Effects of mutating putative two-component systems on biofilm formation by Streptococcus mutans UA159

Streptococcus mutans in dental biofilms is regularly exposed to cycles of acidic pH during the ingestion of fermentable dietary carbohydrates. The ability of S. mutans to tolerate low pH is crucial for its virulence and pathogenesis in dental caries. To better understand its acid tolerance mechanisms, we performed genome-wide transcriptional analysis of S. mutans in response to an acidic pH signal. The preliminary results showed that adaptation of S. mutans to pH 5.5 induced differential expression of nearly 14 % of the genes in the genome, including 169 upregulated genes and 108 downregulated genes, largely categorized into nine functional groups. One of the most interesting findings was that the genes encoding multiple two-component systems (TCSs), including CiaHR, LevSR, LiaSR, ScnKR, Hk/Rr1037/1038 and ComDE, were upregulated during acid adaptation. Real-time qRT-PCR confirmed the same trend in the expression profiles of these genes at pH 5.5. To determine the roles of these transduction systems in acid adaptation, mutants with a deletion of the histidine-kinase-encoding genes were constructed and assayed for the acid tolerance response (ATR). The results revealed that inactivation of each of these systems resulted in a mutant that was impaired in ATR, since pre-exposure of these mutants to pH 5.5 did not induce the same level of protection against lethal pH levels as the parent did. A competitive fitness assay showed that all the mutants were unable to compete with the parent strain for persistence in dual-strain mixed cultures at acidic pH, although, with the exception of the mutant in liaS, little effect was observed at neutral pH. The evidence from this study suggests that the multiple TCSs are required for S. mutans to orchestrate its signal transduction networks for optimal adaptation to acidic pH.

Download Full-text

Multiple Two-Component Systems of Streptococcus mutans Regulate Agmatine Deiminase Gene Expression and Stress Tolerance

Journal of Bacteriology ◽

10.1128/jb.01054-09 ◽

2009 ◽

Vol 191 (23) ◽

pp. 7363-7366 ◽

Cited By ~ 29

Author(s):

Yaling Liu ◽

Robert A. Burne

Keyword(s):

Gene Expression ◽

Stress Tolerance ◽

Streptococcus Mutans ◽

Thermal Stresses ◽

Low Ph ◽

Component Systems ◽

Two Component ◽

Two Component Systems ◽

Agmatine Deiminase

ABSTRACT Induction of the agmatine deiminase system (AgDS) of Streptococcus mutans requires agmatine and is optimal at low pH. We show here that the VicRK, ComDE, and CiaRH two-component systems influence AgDS gene expression in response to acidic and thermal stresses.

Download Full-text

PepO is a target of the two-component systems VicRK and CovR required for systemic virulence of Streptococcus mutans

Virulence ◽

10.1080/21505594.2020.1767377 ◽

2020 ◽

Vol 11 (1) ◽

pp. 521-536

Author(s):

Lívia A. Alves ◽

Tridib Ganguly ◽

Érika N. Harth-Chú ◽

Jessica Kajfasz ◽

José A. Lemos ◽

...

Keyword(s):

Streptococcus Mutans ◽

Component Systems ◽

Two Component ◽

Two Component Systems

Download Full-text

Role of Streptococcus mutans two-component systems in antimicrobial peptide resistance in the oral cavity

Japanese Dental Science Review ◽

10.1016/j.jdsr.2016.12.002 ◽

2017 ◽

Vol 53 (3) ◽

pp. 86-94 ◽

Cited By ~ 6

Author(s):

Miki Kawada-Matsuo ◽

Hitoshi Komatsuzawa

Keyword(s):

Oral Cavity ◽

Antimicrobial Peptide ◽

Streptococcus Mutans ◽

Component Systems ◽

Two Component ◽

Two Component Systems ◽

Antimicrobial Peptide Resistance

Download Full-text

Systemic inactivation and phenotypic characterization of two-component systems in expression of Streptococcus mutans virulence properties

Letters in Applied Microbiology ◽

10.1111/j.1472-765x.2007.02203.x ◽

2007 ◽

Vol 45 (4) ◽

pp. 398-404 ◽

Cited By ~ 43

Author(s):

C.M. Lévesque ◽

R.W. Mair ◽

J.A Perry ◽

P.C.Y. Lau ◽

Y.-H. Li ◽

...

Keyword(s):

Streptococcus Mutans ◽

Phenotypic Characterization ◽

Component Systems ◽

Two Component ◽

Two Component Systems ◽

Virulence Properties

Download Full-text

Multilevel Control of Competence Development and Stress Tolerance in Streptococcus mutans UA159

Infection and Immunity ◽

10.1128/iai.74.3.1631-1642.2006 ◽

2006 ◽

Vol 74 (3) ◽

pp. 1631-1642 ◽

Cited By ~ 154

Author(s):

Sang-Joon Ahn ◽

Zezhang T. Wen ◽

Robert A. Burne

Keyword(s):

