YycH Regulates the Activity of the Essential YycFG Two-Component System in Bacillus subtilis

ABSTRACT Of the numerous two-component signal transduction systems found in bacteria, only a very few have proven to be essential for cell viability. Among these is the YycF (response regulator)-YycG (histidine kinase) system, which is highly conserved in and specific to the low-G+C content gram-positive bacteria. Given the pathogenic nature of several members of this class of bacteria, the YycF-YycG system has been suggested as a prime antimicrobial target. In an attempt to identify genes involved in regulation of this two-component system, a transposon mutagenesis study was designed to identify suppressors of a temperature-sensitive YycF mutant in Bacillus subtilis. Suppressors could be identified, and the prime target was the yycH gene located adjacent to yycG and within the same operon. A lacZ reporter assay revealed that YycF-regulated gene expression was elevated in a yycH strain, whereas disruption of any of the three downstream genes within the operon, yycI, yycJ, and yycK, showed no such effect. The concentrations of both YycG and YycF, assayed immunologically, remained unchanged between the wild-type and the yycH strain as determined by immunoassay. Alkaline phosphatase fusion studies showed that YycH is located external to the cell membrane, suggesting that it acts in the regulation of the sensor domain of the YycG sensor histidine kinase. The yycH strain showed a characteristic cell wall defect consistent with the previously suggested notion that the YycF-YycG system is involved in regulating cell wall homeostasis and indicating that either up- or down-regulation of YycF activity affects this homeostatic mechanism.

Download Full-text

Cell envelope gene expression in phosphate-limited Bacillus subtilis cells

Microbiology ◽

10.1099/mic.0.049205-0 ◽

2011 ◽

Vol 157 (9) ◽

pp. 2470-2484 ◽

Cited By ~ 29

Author(s):

Eric Botella ◽

Sebastian Hübner ◽

Karsten Hokamp ◽

Annette Hansen ◽

Paola Bisicchia ◽

...

Keyword(s):

Cell Wall ◽

Bacillus Subtilis ◽

Cell Envelope ◽

Expression Profiles ◽

Phosphate Limitation ◽

Envelope Gene ◽

Two Component System ◽

Cell Wall Metabolism ◽

Component System ◽

Two Component

The high phosphate content of Bacillus subtilis cell walls dictates that cell wall metabolism is an important feature of the PhoPR-mediated phosphate limitation response. Here we report the expression profiles of cell-envelope-associated and PhoPR regulon genes, determined by live cell array and transcriptome analysis, in exponentially growing and phosphate-limited B. subtilis cells. Control by the WalRK two-component system confers a unique expression profile and high level of promoter activity on the genes of its regulon with yocH and cwlO expression differing both qualitatively and quantitatively from all other autolysin-encoding genes examined. The activity of the PhoPR two-component system is restricted to the phosphate-limited state, being rapidly induced in response to the cognate stimulus, and can be sustained for an extended phosphate limitation period. Constituent promoters of the PhoPR regulon show heterogeneous induction profiles and very high promoter activities. Phosphate-limited cells also show elevated expression of the actin-like protein MreBH and reduced expression of the WapA cell wall protein and WprA cell wall protease indicating that cell wall metabolism in this state is distinct from that of exponentially growing and stationary-phase cells. The PhoPR response is very rapidly deactivated upon removal of the phosphate limitation stimulus with concomitant increased expression of cell wall metabolic genes. Moreover expression of genes encoding enzymes involved in sulphur metabolism is significantly altered in the phosphate-limited state with distinct perturbations being observed in wild-type 168 and AH024 (ΔphoPR) cells.

Download Full-text

Physiological and Molecular Characterization of a Synechocystis sp. PCC 6803 Mutant Lacking Histidine Kinase Slr1759 and Response Regulator Slr1760

Zeitschrift für Naturforschung C ◽

10.1515/znc-2006-11-1215 ◽

2006 ◽

Vol 61 (11-12) ◽

pp. 865-878 ◽

Cited By ~ 2

Author(s):

Anke Nodop ◽

Iwane Suzuki ◽

Aiko Barsch ◽

Ann-Kristin Schröder ◽

Karsten Niehaus ◽

...

