Two-component system AfrQ1Q2 involved in oxytetracycline biosynthesis of Streptomyces rimosus M4018 in a medium-dependent manner

ABSTRACT During infection, bacteria use two-component signal transduction systems to sense and adapt to the dynamic host environment. Despite critically contributing to infection, the activating signals of most of these regulators remain unknown. This also applies to the Staphylococcus aureus ArlRS two-component system, which contributes to virulence by coordinating the production of toxins, adhesins, and a metabolic response that enables the bacterium to overcome host-imposed manganese starvation. Restricting the availability of essential transition metals, a strategy known as nutritional immunity, constitutes a critical defense against infection. In this work, expression analysis revealed that manganese starvation imposed by the immune effector calprotectin or by the absence of glycolytic substrates activates ArlRS. Manganese starvation imposed by calprotectin also activated the ArlRS system even when glycolytic substrates were present. A combination of metabolomics, mutational analysis, and metabolic feeding experiments revealed that ArlRS is activated by alterations in metabolic flux occurring in the latter half of the glycolytic pathway. Moreover, calprotectin was found to induce expression of staphylococcal leukocidins in an ArlRS-dependent manner. These studies indicated that ArlRS is a metabolic sensor that allows S. aureus to integrate multiple environmental stresses that alter glycolytic flux to coordinate an antihost response and to adapt to manganese starvation. They also established that the latter half of glycolysis represents a checkpoint to monitor metabolic state in S. aureus. Altogether, these findings contribute to understanding how invading pathogens, such as S. aureus, adapt to the host during infection and suggest the existence of similar mechanisms in other bacterial species. IMPORTANCE Two-component regulatory systems enable bacteria to adapt to changes in their environment during infection by altering gene expression and coordinating antihost responses. Despite the critical role of two-component systems in bacterial survival and pathogenesis, the activating signals for most of these regulators remain unidentified. This is exemplified by ArlRS, a Staphylococcus aureus global regulator that contributes to virulence and to resisting host-mediated restriction of essential nutrients, such as manganese. In this report, we demonstrate that manganese starvation and the absence of glycolytic substrates activate ArlRS. Further investigations revealed that ArlRS is activated when the latter half of glycolysis is disrupted, suggesting that S. aureus monitors flux through the second half of this pathway. Host-imposed manganese starvation also induced the expression of pore-forming toxins in an ArlRS-dependent manner. Cumulatively, this work reveals that ArlRS acts as a sensor that links nutritional status, cellular metabolism, and virulence regulation.

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Extracellular Ca2+ transients affect poly-(R)-3-hydroxybutyrate regulation by the AtoS-AtoC system in Escherichia coli

Biochemical Journal ◽

10.1042/bj20081169 ◽

2009 ◽

Vol 417 (3) ◽

pp. 667-672 ◽

Cited By ~ 17

Author(s):

Marina C. Theodorou ◽

Ekaterini Tiligada ◽

Dimitrios A. Kyriakidis

Keyword(s):

Escherichia Coli ◽

Channel Blocker ◽

Inhibitory Effect ◽

Dependent Manner ◽

Signal Transduction System ◽

Two Component System ◽

Component System ◽

E Coli ◽

Two Component ◽

Membrane Bound

Escherichia coli is exposed to wide extracellular concentrations of Ca2+, whereas the cytosolic levels of the ion are subject to stringent control and are implicated in many physiological functions. The present study shows that extracellular Ca2+ controls cPHB [complexed poly-(R)-3-hydroxybutyrate] biosynthesis through the AtoS-AtoC two-component system. Maximal cPHB accumulation was observed at higher [Ca2+]e (extracellular Ca2+ concentration) in AtoS-AtoC-expressing E. coli compared with their ΔatoSC counterparts, in both cytosolic and membrane fractions. The reversal of EGTA-mediated down-regulation of cPHB biosynthesis by the addition of Ca2+ and Mg2+ was under the control of the AtoS-AtoC system. Moreover, the Ca2+-channel blocker verapamil reduced total and membrane-bound cPHB levels, the inhibitory effect being circumvented by Ca2+ addition only in atoSC+ bacteria. Histamine and compound 48/80 affected cPHB accumulation in a [Ca2+]e-dependent manner directed by the AtoS-AtoC system. In conclusion, these data provide evidence for the involvement of external Ca2+ on cPHB synthesis regulated by the AtoS-AtoC two-component system, thus linking Ca2+ with a signal transduction system, most probably through a transporter.

