Abstract Sialic acid‐binding immunoglobulin‐type lectins (Siglecs) are a family of that mediate protein‐carbohydrate interactions via sialic acids attached to glycoproteins or glycolipids. Most the CD33‐related Siglecs (CD33rSiglecs), major subfamily rapidly evolving Siglecs, contain cytoplasmic signaling domain consisting immunoreceptor tyrosine‐based inhibitory motif (ITIM) and switch (ITSM) suppressive signals for lymphoid myeloid cells. While most CD33rSiglecs expressed by innate immune...

ABSTRACT RitR (formerly RR489) is an orphan two-component signal transduction response regulator in Streptococcus pneumoniae that has been shown to be required for lung pathogenicity. In the present study, by using rough strain R800, inactivation of gene ritR allele replacement reduced pathogenicity a cyclophosphamide-treated mouse model but not thigh model, suggesting role regulation tissue-specific virulence factors. Analysis changes genome-wide transcript mRNA levels associated with...

Phytochromes are a collection of bilin-containing photoreceptors that regulate diverse array processes in microorganisms and plants through photoconversion between two stable states, red light-absorbing Pr form, far Pfr form. Recently, novel set phytochrome-like chromoproteins was discovered cyanobacteria, designated here as cyanochromes, instead photoconvert blue green forms Pb Pg, respectively. Here, we show the distinctive absorption properties cyanochromes facilitated binding...

The phytochrome superfamily of photoreceptors exploits reversible light-driven changes in the bilin chromophore to initiate a variety signaling cascades. nature these alterations and how they impact protein moiety remain poorly resolved might include several species-specific routes. Here, we provide detailed picture photoconversion for photosensing cGMP phosphodiesterase/adenylyl cyclase/FhlA (GAF) domain from Thermosynechococcus elongatus (Te) PixJ, member cyanobacteriochrome clade....

We report selective phosphorylation of the DNA-binding domain Streptococcus pneumoniae transcriptional regulator RitR. RitR is annotated as a two-component response regulator, but lacks cognate His kinase neighbouring locus in genome. In addition, Asn replaces Asp at expected acceptor site. By use combinatorial phage display, we identified PhpP, S. Ser-Thr eukaryotic-like PP2C phosphatase an interacting partner interacts with phage-displayed peptide VADGMGGR which forms part active-site...

Streptococcus pneumoniae (the pneumococcus) is the major cause of bacterial pneumonia in US and worldwide. Studies have shown that differing chemical make-up between serotypes its most important virulence factor, capsule, can dictate disease severity. Here we demonstrate control capsule synthesis also critical for infection facilitated by two broadly conserved transcription factors, SpxR CpsR, through a distal cis-regulatory element name 37-CE. Strikingly, changing only three nucleotides...

We have constructed a Bacillus subtilis strain in which expression of vanH::lacZ gene fusion is regulated by VanR and VanS Enterococcus faecium. This construct allows nonpathogenic bacterial to be used as model system for studying regulation vancomycin resistance. Antibiotics enzymes that affect cell wall biosynthesis stability were tested the ability induce lacZ expression. As result, fosfomycin D-cycloserine added group peptidoglycan synthesis inhibitors shown from vanH promoter. Induction...

Photointerconversion between the red light-absorbing (Pr) form and far-red (Pfr) is central feature that allows members of phytochrome (Phy) superfamily to act as reversible switches in light perception. Whereas chromophore structure surrounding binding pocket Pr have been described, those for Pfr remained enigmatic various technical reasons. Here we describe a novel pair Phys from two thermophilic cyanobacteria, Synechococcus sp. OS-A OS-B′, overcome several these limitations. Like other...

Surface plasmon resonance (SPR) imaging measurements have been used to study the sequence specific adsorption of response regulator proteins DNA arrays constructed on gold thin films. Bacteria adapt their environment primarily through two-component signal transduction systems that consist an environmental sensor histidine kinase and a transcription activator binding protein. were fabricated from oligonucleotide sequences known regions for two regulators: OmpR, which controls gene expression...

To survive diverse host environments, the human pathogen Streptococcus pneumoniae must prevent its self-produced, extremely high levels of peroxide from reacting with intracellular iron. However, regulatory mechanism(s) by which pneumococcus accomplishes this balance remains largely enigmatic, as and other related streptococci lack all known redox-sensing transcription factors. Here we describe a two-component-derived response regulator, RitR, archetype for novel family redox sensors in...