Keyword(s):

Histidine Kinase ◽

Ph Value ◽

Response Regulator ◽

Two Component System ◽

Component System ◽

Bg11 Medium ◽

Two Component ◽

Metabolic Activities ◽

Synechocystis Sp ◽

Pcc 6803

Abstract The hybrid sensory histidine kinase Slr1759 of the cyanobacterium Synechocystis sp. strain PCC 6803 contains multiple sensory domains and a multi-step phosphorelay system. Immuno blot analysis provided evidence that the histidine kinase Slr1759 is associated with the cytoplasmic membrane. The gene slr1759 is part of an operon together with slr1760, encoding a response regulator. A comparative investigation was performed on Synechocystis sp. strain PCC 6803 wild type (WT) and an insertionally inactivated slr1759-mutant (Hik14) which also lacks the transcript for the response regulator Slr1760. The mutant Hik14 grew significantly slower than WT in the early growth phase, when both were inoculated with a low cell density into BG11 medium without additional buffer and when aerated with air enriched with 2% CO2. Since the aeration with CO2-enriched air results in a decrease of the pH value in the medium, the growth experiments indicated that Hik14 is not able to adjust its metabolic activities as rapidly as WT to compensate for a larger decrease of the pH value in the medium. No significant differences in growth between Hik14 and WT were observed when cells were inoculated with a higher cell density in BG11 medium or when the BG11 medium contained 50 mm Epps-NaOH, pH 7.5, to prevent the pH drop. This Hik14 phenotype has so far only been seen under the above defined growth condition. Results of photosynthetic activity measurements as well as Northern blot-, immuno blot-, and metabolite analyses suggest that the two-component system Slr1759/Slr1760 has a function in the coordination of several metabolic activities which is in good agreement with the complex domain structure of Slr1759. The direct targets of this two-component system have so far not been identified.

Download Full-text

Mcs4, a Two-Component System Response Regulator Homologue, Regulates the Schizosaccharomyces pombe Cell Cycle Control

Genetics ◽

10.1093/genetics/147.3.1043 ◽

1997 ◽

Vol 147 (3) ◽

pp. 1043-1051 ◽

Cited By ~ 2

Author(s):

Guillaume Cottarel

Keyword(s):

Cell Cycle ◽

Schizosaccharomyces Pombe ◽

Response Regulator ◽

Cell Cycle Control ◽

Mitotic Catastrophe ◽

System Response ◽

Temperature Sensitive ◽

Two Component System ◽

Component System ◽

Two Component

The Schizosaccharomyces pombe cdc2-3w weel-50 double mutant displays a temperature-sensitive lethal phenotype termed mitotic catastrophe. Six mitotic catastrophe suppressor (mcs1-6) genes were identified in a genetic screen designed to identify regulators of cdc2. Mutations in mcs1-6 suppress the cdc2-3w weel-50 temperature-sensitive growth defect. Here, the cloning of mcs4 is described. The mcs4 gene product displays significant sequence homology to members of the two-component system response regulator protein family. Strains carrying the mcs4 and cdc25 mutations display a synthetic osmotic lethal phenotype along with an inability to grow on minimal synthetic medium. These phenotypes are suppressed by a mutation in wee1. In addition, the wis1 gene, encoding a stress-activated mitogen-activated protein kinase kinase, was identified as a dosage suppressor in this screen. These findings link the two-component signal transduction system to stress response and cell cycle control in S. pombe.

