Citrate serves as a signal molecule to modulate carbon metabolism and iron homeostasis in Staphylococcus aureus.

Pathogenic bacteria's metabolic adaptation for survival and proliferation within hosts is a crucial aspect of bacterial pathogenesis. Here, we demonstrate that citrate, the first intermediate of the tricarboxylic acid (TCA) cycle, plays a key role as a regulator of gene expression in Staphylococcus aureus. We show that citrate activates the transcriptional regulator CcpE and thus modulates the expression of numerous genes involved in key cellular pathways such as central carbon metabolism, iron uptake and the synthesis and export of virulence factors.

Modular, automated synthesis of spirocyclic tetrahydronaphthyridines from primary alkylamines.

Spirocyclic tetrahydronaphthyridines (THNs) are valuable scaffolds for drug discovery campaigns, but access to this 3D chemical space is hampered by a lack of modular and scalable synthetic methods. We hereby report an automated, continuous flow synthesis of α-alkylated and spirocyclic 1,2,3,4-tetrahydro-1,8-naphthyridines ("1,8-THNs"), in addition to their regioisomeric 1,6-THN analogues, from abundant primary amine feedstocks. An annulative disconnection approach based on photoredox-catalysed hydroaminoalkylation (HAA) of halogenated vinylpyridines is sequenced in combination with intramolecular SAr N-arylation.

Advances in cis-element- and natural variation-mediated transcriptional regulation and applications in gene editing of major crops.

Transcriptional regulation is crucial to control of gene expression. Both spatio-temporal expression patterns and expression levels of genes are determined by the interaction between cis-acting elements and trans-acting factors. Numerous studies have focused on the trans-acting factors that mediate transcriptional regulatory networks.

Diversification of three genes and their roles in sodium exclusion in bread wheat ( L.).

The ability to exclude sodium from the shoot is a crucial feature of salinity tolerance in bread wheat ( L.). The plasma membrane sodium/proton exchanger salt-overly-sensitive 1 (SOS1) is a critical Na.

Modulation of MRSA virulence gene expression by the wall teichoic acid enzyme TarO.

Phenol-soluble modulins (PSMs) and Staphylococcal protein A (SpA) are key virulence determinants for community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA), an important human pathogen that causes a wide range of diseases. Here, using chemical and genetic approaches, we show that inhibition of TarO, the first enzyme in the wall teichoic acid (WTA) biosynthetic pathway, decreases the expression of genes encoding PSMs and SpA in the prototypical CA-MRSA strain USA300 LAC. Mechanistically, these effects are linked to the activation of VraRS two-component system that directly represses the expression of accessory gene regulator (agr) locus and spa.

A novel copper-sensing two-component system for inducing Dsb gene expression in bacteria.

In nature, bacteria must sense copper and tightly regulate gene expression to evade copper toxicity. Here, we identify a new copper-responsive two-component system named DsbRS in the important human pathogen Pseudomonas aeruginosa; in this system, DsbS is a sensor histidine kinase, and DsbR, its cognate response regulator, directly induces the transcription of genes involved in protein disulfide bond formation (Dsb) (i.e.

The life cycle of Hyalomma scupense (Acari: Ixodidae) under laboratory conditions.

The life cycle of Hyalomma scupense on rabbit hosts was investigated under laboratory conditions. Hy. scupense exhibited one- and two-host life cycles of 163.

Ratiometric fluorescent sensors for nitrite detection in the environment based on carbon dot/Rhodamine B systems.

A novel carbon dot/Rhodamine B-based ratiometric fluorescent probe was developed for a highly sensitivity and selective detection of nitrite (NO ). The probe showed colour changes from blue to orange under ultraviolet light in response to NO with a detection limit as low as 67 nM in the range of 0 to 40 μM. A ratiometric fluorescent test paper was successfully prepared using the probe solution, which demonstrated its feasibility towards a rapid and semi-quantitative detection of NO in real samples.

