ciaR impacts biofilm formation by regulating an arginine biosynthesis pathway in Streptococcus sanguinis SK36

Reactive oxygen species (ROS)-mediated oxidative stress and DNA damage have recently been recognized as contributing to the efficacy of most bactericidal antibiotics, irrespective of their primary macromolecular targets. Inhibitors of targets involved in both combating oxidative stress as well as being required for in vivo survival may exhibit powerful synergistic action. This study demonstrates that the de novo arginine biosynthetic pathway in Mycobacterium tuberculosis (Mtb) is up-regulated in the early response to the oxidative stress-elevating agent isoniazid or vitamin C. Arginine deprivation rapidly sterilizes the Mtb de novo arginine biosynthesis pathway mutants ΔargB and ΔargF without the emergence of suppressor mutants in vitro as well as in vivo. Transcriptomic and flow cytometry studies of arginine-deprived Mtb have indicated accumulation of ROS and extensive DNA damage. Metabolomics studies following arginine deprivation have revealed that these cells experienced depletion of antioxidant thiols and accumulation of the upstream metabolite substrate of ArgB or ArgF enzymes. ΔargB and ΔargF were unable to scavenge host arginine and were quickly cleared from both immunocompetent and immunocompromised mice. In summary, our investigation revealed in vivo essentiality of the de novo arginine biosynthesis pathway for Mtb and a promising drug target space for combating tuberculosis.

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Murein Hydrolase LytF of Streptococcus sanguinis and the Ecological Consequences of Competence Development

Applied and Environmental Microbiology ◽

10.1128/aem.01709-17 ◽

2017 ◽

Vol 83 (24) ◽

Cited By ~ 5

Author(s):

Nyssa Cullin ◽

Sylvio Redanz ◽

Kirsten J. Lampi ◽

Justin Merritt ◽

Jens Kreth

Keyword(s):

Dental Caries ◽

Oral Cavity ◽

Cell Morphology ◽

Biofilm Formation ◽

Oral Bacteria ◽

Tooth Surface ◽

Content Type ◽

Streptococcus Sanguinis ◽

Murein Hydrolase ◽

Biofilm Development

ABSTRACT The overall health of the oral cavity is dependent on proper homeostasis between health-associated bacterial colonizers and bacteria known to promote dental caries. Streptococcus sanguinis is a health-associated commensal organism, a known early colonizer of the acquired tooth pellicle, and is naturally competent. We have shown that LytF, a competence-controlled murein hydrolase, is capable of inducing the release of extracellular DNA (eDNA) from oral bacteria. Precipitated LytF and purified LytF were used as treatments against planktonic cultures and biofilms. Larger amounts of eDNA were released from cultures treated with protein samples containing LytF. Additionally, LytF could affect biofilm formation and cellular morphology. Biofilm formation was significantly decreased in the lytF-complemented strain, in which increased amounts of LytF are present. The same strain also exhibited cell morphology defects in both planktonic cultures and biofilms. Furthermore, the LytF cell morphology phenotype was reproducible in wild-type cells using purified LytF protein. In sum, our findings demonstrate that LytF can induce the release of eDNA from oral bacteria, and they suggest that, without proper regulation of LytF, cells display morphological abnormalities that contribute to biofilm malformation. In the context of the oral biofilm, LytF may play important roles as part of the competence and biofilm development programs, as well as increasing the availability of eDNA. IMPORTANCE Streptococcus sanguinis, a commensal organism in the oral cavity and one of the pioneer colonizers of the tooth surface, is associated with the overall health of the oral environment. Our laboratory showed previously that, under aerobic conditions, S. sanguinis can produce H2O2 to inhibit the growth of bacterial species that promote dental caries. This production of H2O2 by S. sanguinis also induces the release of eDNA, which is essential for proper biofilm formation. Under anaerobic conditions, S. sanguinis does not produce H2O2 but DNA is still released. Determining how S. sanguinis releases DNA is thus essential to understand biofilm formation in the oral cavity.