Download Full-text

Diversity of two-component systems: insights into the signal transduction mechanism by the Staphylococcus aureus two-component system GraSR

F1000Research ◽

10.12688/f1000research.5512.2 ◽

2014 ◽

Vol 3 ◽

pp. 252 ◽

Cited By ~ 4

Author(s):

Uzma Muzamal ◽

Daniel Gomez ◽

Fenika Kapadia ◽

Dasantila Golemi-Kotra

Keyword(s):

Signal Transduction ◽

Staphylococcus Aureus ◽

Abc Transporter ◽

Histidine Kinase ◽

Response Regulator ◽

Two Component System ◽

Component System ◽

Transduction Mechanism ◽

Two Component ◽

Auxiliary Protein

The response to cationic antimicrobial peptides (CAMPs) in Staphylococcus aureus relies on a two-component system (TCS), GraSR, an auxiliary protein GraX and an ATP-binding cassette (ABC) transporter, VraF/G. To understand the signal transduction mechanism by GraSR, we investigated the kinase activity of the cytoplasmic domain of histidine kinase GraS and the interaction with its cognate response regulator GraR. We also investigated interactions among the auxiliary protein GraX, GraS/R and the ATPase protein of the ABC transporter, VraF. We found that GraS lacks autophosphorylation activity, unlike a similar histidine kinase, BceS, of Bacillus subtilis. In addition, the interaction between GraS and GraR is very weak in comparison to the stronger interaction observed between BceS and its conjugated response regulator, BceR, suggesting that CAMP signaling may not flow directly from GraS to GraR. We found that the auxiliary protein GraX interacts with VraF and GraR, and requires the histidine phosphotransfer and dimerization domain of GraS to interact with this protein. Further, VraF requires the GraS region that connects the membrane-bound domain with the cytoplasmic domain of this protein for interaction with GraS. The interactions of GraX with GraS/R and VraF indicate that GraX may serve as a scaffold to bring these proteins in close proximity to GraS, plausibly to facilitate activation of GraS to ultimately transduce the signal to GraR.

Download Full-text

Overexpression of the Response RegulatorevgA of the Two-Component Signal Transduction System Modulates Multidrug Resistance Conferred by Multidrug Resistance Transporters

Journal of Bacteriology ◽

10.1128/jb.183.4.1455-1458.2001 ◽

2001 ◽

Vol 183 (4) ◽

pp. 1455-1458 ◽

Cited By ~ 82

Author(s):

Kunihiko Nishino ◽

Akihito Yamaguchi

Keyword(s):

Escherichia Coli ◽

Multidrug Resistance ◽

Response Regulator ◽

Multidrug Efflux ◽

Signal Transduction System ◽

Two Component System ◽

Component System ◽

Two Component ◽

Two Component Signal Transduction ◽

Multidrug Resistance Transporters

ABSTRACT Overexpression of evgA, a response regulator of a two-component system, increased multidrug efflux in Escherichia coli. Since overexpression of the emrKY operon, which is controlled by evgAS, could account only for deoxycholate resistance, the evgAS locus apparently controls expression of at least one other multidrug efflux operon.

Download Full-text

Intra- and intermolecular domain interactions among novel two-component system proteins coded by Rv0600c, Rv0601c and Rv0602c of Mycobacterium tuberculosis

Microbiology ◽

10.1099/mic.0.019059-0 ◽

2009 ◽

Vol 155 (3) ◽

pp. 772-779 ◽

Cited By ~ 9

Author(s):

Rashmi Shrivastava ◽

Ananta Kumar Ghosh ◽

Amit Kumar Das

Keyword(s):