Novel niclosamide-derived adjuvants elevating the efficacy of polymyxin B against MDR Pseudomonas aeruginosa DK2.

Pseudomonas aeruginosa (P. aeruginosa) DK2 is a multidrug-resistant (MDR) gram-negative bacterial pathogen, being observed serious resistance to the 'last-resort' antibiotic, polymyxin B (PB). Combination therapies with adjuvants have emerged as effective strategies to reactivate the antibiotics resisted by MDR bacteria.

The Impact of Sustainable Transformational Leadership on Sustainable Innovation Ambidexterity: Empirical Evidence From Green Building Industries of China.

Recognizing that building work will continually encompass, to a certain degree, unfavorable ecological consequences, green building has been encouraged and advocated as a managerial concept to progress in the construction segment. This research created a conceptual model that analyzed whether sustainable transformational leadership (STL) supported sustainable innovation ambidexterity (SIA) in green building industries. This research model was based on organizational support theory, hope theory, social cognitive theory, and attribution theory.

Ratiometric fluorescence sensor for sensitive detection of inorganic phosphate in environmental samples.

Fast, simple, and low-cost on-site visualized detection of inorganic phosphate (Pi) is in great demand since phosphate is the major reason of eutrophication. In this work, a ratiometric fluorescent probe composed by green carbon dots (GCDs) and red carbon dots (RCDs) has been established for high-sensitivity and selective sensing of Pi. A trend of color change from red to green is observed for the detection of Pi under ultraviolet light and the detection limit is 0.

Histamine activates HinK to promote the virulence of Pseudomonas aeruginosa.

During infections, bacteria stimulate host cells to produce and release histamine, which is a key mediator of vital cellular processes in animals. However, the mechanisms underlying the bacterial cell's ability to sense and respond to histamine are poorly understood. Herein, we show that HinK, a LysR-type transcriptional regulator, is required to evoke responses to histamine in Pseudomonas aeruginosa, an important human pathogen.

Glucose-Binding of Periplasmic Protein GltB Activates GtrS-GltR Two-Component System in .

A two-component system GtrS-GltR is required for glucose transport activity in and plays a key role during -host interactions. However, the mechanism of action of GtrS-GltR has not been definitively established. Here, we show that , which encodes a periplasmic glucose binding protein, is essential for the glucose-induced activation of GtrS-GltR in .

Genome-Wide Mapping Reveals Complex Regulatory Activities of BfmR in .

BfmR is a response regulator that modulates diverse pathogenic phenotypes and induces an acute-to-chronic virulence switch in , an important human pathogen causing serious nosocomial infections. However, the mechanisms of action of BfmR remain largely unknown. Here, using chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq), we showed that 174 chromosomal regions of MPAO1 genome were highly enriched by coimmunoprecipitation with a C-terminal Flag-tagged BfmR.

Mutation-induced remodeling of the BfmRS two-component system in clinical isolates.

Genetic mutations are a primary driving force behind the adaptive evolution of bacterial pathogens. Multiple clinical isolates of , an important human pathogen, have naturally evolved one or more missense mutations in , which encodes the sensor histidine kinase of the BfmRS two-component system (TCS). A mutant BfmS protein containing both the L181P and E376Q substitutions increased the phosphorylation and thus the transcriptional regulatory activity of its cognate downstream response regulator, BfmR.

Alteration of protein homeostasis mediates the interaction of Pseudomonas aeruginosa with Staphylococcus aureus.

Intracellular protein degradation is essential for the survival of all organisms, but its role in interspecies interaction is unknown. Here, we show that the ClpXP protease of Pseudomonas aeruginosa suppresses its antimicrobial activity against Staphylococcus aureus, a common pathogen co-isolated with P. aeruginosa from polymicrobial human infections.

Recent advances in the synthesis and application of copper nanomaterials based on various DNA scaffolds.

