans biofilm formation while not reducing bacterial growth. At concentrations ranging from 250 to 1000 µg/mL, the fraction inhibited the adhesion of S. mutans to both saliva-coated hydroxyapatite and saliva-coated nickel–chrome alloy. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis showed that incubating S. mutans with the berry polyphenolic fraction was associated with a reduced expression of luxS gene, which regulates quorum sensing in S. mutans. The berry fraction did not show any significant cytotoxicity in an oral epithelial cell model. In conclusion, Orophenol®, which is a mixture of polyphenols from wild blueberry, cranberry and strawberry, possesses interesting anti-caries properties while being compatible with oral epithelial cells.

Human actin genes are single copy for alpha-skeletal and alpha-cardiac actin but multicopy for beta- and gamma-cytoskeletal genes: 3' untranslated regions are isotype specific but are conserved in evolution

1983 ◽  
Vol 3 (10) ◽  
pp. 1783-1791
Author(s):  
P Ponte ◽  
P Gunning ◽  
H Blau ◽  
L Kedes
Keyword(s):  
Human Genome ◽  
Single Copy ◽  
Untranslated Regions ◽  
Muscle Actin ◽  
Actin Genes ◽  
Hybridization Probes ◽  
Single Exception ◽  
Multiple Copies ◽  
Human Genomic ◽  
Unambiguous Assignment

We have constructed isotype-specific subclones from the 3' untranslated regions of alpha-skeletal, alpha-cardiac, beta-cytoskeletal, and gamma-cytoskeletal actin cDNAs. These clones have been used as hybridization probes to assay the number and organization of these actin isotypes in the human genome. Hybridization of these probes to human genomic actin clones (Engel et al., Proc. Natl. Acad. Sci. U.S.A. 78:4674-4678, 1981; Engel et al., Mol. Cell. Biol. 2:674-684, 1982) has allowed the unambiguous assignment of the genomic clones to isotypically defined actin subfamilies. In addition, only one isotype-specific probe hybridizes to each actin-containing gene, with a single exception. This result suggests that the multiple actin genes in the human genome are not closely linked. Genomic DNA blots probed with these subclones under stringent conditions demonstrate that the alpha-skeletal and alpha-cardiac muscle actin genes are single copy, whereas the cytoskeletal actins, beta and gamma, are present in multiple copies in the human genome. Most of the actin genes of other mammals are cytoplasmic as well. These observations have important implications for the evolution of multigene families.

Genetic Transformation of Streptococcus sanguis (Challis) with Cryptic Plasmids from Streptococcus ferus

1980 ◽  
Vol 28 (3) ◽  
pp. 692-699 ◽  
Author(s):  
Francis L. Macrina ◽  
Patricia H. Wood ◽  
Kevin R. Jones
Keyword(s):  
Genetic Transformation ◽  
Streptococcus Mutans ◽  
Restriction Enzyme ◽  
Deoxyribonucleic Acid ◽  
Cryptic Plasmid ◽  
Common Ancestry ◽  
Erythromycin Resistance ◽  
Streptococcus Sanguis ◽  
Cryptic Plasmids ◽  
Isogenic Strains

By using the basic methodology initially published by Kretschmer et al. (J. Bacteriol. 124 :225-231, 1975), we have been able to introduce phenotypically cryptic plasmids from Streptococcus ferus (formerly Streptococcus mutans subsp. ferus ) into Streptococcus sanguis by genetic transformation. In this system, the entry of the cryptic plasmids is selected indirectly. This is effected with transforming deoxyribonucleic acid mixtures in which the cryptic plasmid deoxyribonucleic acid is present in an approximate 10-fold molar excess with respect to a plasmid (pVA1) known to confer erythromycin resistance. Under such conditions, 5 to 10% of the pVA1-containing erythromycin-resistant transformants were cotransformed with cryptic plasmid deoxyribonucleic acid. pVA1 may be selectively eliminated by growth of its S. sanguis host strain at 42°C, enabling the construction of isogenic strains with and without S. ferus cryptic plasmids. Comparative physiological studies of such strains have failed to reveal any plasmid-conferred phenotypes in S. sanguis. With this procedure, we have been able to physically separate two small cryptic plasmids (2.4 × 10 6 and 2.8 × 10 6 daltons) of S. ferus. Although these plasmids were found naturally to exist in a single S. ferus host, they were able to replicate independently of one another in S. sanguis. Restriction enzyme fingerprinting indicated that these plasmids did not share a common ancestry.

scholarly journals Mediterranean herb extracts inhibit microbial growth of representative oral microorganisms and biofilm formation of Streptococcus mutans

PLoS ONE ◽  
2018 ◽  
Vol 13 (12) ◽  
pp. e0207574 ◽  
Author(s):  
Joachim Hickl ◽  
Aikaterini Argyropoulou ◽  
Maria Eleni Sakavitsi ◽  
Maria Halabalaki ◽  
Ali Al-Ahmad ◽  
...  
Keyword(s):  
Streptococcus Mutans ◽  
Biofilm Formation ◽  
Microbial Growth ◽  
Herb Extracts ◽  
Oral Microorganisms
Sign in / Sign up

Export Citation Format

Share Document