Mycobacterium Tuberculosis ◽

Histidine Kinase ◽

Response Regulator ◽

Dominant Role ◽

Phosphoryl Group ◽

Two Component System ◽

Component System ◽

Two Component ◽

Domain Interactions ◽

Cognate Response Regulator

Two-component signal transduction pathways comprising a histidine kinase and its cognate response regulator play a dominant role in the adaptation of Mycobacterium tuberculosis to its host, and its virulence, pathogenicity and latency. Autophosphorylation occurs at a conserved histidine of the histidine kinase and subsequently the phosphoryl group is transferred to the conserved aspartate of its cognate response regulator. Among the twelve two-component systems of M. tuberculosis, Rv0600c (HK1), Rv0601c (HK2) and Rv0602c (TcrA) are annotated as a unique three-protein two-component system. HK1 contains an ATP-binding domain, and HK2, a novel Hpt mono-domain protein, contains the conserved phosphorylable histidine residue. HK1 and HK2 complement each other's functions. Interactions among different domains of the HK1, HK2 and TcrA proteins were studied using a yeast two-hybrid system. Self-interaction was observed for HK2 but not for HK1 or TcrA. HK2 was found to interact reasonably well with both HK1 and TcrA, but HK1 interacted weakly with TcrA. The conserved aspartate-containing receiver domain of TcrA interacted well with HK2 but not with HK1. These results suggest the existence of a novel signalling mechanism amongst HK1–HK2–TcrA, and a model for this mechanism is proposed.

Download Full-text

Diversity of two-component systems: insights into the signal transduction mechanism by the Staphylococcus aureus two-component system GraSR

F1000Research ◽

10.12688/f1000research.5512.1 ◽

2014 ◽

Vol 3 ◽

pp. 252 ◽

Cited By ~ 7

Author(s):

Uzma Muzamal ◽

Daniel Gomez ◽

Fenika Kapadia ◽

Dasantila Golemi-Kotra

Keyword(s):

Signal Transduction ◽

Staphylococcus Aureus ◽

Abc Transporter ◽

Histidine Kinase ◽

Response Regulator ◽

Two Component System ◽

Component System ◽

Transduction Mechanism ◽

Two Component ◽

Auxiliary Protein

Download Full-text

YycH and YycI Interact To Regulate the Essential YycFG Two-Component System in Bacillus subtilis

Journal of Bacteriology ◽

10.1128/jb.01936-06 ◽

2007 ◽

Vol 189 (8) ◽

pp. 3280-3289 ◽

Cited By ~ 83

Author(s):

Hendrik Szurmant ◽

Michael A. Mohan ◽

P. Michael Imus ◽

James A. Hoch

Keyword(s):

Signal Transduction ◽

Cell Wall ◽

Bacillus Subtilis ◽

Membrane Integrity ◽

Direct Result ◽

Signal Transduction System ◽

Two Component System ◽

Component System ◽

Growth Defects ◽

Two Component

ABSTRACT The YycFG two-component system is the only signal transduction system in Bacillus subtilis known to be essential for cell viability. This system is highly conserved in low-G+C gram-positive bacteria, regulating important processes such as cell wall homeostasis, cell membrane integrity, and cell division. Four other genes, yycHIJK, are organized within the same operon with yycF and yycG in B. subtilis. Recently, it was shown that the product of one of these genes, the YycH protein, regulated the activity of this signal transduction system, whereas no function could be assigned to the other genes. Results presented here show that YycI and YycH proteins interact to control the activity of the YycG kinase. Strains carrying individual in-frame deletion of the yycI and yycH coding sequences were constructed and showed identical phenotypes, namely a 10-fold-elevated expression of the YycF-dependent gene yocH, growth defects, as well as a cell wall defect. Cell wall and growth defects were a direct result of overregulation of the YycF regulon, since a strain overexpressing YycF showed phenotypes similar to those of yycH and yycI deletion strains. Both YycI and YycH proteins are localized outside the cytoplasm and attached to the membrane by an N-terminal transmembrane sequence. Bacterial two-hybrid data showed that the YycH, YycI, and the kinase YycG form a ternary complex. The data suggest that YycH and YycI control the activity of YycG in the periplasm and that this control is crucial in regulating important cellular processes.

Download Full-text

Bacteriocin production in Streptococcus gallolyticus is controlled by a complex 4-component regulatory system with activator and anti-activator activities

10.1101/2020.06.04.131722 ◽

2020 ◽

Author(s):

Alexis Proutière ◽

Bruno Périchon ◽

Laurence du Merle ◽

Hugo Varet ◽

Patrick Trieu-Cuot ◽

...