Fluorescent copper nanomaterials (CuNMs), including copper nanoparticles (CuNPs) and copper nanoclusters (CuNCs), become more and more popular with the abundant raw materials and low cost. A wide range of applications has been explored due to their fascinating properties such as low toxicity, remarkable water solubility, facile synthesis, large Stokes shifts, and good biocompatibility. As a kind of genetic material, DNA exhibits its molecular recognition function and diversity.

Allelic variation of high molecular weight glutenin subunits of bread wheat in Hebei province of China.

In common wheat ( L.), allelic variations of Glu-1 loci have important influences on grain end-use quality. The allelic variations in high molecular weight glutenin subunits (HMW-GSs) were identified in 151 hexaploid wheat varieties representing a historical trend in the cultivars introduced or released inHebei province ofChina fromthe years 1970s to 2010s.

Design, synthesis and structure-activity relationship evaluation of novel LpxC inhibitors as Gram-negative antibacterial agents.

LpxC inhibitors are new-type antibacterial agents developed in the last twenty years, mainly against Gram-negative bacteria infections. To develop novel LpxC inhibitors with good antibacterial activities and biological metabolism, we summarized the basic skeleton of reported LpxC inhibitors, designed and synthesized several series of compounds and tested their antibacterial activities against Escherichial coli and Pseudomonas aeruginosa in vitro. Structure-activity relationships have been discussed in this article.

Misoprostol versus ergometrine-oxytocin for preventing postpartum haemorrhage: a systematic review and meta-analysis of randomized controlled trials.

Objective: To compare the effects of misoprostol versus ergometrine-oxytocin for postpartum haemorrhage (PPH) prevention, and provide important evidence to choose optimal agents for preventing PPH in developing countries.

Methods: The Cochrane Central Register of Controlled Trials, PubMed, EMbase, and ClinicalTrails.gov were searched from inception to 1st January 2016.

Small-molecule targeting of a diapophytoene desaturase inhibits S. aureus virulence.

The surge of antibiotic resistance in Staphylococcus aureus has created a dire need for innovative anti-infective agents that attack new targets, to overcome resistance. In S. aureus, carotenoid pigment is an important virulence factor because it shields the bacterium from host oxidant killing.

A label-free fluorescent molecular beacon based on DNA-Ag nanoclusters for the construction of versatile Biosensors.

In this paper, we developed a simple, low-cost and sensitive DNA sequences detection biosensor based on a label-free molecular beacon (MB) whose DNA hairpin structure terminal has a guanine-rich sequence that can enhance fluorescence of silver nanoclusters (Ag NCs). Without hybridization between hairpin probe and target DNA, the Ag NCs presented bright fluorescence for the proximity of guanine-rich sequences (GRSs). After binding with target DNA, the hairpin shape was destroyed which results in a decrease of the Ag NCs fluorescence intensity.

The Crc protein participates in down-regulation of the Lon gene to promote rhamnolipid production and rhl quorum sensing in Pseudomonas aeruginosa.

Rhamnolipid acts as a virulence factor during Pseudomonas aeruginosa infection. Here, we show that deletion of the catabolite repression control (crc) gene in P. aeruginosa leads to a rhamnolipid-negative phenotype.

A novel signal transduction pathway that modulates rhl quorum sensing and bacterial virulence in Pseudomonas aeruginosa.

The rhl quorum-sensing (QS) system plays critical roles in the pathogenesis of P. aeruginosa. However, the regulatory effects that occur directly upstream of the rhl QS system are poorly understood.

A novel homogeneous label-free aptasensor for 2,4,6-trinitrotoluene detection based on an assembly strategy of electrochemiluminescent graphene oxide with gold nanoparticles and aptamer.

We report a novel homogeneous label-free aptasensor for 2,4,6-trinitrotoluene (TNT) detection based on an assembly strategy of electrochemiluminescent graphene oxide (GO) with gold nanoparticles (AuNPs) and aptamer. In this sensing strategy, the anti-TNT aptamer was first assembled with AuNPs to form aptamer-AuNPs. Then ruthenium(II) complex functionalized GO (denoted as Ru-GO) was assembled with aptamer-AuNPs by electrostatic interaction.