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Repression of Escherichia coli PhoP-PhoQ Signaling by Acetate Reveals a Regulatory Role for Acetyl Coenzyme A

Journal of Bacteriology ◽

10.1128/jb.185.8.2563-2570.2003 ◽

2003 ◽

Vol 185 (8) ◽

pp. 2563-2570 ◽

Cited By ~ 21

Author(s):

Joseph A. Lesley ◽

Carey D. Waldburger

Keyword(s):

Escherichia Coli ◽

Coenzyme A ◽

Inhibition Mechanism ◽

Acetate Metabolism ◽

Dependent Manner ◽

Two Component System ◽

Acetyl Coenzyme A ◽

Component System ◽

Acetyl Coenzyme ◽

Two Component

ABSTRACT The PhoP-PhoQ two-component system regulates the transcription of numerous genes in response to changes in extracellular divalent cation concentration and pH. Here we demonstrate that the Escherichia coli PhoP-PhoQ two-component system also responds to acetate. Signaling by the E. coli PhoP-PhoQ system was repressed during growth in acetate (≥25 mM) in a PhoQ-dependent manner. The periplasmic sensor domain of PhoQ was not required for acetate to repress signaling. Acetate-mediated repression of the PhoP-PhoQ system was not related to changes in the intracellular concentration of acetate metabolites such as acetyl-phosphate or acetyladenylate. Genetic analysis of acetate metabolism pathways suggested that a perturbation of acetyl coenzyme A turnover was the cause of decreased PhoP-PhoQ signaling during growth in acetate. Consistent with this hypothesis, intracellular acetyl coenzyme A levels rose during growth in the presence of exogenous acetate. Acetyl coenzyme A inhibited the autokinase activity of PhoQ in vitro, suggesting that the in vivo repressing effect may be due to a direct inhibition mechanism.

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DevR–DevS is a bona fide two-component system of Mycobacterium tuberculosis that is hypoxia-responsive in the absence of the DNA-binding domain of DevR

Microbiology ◽

10.1099/mic.0.26218-0 ◽

2004 ◽

Vol 150 (4) ◽

pp. 865-875 ◽

Cited By ~ 112

Author(s):

Deepak Kumar Saini ◽

Vandana Malhotra ◽

Deepanwita Dey ◽

Neha Pant ◽

Taposh K. Das ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Pathogenic Bacteria ◽

Response Regulator ◽

Regulatory System ◽

Site Directed Mutagenesis ◽

Phosphoryl Transfer ◽

Dependent Manner ◽

Two Component System ◽

Component System ◽

Two Component

Two-component systems play a central role in the adaptation of pathogenic bacteria to the environment prevailing within host tissues. The genes encoding the response regulator DevR (Rv3133c/DosR) and the cytoplasmic portion (DevS201) of the histidine kinase DevS (Rv3132c/DosS), a putative two-component system of Mycobacterium tuberculosis, were cloned and the protein products were overexpressed, purified and refolded as N-terminally His6-tagged proteins from Escherichia coli. DevS201 underwent autophosphorylation and participated in rapid phosphotransfer to DevR in a Mg2+-dependent manner. Chemical stability analysis and site-directed mutagenesis implicated the highly conserved residues His395 and Asp54 as the sites of phosphorylation in DevS and DevR, respectively. Mutations in Asp8 and Asp9 residues, postulated to form the acidic Mg2+-binding pocket, and the invariant Lys104 of DevR, abrogated phosphoryl transfer from DevS201 to DevR. DevR–DevS was thus established as a typical two-component regulatory system based on His-to-Asp phosphoryl transfer. Expression of the Rv3134c–devR–devS operon was induced at the RNA level in hypoxic cultures of M. tuberculosis H37Rv and was associated with an increase in the level of DevR protein. However, in a devR mutant strain expressing the N-terminal domain of DevR, induction was observed at the level of RNA expression but not at that of protein. DevS was translated independently of DevR and induction of devS transcripts was not associated with an increase in protein level in either wild-type or mutant strains, reflecting differential regulation of this locus during hypoxia.