Stress Tolerance ◽

Streptococcus Mutans ◽

Biofilm Formation ◽

Response Regulator ◽

Horse Serum ◽

Environmental Signals ◽

Component Systems ◽

Efficient Induction ◽

Two Component Systems ◽

Multiple Levels

ABSTRACT Genetic competence appears to be important in establishment of biofilms and tolerance of environmental insults. We report here that the development of competence is controlled at multiple levels in a complex network that includes two signal-transducing two-component systems (TCS). Using Streptococcus mutans strain UA159, we demonstrate that the histidine kinase CiaH, but not the response regulator CiaR, causes a dramatic decrease in biofilm formation and in transformation efficiency. Inactivation of comE or comD had no effect on stress tolerance, but transformability of the mutants was poor and was not restored by addition of competence-stimulating peptide (CSP). Horse serum (HS) or bovine serum albumin (BSA) had no impact on transformability of any strains. Interestingly, though, the presence of HS or BSA in combination with CSP was required for efficient induction of comD, comX, and comYA, and induction was dependent on ComDE and CiaH, but not CiaR. Inactivation of comC, encoding CSP, had no impact on transformation, and CiaH was shown to be required for optimal comC expression. This study reveals that S. mutans integrates multiple environmental signals through CiaHR and ComDE to coordinate induction of com genes and that CiaH can exert its influence through CiaR and as-yet-unidentified regulators. The results highlight critical differences in the role and regulation of CiaRH and com genes in different S. mutans isolates and between S. mutans and Streptococcus pneumoniae, indicating that substantial divergence in the role and regulation of TCS and competence genes has occurred in streptococci.

Download Full-text

Pseudomonas aeruginosa biofilm formation on endotracheal tubes requires multiple two-component systems

Journal of Medical Microbiology ◽

10.1099/jmm.0.001199 ◽

2020 ◽

Vol 69 (6) ◽

pp. 906-919 ◽

Cited By ~ 2

Author(s):

Divakar Badal ◽

Abhijith Vimal Jayarani ◽

Mohammed Ameen Kollaran ◽

Aloke Kumar ◽

Varsha Singh

Keyword(s):

Pseudomonas Aeruginosa ◽

Biofilm Formation ◽

Type Species ◽

Content Type ◽

Endotracheal Tubes ◽

Link Type ◽

Component Systems ◽

Two Component ◽

Two Component Systems

Introduction. Indwelling medical devices such as endotracheal tubes (ETTs), urinary catheters, vascular access devices, tracheostomies and feeding tubes are often associated with hospital-acquired infections. Bacterial biofilm formed on the ETTs in intubated patients is a significant risk factor associated with ventilator-associated pneumonia. Pseudomonas aeruginosa is one of the four frequently encountered bacteria responsible for causing pneumonia, and the biofilm formation on ETTs. However, understanding of biofilm formation on ETT and interventions to prevent biofilm remains lagging. The ability to sense and adapt to external cues contributes to their success. Thus, the biofilm formation is likely to be influenced by the two-component systems (TCSs) that are composed of a membrane-associated sensor kinase and an intracellular response regulator. Aim. This study aims to establish an in vitro method to analyse the P. aeruginosa biofilm formation on ETTs, and identify the TCSs that contribute to this process. Methodology. In total, 112 P. aeruginosa PA14 TCS mutants were tested for their ability to form biofilm on ETTs, their effect on quorum sensing (QS) and motility. Results. Out of 112 TCS mutants studied, 56 had altered biofilm biomass on ETTs. Although the biofilm formation on ETTs is QS-dependent, none of the 56 loci controlled quorum signal. Of these, 18 novel TCSs specific to ETT biofilm were identified, namely, AauS, AgtS, ColR, CopS, CprR, NasT, KdpD, ParS, PmrB, PprA, PvrS, RcsC, PA14_11120, PA14_32580, PA14_45880, PA14_49420, PA14_52240, PA14_70790. The set of 56 included the GacS network, TCS proteins involved in fimbriae synthesis, TCS proteins involved in antimicrobial peptide resistance, and surface-sensing. Additionally, several of the TCS-encoding genes involved in biofilm formation on ETTs were found to be linked to flagellum-dependent swimming motility. Conclusions. Our study established an in vitro method for studying P. aeruginosa biofilm formation on the ETT surfaces. We also identified novel ETT-specific TCSs that could serve as targets to prevent biofilm formation on indwelling devices frequently used in clinical settings.

Download Full-text

Involvement of the Novel Two-Component NsrRS and LcrRS Systems in Distinct Resistance Pathways against Nisin A and Nukacin ISK-1 in Streptococcus mutans

Applied and Environmental Microbiology ◽

10.1128/aem.00780-13 ◽

2013 ◽

Vol 79 (15) ◽

pp. 4751-4755 ◽

Cited By ~ 19

Author(s):

Miki Kawada-Matsuo ◽

Yuichi Oogai ◽

Takeshi Zendo ◽

Junichi Nagao ◽

Yukie Shibata ◽

...

Keyword(s):

Streptococcus Mutans ◽

Abc Transporter ◽

The Novel ◽

Content Type ◽

Component Systems ◽

Two Component ◽

Two Component Systems

ABSTRACTThe novel two-component systems NsrRS and LcrRS are individually associated with resistance against the distinct lantibiotics nisin A and nukacin ISK-1 inStreptococcus mutans. NsrRS regulates the expression of NsrX, which is associated with nisin A binding, and LcrRS regulates the expression of the ABC transporter LctFEG.

Download Full-text