Keyword(s):

Histidine Kinase ◽

Response Regulator ◽

Regulatory System ◽

Opportunistic Pathogen ◽

Bacteriocin Production ◽

Two Component System ◽

Promoter Regions ◽

Component System ◽

Streptococcus Gallolyticus ◽

Two Component

AbstractBacteriocins are natural antimicrobial peptides produced by bacteria to kill closely related competitors. The opportunistic pathogen Streptococcus gallolyticus (Sgg) was recently shown to outcompete commensal enterococci of the murine microbiota in tumoral conditions thanks to the production of a two-peptide bacteriocin named gallocin. We here identified 4 genes involved in the regulatory control of gallocin in Sgg UCN34, respectively encoding a histidine kinase/response regulator two-component system (BlpH/BlpR), a secreted peptide (GSP), and a putative regulator of unknown function (BlpS). While BlpR is a typical 243-aa response regulator possessing a phospho-receiver domain and a LytTR DNA-binding domain, BlpS is a 108-aa protein containing only a LytTR domain. Our results showed that the secreted peptide GSP activates the dedicated two-component system BlpH/BlpR to induce gallocin transcription. A genome-wide transcriptome analysis indicates that this regulatory system (GSP-BlpH/BlpR) is highly specific for bacteriocin production. Importantly, as opposed to BlpR, BlpS was shown to repress gallocin gene transcription. A conserved operator DNA sequence of 30-bp was found in all promoter regions regulated by BlpR and BlpS. EMSA assays showed direct and specific binding of the two gallocin regulators to various regulated promoter regions in a dose dependent manner. Gallocin expression appears tightly controlled in Sgg by quorum sensing and antagonistic activity of 2 LytTR-containing proteins.SignificanceStreptococcus gallolyticus (Sgg), formely known as S. bovis biotype I, is an opportunistic pathogen causing septicemia and endocarditis in the elderly often associated with asymptomatic colonic neoplasia. We previously showed that Sgg produces a bacteriocin, termed gallocin, enabling colonization of the colon in tumoral conditions by outcompeting commensal members of the gut. Here we characterized a 4-component regulatory system that regulates gallocin transcription, which is activated by the response regulator BlpR. BlpR itself is activated by a quorum sensing peptide GSP and a dedicated histidine kinase BlpH. Interestingly, BlpS, a small DNA-binding protein co-transcribed with BlpR was found to repress gallocin genes transcription, likely by antagonizing BlpR. Understanding gallocin regulation is crucial to prevent Sgg colon colonization in tumoral conditions.

Download Full-text

Regulation of Resistance in Vancomycin-Resistant Enterococci: The VanRS Two-Component System

Microorganisms ◽

10.3390/microorganisms9102026 ◽

2021 ◽

Vol 9 (10) ◽

pp. 2026

Author(s):

Alexandra A. Guffey ◽

Patrick J. Loll

Keyword(s):

Histidine Kinase ◽

Response Regulator ◽

Treatment Options ◽

Vancomycin Resistance ◽

Two Component System ◽

Component System ◽

Sensor Histidine Kinase ◽

Vancomycin Resistant Enterococci ◽

Two Component ◽

Vancomycin Resistant

Vancomycin-resistant enterococci (VRE) are a serious threat to human health, with few treatment options being available. New therapeutics are urgently needed to relieve the health and economic burdens presented by VRE. A potential target for new therapeutics is the VanRS two-component system, which regulates the expression of vancomycin resistance in VRE. VanS is a sensor histidine kinase that detects vancomycin and in turn activates VanR; VanR is a response regulator that, when activated, directs expression of vancomycin-resistance genes. This review of VanRS examines how the expression of vancomycin resistance is regulated, and provides an update on one of the field’s most pressing questions: How does VanS sense vancomycin?

Download Full-text