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A Novel Regulator Modulates Glucan Production, Cell Aggregation and Biofilm Formation in Streptococcus sanguinis SK36

Frontiers in Microbiology ◽

10.3389/fmicb.2018.01154 ◽

2018 ◽

Vol 9 ◽

Cited By ~ 4

Author(s):

Bin Zhu ◽

Lei Song ◽

Xiangzhen Kong ◽

Lorna C. Macleod ◽

Ping Xu

Keyword(s):

Biofilm Formation ◽

Cell Aggregation ◽

Streptococcus Sanguinis ◽

Production Cell

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ArgR and AhrC Are Both Required for Regulation of Arginine Metabolism in Lactococcus lactis

Journal of Bacteriology ◽

10.1128/jb.186.4.1147-1157.2004 ◽

2004 ◽

Vol 186 (4) ◽

pp. 1147-1157 ◽

Cited By ~ 55

Author(s):

Rasmus Larsen ◽

Girbe Buist ◽

Oscar P. Kuipers ◽

Jan Kok

Keyword(s):

Lactococcus Lactis ◽

Double Mutant ◽

Protein Complexes ◽

Dna Binding Proteins ◽

Unique Property ◽

Deletion Mutants ◽

Biosynthesis Pathway ◽

Arginine Metabolism ◽

Arginine Biosynthesis ◽

Arginine Catabolism

ABSTRACT The DNA binding proteins ArgR and AhrC are essential for regulation of arginine metabolism in Escherichia coli and Bacillus subtilis, respectively. A unique property of these regulators is that they form hexameric protein complexes, mediating repression of arginine biosynthetic pathways as well as activation of arginine catabolic pathways. The gltS-argE operon of Lactococcus lactis encodes a putative glutamate or arginine transport protein and acetylornithine deacetylase, which catalyzes an important step in the arginine biosynthesis pathway. By random integration knockout screening we found that derepression mutants had ISS1 integrations in, among others, argR and ahrC. Single as well as double regulator deletion mutants were constructed from Lactococcus lactis subsp. cremoris MG1363. The three arginine biosynthetic operons argCJDBF, argGH, and gltS-argE were shown to be repressed by the products of argR and ahrC. Furthermore, the arginine catabolic arcABD1C1C2TD2 operon was activated by the product of ahrC but not by that of argR. Expression from the promoter of the argCJDBF operon reached similar levels in the single mutants and in the double mutant, suggesting that the regulators are interdependent and not able to complement each other. At the same time they also appear to have different functions, as only AhrC is involved in activation of arginine catabolism. This is the first study where two homologous arginine regulators are shown to be involved in arginine regulation in a prokaryote, representing an unusual mechanism of regulation.

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Indole-3-acetic acid synthesized through the indole-3-pyruvate pathway promotes Candida tropicalis biofilm formation

PLoS ONE ◽

10.1371/journal.pone.0244246 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0244246

Author(s):

Masaru Miyagi ◽

Rachel Wilson ◽

Daisuke Saigusa ◽

Keiko Umeda ◽

Reina Saijo ◽

...

Keyword(s):

Escherichia Coli ◽

Acetic Acid ◽

Candida Tropicalis ◽

Biofilm Formation ◽

Single Species ◽

Signaling Molecules ◽

Biosynthesis Pathway ◽

Metabolomic Analysis ◽

Mixed Species ◽

Indole 3 Acetic Acid

We previously found that the elevated abundance of the fungus Candida tropicalis is positively correlated with the bacteria Escherichia coli and Serratia marcescens in Crohn’s disease patients and the three pathogens, when co-cultured, form a robust mixed-species biofilm. The finding suggests that these three pathogens communicate and promote biofilm formation, possibly through secretion of small signaling molecules. To identify candidate signaling molecules, we carried out a metabolomic analysis of the single-species and triple-species cultures of the three pathogens. This analysis identified 15 metabolites that were highly increased in the triple-species culture. One highly induced metabolite was indole-3-acetic acid (IAA), which has been shown to induce filamentation of certain fungi. We thus tested the effect of IAA on biofilm formation of C. tropicalis and demonstrated that IAA promotes biofilm formation of C. tropicalis. Then, we carried out isotope tracing experiments using 13C-labeled-tryptophan as a precursor to uncover the biosynthesis pathway of IAA in C. tropicalis. The results indicated that C. tropicalis synthesizes IAA through the indole-3-pyruvate pathway. Further studies using inhibitors of the indole-3-pyruvate pathway are warranted to decipher the mechanisms by which IAA influences biofilm formation.