The ability to simultaneously and more directly correlate genes with metabolite levels on a global level would provide novel information for many biological platforms yet has thus far been challenging. Here, we describe method help address this problem, which dub “Met-Seq” ( met abolite-coupled Tn seq uencing).

Two-component signaling systems are ubiquitous in bacteria, Archaea and plants play important roles sensing responding to environmental stimuli. To propagate a response the typical system employs sensory histidine kinase that phosphorylates Receiver (REC) domain on conserved aspartate (Asp) residue. Although it is known some REC domains missing this Asp residue, remains unclear as how many of these divergent exist, what their functional they regulated absence Asp. Here we have compiled all...

Abstract Rggs are a group of transcriptional regulators with diverse roles in metabolism and virulence. Here, we present work on the Rgg1518/SHP1518 quorum sensing system Streptococcus pneumoniae . The activity Rgg1518 is induced by its cognate peptide, SHP1518. In vitro analysis showed that active conditions rich galactose mannose, key nutrients during nasopharyngeal colonization. expression highly presence these sugars isogenic mutant attenuated growth mannose. When compared other Rgg...

ABSTRACT The VanRS two-component signal transduction pathway from Enterococcus faecium was reconstituted in vitro partially purified components and shown to be inhibited by the halophenyl isothiazolone LY-266,400, inhibitor A, a compound previously reduce expression of AlgR1-AlgR2 Pseudomonas aeruginosa (S. Roychoudhury, N. A. Zielinski, J. Ninfa, E. Allen, L. Jungheim, T. I. Nicas, M. Chakrabarty, Proc. Natl. Acad. Sci. USA 90:965–969, 1993). Inhibitor A attenuates phosphoryl transfer...

During its progression from the nasopharynx to other sterile and nonsterile niches of human host, Streptococcus pneumoniae must cope with changes in temperature. We hypothesized that temperature adaptation is an important facet pneumococcal survival host. Here, we evaluated effect on pneumococcus studied role glutamate dehydrogenase (GdhA) thermal associated virulence survival. Microarray analysis revealed a significant transcriptional response temperature, affecting expression 252 genes...

Abstract Efficient utilization of nutrients is crucial for microbial survival and virulence. The same nutrient may be utilized by multiple catabolic pathways, indicating that the physical chemical environments induction as well their functional roles differ. Here, we study tagatose Leloir pathways galactose catabolism human pathogen Streptococcus pneumoniae . We show potentiates pneumococcal virulence, influenced differentially concentration temperature, sialic acid downregulates catabolism....

The dodecamer peptide SLCHDSVIGWEC, named E12, was selected from a combinatorial library on the basis of its ability to bind VanR, two-component signal transduction response regulator which controls expression vancomycin resistance in Enterococcus faecium. binding E12 localized N-terminal, regulatory domain VanR contains Asp-55, residue accepts phosphoryl group His-164 activated VanS sensor kinase. along with related sequence SLAHDSIIGYLS, E12.1, found inhibit approximately P DNA segment...

The previously described Bacillus subtilis reporter strain BAU-102 is capable of detecting cell wall synthesis inhibitors that act at all stages the pathway.In addition, this compounds with hydrophobic/ surfactant activity and alternative mechanisms disruption.BAU-102 sequesters preformed β-gal in periplasm, suggesting leakage as means by which assay detects compound activities.A model proposed according to release reflects activation pathways leading autolysis.The authors also report a...

Abstract The Streptococcus pneumoniae Rgg144/SHP144 regulator‐peptide quorum sensing (QS) system is critical for nutrient utilization, oxidative stress response, and virulence. Here, we characterized this by assessing the importance of each residue within active short hydrophobic peptide (SHP) alanine‐scanning mutagenesis testing resulting peptides receptor binding activation receptor. Interestingly, several mutations had little effect on to Rgg144 but reduced transcriptional appreciably. In...

Two-component signal transduction systems are the primary means by which bacteria sense environmental change and integrate an adaptive response. In pathogenic bacteria, 2-component (TCST) kinases involved in expression of virulence antibiotic resistance. This makes bacterial TCST attractive targets for pharmacologic intervention. paper describes a fluorescence polarization assay that quantifies binding between DNA promoter segments their cognate response regulator proteins. Using Van RSTCST...

Bacterial meningitis, frequently caused by