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The ChrA-ChrS and HrrA-HrrS Signal Transduction Systems Are Required for Activation of the hmuO Promoter and Repression of the hemA Promoter in Corynebacterium diphtheriae

Infection and Immunity ◽

10.1128/iai.01821-06 ◽

2007 ◽

Vol 75 (5) ◽

pp. 2421-2431 ◽

Cited By ~ 45

Author(s):

Lori A. Bibb ◽

Carey A. Kunkle ◽

Michael P. Schmitt

Keyword(s):

Corynebacterium Diphtheriae ◽

Heme Iron ◽

Dependent Manner ◽

Two Component System ◽

Component System ◽

Regulatory Systems ◽

Component Systems ◽

Two Component ◽

Genes Encoding ◽

Two Component Systems

ABSTRACT Transcription of the Corynebacterium diphtheriae hmuO gene, which encodes a heme oxygenase involved in heme iron utilization, is activated in a heme- or hemoglobin-dependent manner in part by the two-component system ChrA-ChrS. Mutation of either the chrA or the chrS gene resulted in a marked reduction of hemoglobin-dependent activation at the hmuO promoter in C. diphtheriae; however, it was observed that significant levels of hemoglobin-dependent expression were maintained in the mutants, suggesting that an additional activator is involved in regulation. A BLAST search of the C. diphtheriae genome sequence revealed a second two-component system, encoded by DIP2268 and DIP2267, that shares similarity with ChrS and ChrA, respectively; we have designated these genes hrrS (DIP2268) and hrrA (DIP2267). Analysis of hmuO promoter expression demonstrated that hemoglobin-dependent activity was fully abolished in strains from which both the chrA-chrS and the hrrA-hrrS two-component systems were deleted. Similarly, deletion of the sensor kinase genes chrS and hrrS or the genes encoding both of the response regulators chrA and hrrA also eliminated hemoglobin-dependent activation at the hmuO promoter. We also show that the regulators ChrA-ChrS and HrrA-HrrS are involved in the hemoglobin-dependent repression of the promoter upstream of hemA, which encodes a heme biosynthesis enzyme. Evidence for cross talk between the ChrA-ChrS and HrrA-HrrS systems is presented. In conclusion, these findings demonstrate that the ChrA-ChrS and HrrA-HrrS regulatory systems are critical for full hemoglobin-dependent activation at the hmuO promoter and also suggest that these two-component systems are involved in the complex mechanism of the regulation of heme homeostasis in C. diphtheriae.

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Prevention of Surface-Associated Calcium Phosphate by thePseudomonas syringaeTwo-Component System CvsSR

Journal of Bacteriology ◽

10.1128/jb.00584-18 ◽

2019 ◽

Vol 201 (7) ◽

Cited By ~ 1

Author(s):

Maxwell R. Fishman ◽

Melanie J. Filiatrault

Keyword(s):

Calcium Phosphate ◽

Carbonic Anhydrase ◽

Pseudomonas Syringae ◽

Dependent Manner ◽

Two Component System ◽

Component System ◽

Content Type ◽

Two Component ◽

Calcium Phosphate Precipitation ◽

Calcium Precipitation

ABSTRACTCvsSR is a Ca2+-induced two-component system (TCS) in the plant pathogenPseudomonas syringaepv. tomato DC3000. Here, we discovered that CvsSR is induced by Fe3+, Zn2+, and Cd2+. However, only supplementation of Ca2+to medium resulted in rugose, opaque colonies in ΔcvsSand ΔcvsRstrains. This phenotype corresponded to formation of calcium phosphate precipitation on the surface of ΔcvsSand ΔcvsRcolonies. CvsSR regulated swarming motility inP. syringaepv. tomato in a Ca2+-dependent manner, but swarming behavior was not influenced by Fe3+, Zn2+, or Cd2+. We hypothesized that reduced swarming displayed by ΔcvsSand ΔcvsRstrains was due to precipitation of calcium phosphate on the surface of ΔcvsSand ΔcvsRcells grown on agar medium supplemented with Ca2+. By reducing the initial pH or adding glucose to the medium, calcium precipitation was inhibited, and swarming was restored to ΔcvsSand ΔcvsRstrains, suggesting that calcium precipitation influences swarming ability. Constitutive expression of a CvsSR-regulated carbonic anhydrase and a CvsSR-regulated putative sulfate major facilitator superfamily transporter in ΔcvsSand ΔcvsRstrains inhibited formation of calcium precipitates and restored the ability of ΔcvsSand ΔcvsRbacteria to swarm. Lastly, we found that glucose inhibited Ca2+-based induction of CvsSR. Hence, CvsSR is a key regulator that controls calcium precipitation on the surface of bacterial cells.IMPORTANCEBacteria are capable of precipitating and dissolving minerals. We previously reported the characterization of the two-component system CvsSR in the plant-pathogenic bacteriumPseudomonas syringae. CvsSR responds to the presence of calcium and is important for causing disease. Here, we show that CvsSR controls the ability of the bacterium to prevent calcium phosphate precipitation on the surface of cells. We also identified a carbonic anhydrase and transporter that modulate formation of surface-associated calcium precipitates. Furthermore, our results demonstrate that the ability of the bacterium to swarm is controlled by the formation and dissolution of calcium precipitates on the surface of cells. Our study describes new mechanisms for microbially induced mineralization and provides insights into the role of mineral deposits on bacterial physiology. The discoveries may lead to new technological and environmental applications.