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Cellular L-arginine pools modulate c-di-GMP turnover and biofilm formation in Pseudomonas putida

10.5194/biofilms9-130 ◽

2020 ◽

Author(s):

Laura Barrientos-Moreno ◽

María Antonia Molina-Henares ◽

María Isabel Ramos-González ◽

Manuel Espinosa-Urgel

Keyword(s):

Pseudomonas Putida ◽

Biofilm Formation ◽

Response Regulator ◽

Second Messenger ◽

Colony Morphology ◽

Diguanylate Cyclase ◽

Arginine Biosynthesis ◽

Amino Acid Transport System ◽

Metabolic Signal ◽

Biofilm Development

The intracellular second messenger cyclic diguanylate (c-di-GMP) is broadly conserved in bacteria, where it influences processes such as virulence, stress resistance and biofilm development. In the plant-beneficial bacterium Pseudomonas putida KT2440, the response regulator with diguanylate cyclase activity CfcR is the main contributor to c-di-GMP levels in the stationary phase of growth. When overexpressed, CfcR increases c-di-GMP levels and gives rise to a pleiotropic phenotype that includes enhanced biofilm formation and crinkly colony morphology. Our group has previously reported that insertion mutants in argG and argH, the genes that encode the last two enzymes in the arginine biosynthesis pathway, do not display the crinkly colony morphology phenotype and show decreased c-di-GMP levels even in the presence of cfcR in multicopy (Ramos-Gonz&#225;lez, M.I. et al. 2016. Front. Microbiol. 7, 1093). Here we present results indicating that L-arginine acts both as an environmental and as a metabolic signal that influences the lifestyles of P. putida through the modulation of c-di-GMP levels and changes in the expression of structural elements of biofilms. Exogenous L-arginine partially restores c-di-GMP levels in arginine biosynthesis mutants, a response that is transduced through CfcR and possibly (an)other diguanylate cyclase(s). At least three periplasmic binding proteins, each forming part of an amino acid transport system, contribute in different ways to the response to external L-arginine. We propose that the turnover of the second messenger c-di-GMP is modulated by the state of global arginine pools in the cell resulting both from anabolism and from uptake.

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The potency of cajuputs candy in maintaining the competitive capacity of Streptococcus sanguinis upon Streptococcus mutans

Journal of Functional Food and Nutraceutical ◽

10.33555/jffn.v1i2.29 ◽

2020 ◽

Vol 1 (2) ◽

pp. 87-99 ◽

Cited By ~ 1

Author(s):

Christofora Hanny Wijaya ◽

Bernadeta RE Sari ◽

Boy M Bachtiar

Keyword(s):

Mrna Expression ◽

Volatile Compounds ◽

Streptococcus Mutans ◽

Biofilm Formation ◽

Dna Amount ◽

Biofilm Inhibition ◽

Oral Flora ◽

Streptococcus Sanguinis ◽

Total Dna

Streptococcus mutans were competing Streptococcus sanguinis in biofilm formation. As pioneer colonizer, S. sanguinis were able to control S. mutans growth. This study was aimed to explore the ability of sucrose and non-sucrose cajuputs candies (SCC and NSCC) in maintaining the antagonistic relationship between the indigenous oral flora when they grew as dual-species biofilms (S. sanguinis and S. mutans). The flavored candies (SCC and NSCC) contained cajuput and peppermint oils as the flavor which the volatile compounds had been identified. The unflavored candies were made similar to the flavored candy but excluding the flavor. The flavored candies, unflavored candies, and the control were exposed in vitro to the biofilms. The biofilms were examined for biofilm inhibition capacity, DNA amount, and the expression level of spxB mRNA. The biofilm inhibition by flavored candies were higher than the unflavored ones and were significantly different compared to the control. The flavored candies managed to decrease the total DNA amount in the biofilm, but unflavored samples did not. The qPCR assays showed that the exposure of candies did not alter the proportion of S. sanguinis DNA to S. mutans DNA in the biofilms. Meanwhile, spxB mRNA expression indicated the ability of S.sanguinis to control S. mutans growth.

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Effects of Norspermidine on Dual‐Species Biofilms Composed of Streptococcus mutans and Streptococcus sanguinis

BioMed Research International ◽

10.1155/2019/1950790 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9

Author(s):

Yan Sun ◽

Yihuai Pan ◽

Yu Sun ◽

Mingyun Li ◽

Shengbin Huang ◽

...

Keyword(s):

Streptococcus Mutans ◽

Metabolic Activity ◽

Biofilm Formation ◽

Acid Production ◽

Single Species ◽

Extracellular Polysaccharides ◽

Streptococcus Sanguinis ◽

Crystal Violet Assay ◽

Sem Imaging

The present study aimed at investigating the influence of norspermidine on the formation of dual-species biofilms composed of Streptococcus mutans (S. mutans) and Streptococcus sanguinis (S. sanguinis). Crystal violet assay was conducted to assess the formation of single-species biofilms of S. mutans and S. sanguinis, and the growth curve was carefully observed to monitor the growth of these two species of bacteria. Fluorescence in situ hybridization (FISH) and MTT array were used to analyze the composition and metabolic activity of the dual-species biofilms, respectively. Extracellular polysaccharides (EPS)/bacteria staining, anthrone method, and scanning electron microscopy (SEM) imaging were conducted to study the synthesis of EPS by dual-species biofilms. Lactic acid assay and pH were measured to detect dual-species biofilm acid production. We found that norspermidine had different effects on S. mutans and S. sanguinis including their growth and biofilm formation. Norspermidine regulated the composition of the dual-species biofilms, decreased the ratio of S. mutans in dual-species biofilms, and reduced the metabolic activity, EPS synthesis, and acid production of dual-species biofilms. Norspermidine regulated dual-species biofilms in an ecological way, suggesting that it may be a potent reagent for controlling dental biofilms and managing dental caries.

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Composite genome sequence of Bacillus clausii, a probiotic commercially available as Enterogermina®, and insights into its probiotic properties

10.21203/rs.2.15490/v1 ◽

2019 ◽

Author(s):

Indu Khatri ◽

Gaurav Sharma ◽

Srikrishna Subramanian

Keyword(s):

Biofilm Formation ◽

Bacterial Infections ◽

Kegg Pathway ◽

Probiotic Bacteria ◽

Probiotic Properties ◽

Biosynthesis Pathway ◽

Bacillus Clausii ◽

Kegg Pathway Analysis ◽

Gastrointestinal Conditions ◽

Folate Biosynthesis

Abstract Background: Some of the spore-forming strains of Bacillus probiotics are marketed commercially as they survive harsh gastrointestinal conditions and bestow health benefits to the host. Results: We report the composite genome of Bacillus clausii ENTPro from a commercially available probiotic Enterogermina ® and compare it with the genomes of other Bacillus probiotics. We find that the members of B. clausii species harbor higher heterogeneity at the species as well as genus level. The genes conferring resistance to chloramphenicol, streptomycin, rifampicin, and tetracycline in the B. clausii ENTPro strain could be identified. The genes coding for the bacteriocin gallidermin, which prevents biofilm formation in the pathogens S. aureus and S. epidermidis , were also identified. KEGG Pathway analysis suggested that the folate biosynthesis pathway, which depicts one of the important roles of probiotics in the host, is conserved completely in B. subtilis and minimally in Bacillus clausii and other probiotics. Conclusions: We identified various antibiotic resistance, bacteriocins, stress-related, and adhesion-related domains and industrially relevant pathways, in the genomes of these probiotic bacteria that are likely to help them survive in the harsh gastrointestinal tract, facilitating adhesion to host epithelial cells, persistence during antibiotic treatment and combating bacterial infections.

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