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Staphylococcus aureus Nuclease Is an SaeRS-Dependent Virulence Factor

Infection and Immunity ◽

10.1128/iai.01242-12 ◽

2013 ◽

Vol 81 (4) ◽

pp. 1316-1324 ◽

Cited By ~ 64

Author(s):

Michael E. Olson ◽

Tyler K. Nygaard ◽

Laynez Ackermann ◽

Robert L. Watkins ◽

Oliwia W. Zurek ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Virulence Factor ◽

Dependent Manner ◽

Binding Studies ◽

Two Component System ◽

Component System ◽

Content Type ◽

Activity Measurements ◽

Two Component

ABSTRACTSeveral prominent bacterial pathogens secrete nuclease (Nuc) enzymes that have an important role in combating the host immune response. Early studies ofStaphylococcus aureusNuc attributed its regulation to theagrquorum-sensing system. However, recent microarray data have indicated thatnucis under the control of the SaeRS two-component system, which is a major regulator ofS. aureusvirulence determinants. Here we report that thenucgene is directly controlled by the SaeRS two-component system through reporter fusion, immunoblotting, Nuc activity measurements, promoter mapping, and binding studies, and additionally, we were unable identify a notable regulatory link to theagrsystem. The observed SaeRS-dependent regulation was conserved across a wide spectrum of representativeS. aureusisolates. Moreover, with community-associated methicillin-resistantS. aureus(CA MRSA) in a mouse model of peritonitis, we observedin vivoexpression of Nuc activity in an SaeRS-dependent manner and determined that Nuc is a virulence factor that is important forin vivosurvival, confirming the enzyme's role as a contributor to invasive disease. Finally, natural polymorphisms were identified in the SaeRS proteins, one of which was linked to Nuc regulation in a CA MRSA USA300 endocarditis isolate. Altogether, our findings demonstrate that Nuc is an importantS. aureusvirulence factor and part of the SaeRS regulon.

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Identification and Molecular Characterization of the Mg2+ Stimulon of Escherichia coli

Journal of Bacteriology ◽

10.1128/jb.185.13.3696-3702.2003 ◽

2003 ◽

Vol 185 (13) ◽

pp. 3696-3702 ◽

Cited By ~ 111

Author(s):

Shu Minagawa ◽

Hiroshi Ogasawara ◽

Akinori Kato ◽

Kaneyoshi Yamamoto ◽

Yoko Eguchi ◽

...

Keyword(s):

Escherichia Coli ◽

Mrna Levels ◽

Dependent Manner ◽

Direct Repeats ◽

Two Component System ◽

S1 Nuclease ◽

Component System ◽

Dnase I Footprinting ◽

Two Component

ABSTRACT Transcription profile microarray analysis in Escherichia coli was performed to identify the member genes of the Mg2+ stimulon that respond to the availability of external Mg2+ in a PhoP/PhoQ two-component system-dependent manner. The mRNA levels of W3110 in the presence of 30 mM MgCl2, WP3022 (phoP defective), and WQ3007 (phoQ defective) were compared with those of W3110 in the absence of MgCl2. The expression ratios of a total of 232 genes were <0.75 in all three strains (the supplemental data are shown at http://www.nara.kindai.ac.jp/nogei/seiken/array.html ), suggesting that the PhoP/PhoQ system is involved directly or indirectly in the transcription of these genes. Of those, 26 contained the PhoP box-like sequences with the direct repeats of (T/G)GTTTA within 500 bp upstream of the initiation codon. Furthermore, S1 nuclease assays of 26 promoters were performed to verify six new Mg2+ stimulon genes, hemL, nagA, rstAB, slyB, vboR, and yrbL, in addition to the phoPQ, mgrB, and mgtA genes reported previously. In gel shift and DNase I footprinting assays, all of these genes were found to be regulated directly by PhoP. Thus, we concluded that the phoPQ, mgrB, mgtA, hemL, nagA, rstAB, slyB, vboR, and yrbL genes make up the Mg2+ stimulon in E. coli.

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The Two-Component System CprRS Senses Cationic Peptides and Triggers Adaptive Resistance in Pseudomonas aeruginosa Independently of ParRS

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01530-12 ◽

2012 ◽

Vol 56 (12) ◽

pp. 6212-6222 ◽

Cited By ~ 73

Author(s):

Lucía Fernández ◽

Håvard Jenssen ◽

Manjeet Bains ◽

Irith Wiegand ◽

W. James Gooderham ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Antimicrobial Peptides ◽

Outer Membrane ◽

Dependent Manner ◽

Two Component System ◽

Concentration Dependent Manner ◽

Component System ◽

Content Type ◽

Wide Range ◽

Two Component

ABSTRACTCationic antimicrobial peptides pass across the outer membrane by interacting with negatively charged lipopolysaccharide (LPS), leading to outer membrane permeabilization in a process termed self-promoted uptake. Resistance can be mediated by the addition of positively charged arabinosamine through the action of thearnBCADTEFoperon. We recently described a series of two-component regulators that lead to the activation of thearnoperon after recognizing environmental signals, including low-Mg2+(PhoPQ, PmrAB) or cationic (ParRS) peptides. However, some peptides did not activate thearnoperon through ParRS. Here, we report the identification of a new two-component system, CprRS, which, upon exposure to a wide range of antimicrobial peptides, triggered the expression of the LPS modification operon. Thus, mutations in thecprRSoperon blocked the induction of thearnoperon in response to several antimicrobial peptides independently of ParRS but did not affect the response to low Mg2+. Distinct patterns ofarninduction were identified. Thus, the responses to polymyxins were abrogated by eitherparRorcprRmutations, while responses to other peptides, including indolicidin, showed differential dependency on the CprRS and ParRS systems in a concentration-dependent manner. It was further demonstrated that, following exposure to inducing antimicrobial peptides,cprRSmutants did not become adaptively resistant to polymyxins as was observed for wild-type cells. Our microarray studies demonstrated that the CprRS system controlled a quite modest regulon, indicating that it was quite specific to adaptive peptide resistance. These findings provide greater insight into the complex regulation of LPS modification inPseudomonas aeruginosa, which involves the participation of at least 4 two-component systems.

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The QseEF Two-Component System-GlmY Small RNA Regulatory Pathway Controls Swarming in Uropathogenic Proteus mirabilis

International Journal of Molecular Sciences ◽

10.3390/ijms23010487 ◽

2022 ◽

Vol 23 (1) ◽

pp. 487

Author(s):

Wen-Yuan Lin ◽

Yuan-Ju Lee ◽

Ping-Hung Yu ◽

Yi-Lin Tsai ◽

Pin-Yi She ◽

...

Keyword(s):

Small Rna ◽

Proteus Mirabilis ◽

Promoter Activity ◽

Mrna Level ◽

Site Directed Mutagenesis ◽

Dependent Manner ◽

Two Component System ◽

Swarming Motility ◽

Component System ◽

Two Component

Bacterial sensing of environmental signals through the two-component system (TCS) plays a key role in modulating virulence. In the search for the host hormone-sensing TCS, we identified a conserved qseEGF locus following glmY, a small RNA (sRNA) gene in uropathogenic Proteus mirabilis. Genes of glmY-qseE-qseG-qseF constitute an operon, and QseF binding sites were found in the glmY promoter region. Deletion of glmY or qseF resulted in reduced swarming motility and swarming-related phenotypes relative to the wild-type and the respective complemented strains. The qseF mutant had decreased glmYqseEGF promoter activity. Both glmY and qseF mutants exhibited decreased flhDC promoter activity and mRNA level, while increased rcsB mRNA level was observed in both mutants. Prediction by TargetRNA2 revealed cheA as the target of GlmY. Then, construction of the translational fusions containing various lengths of cheA 5′UTR for reporter assay and site-directed mutagenesis were performed to investigate the cheA-GlmY interaction in cheA activation. Notably, loss of glmY reduced the cheA mRNA level, and urea could inhibit swarming in a QseF-dependent manner. Altogether, this is the first report elucidating the underlying mechanisms for modulation of swarming motility by a QseEF-regulated sRNA GlmY, involving expression of cheA, rcsB and flhDC in uropathogenic P. mirabilis.

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