ProQ-associated small RNAs control motility in Vibrio cholerae.

Gene regulation at the post-transcriptional level is prevalent in all domains of life. In bacteria, ProQ-like proteins have emerged as important RNA chaperones facilitating RNA stability and RNA duplex formation. In the major human pathogen Vibrio cholerae, post-transcriptional gene regulation is key for virulence, biofilm formation, and antibiotic resistance, yet the role of ProQ has not been studied.

Structure and mechanism of the Zorya anti-phage defense system.

Zorya is a recently identified and widely distributed bacterial immune system that protects bacteria from viral (phage) infections. Three Zorya subtypes have been discovered, each containing predicted membrane-embedded ZorAB complexes paired with soluble subunits that differ among Zorya subtypes, notably ZorC and ZorD in type I Zorya systems. Here, we investigate the molecular basis of Zorya defense using cryo-electron microscopy, mutagenesis, fluorescence microscopy, proteomics, and functional studies.

Bacterial motility depends on a critical flagellum length and energy-optimised assembly.

Unlabelled: The flagellum is the most complex macromolecular structure known in bacteria and comprised of around two dozen distinct proteins. The main building block of the long, external flagellar filament, flagellin, is secreted through the flagellar type-III secretion system at a remarkable rate of several tens of thousands amino acids per second, significantly surpassing the rates achieved by other pore-based protein secretion systems. The evolutionary implications and potential benefits of this high secretion rate for flagellum assembly and function, however, have remained elusive.

Fluorescent tools for the standardized work in Gram-negative bacteria.

Standardized and thoroughly characterized genetic tools are a prerequisite for studying cellular processes to ensure the reusability and consistency of experimental results. The discovery of fluorescent proteins (FPs) represents a milestone in the development of genetic reporters for monitoring transcription or protein localization in vivo. FPs have revolutionized our understanding of cellular dynamics by enabling the real-time visualization and tracking of biological processes.

Ion selectivity and rotor coupling of the Vibrio flagellar sodium-driven stator unit.

Bacteria swim using a flagellar motor that is powered by stator units. Vibrio spp. are highly motile bacteria responsible for various human diseases, the polar flagella of which are exclusively driven by sodium-dependent stator units (PomAB).

The Novel Synthetic Antibiotic BDTL049 Based on a Dendritic System Induces Lipid Domain Formation while Escaping the Cell Envelope Stress Resistance Determinants.

The threat of antimicrobial-resistant bacteria is ever increasing and over the past-decades development of novel therapeutic counter measurements have virtually come to a halt. This circumstance calls for interdisciplinary approaches to design, evaluate and validate the mode of action of novel antibacterial compounds. Hereby, carbosilane dendritic systems that exhibit antimicrobial properties have the potential to serve as synthetic and rationally designed molecules for therapeutic use.

A guide for membrane potential measurements in Gram-negative bacteria using voltage-sensitive dyes.

Transmembrane potential is one of the main bioenergetic parameters of bacterial cells, and is directly involved in energizing key cellular processes such as transport, ATP synthesis and motility. The most common approach to measure membrane potential levels is through use of voltage-sensitive fluorescent dyes. Such dyes either accumulate or are excluded from the cell in a voltage-dependent manner, which can be followed by means of fluorescence microscopy, flow cytometry, or fluorometry.

Supercoiled filaments propel them all.

In this issue of Cell, Kreutzberger and colleagues report the near-atomic-resolution, cryo-EM structures of the supercoiled filaments of both bacterial and archaeal motility machines. Despite the lack of homology, the supercoiled filament structures reveal shared fundamental features of prokaryotic locomotion and represent a prime example of convergent evolution.

Synthesis and mechanism-of-action of a novel synthetic antibiotic based on a dendritic system with bow-tie topology.

Over the course of the last decades, the continuous exposure of bacteria to antibiotics-at least in parts due to misprescription, misuse, and misdosing-has led to the widespread development of antimicrobial resistances. This development poses a threat to the available medication in losing their effectiveness in treating bacterial infections. On the drug development side, only minor advances have been made to bring forward novel therapeutics.

Phyletic Distribution and Diversification of the Phage Shock Protein Stress Response System in Bacteria and Archaea.

Maintaining cell envelope integrity is of vital importance for all microorganisms. Not surprisingly, evolution has shaped conserved protein protection networks that connect stress perception, transmembrane signal transduction, and mediation of cellular responses upon cell envelope stress. The phage shock protein (Psp) stress response is one such conserved protection network.

Characterization and mode of action analysis of black soldier fly (Hermetia illucens) larva-derived hemocytes.

With the growing importance of the black soldier fly (Hermetia illucens) for both sustainable food production and waste management as well as for science, a great demand of understanding its immune system arises. Here, we present the first description of the circulating larval hemocytes with special emphasis on uptake of microorganisms and distinguishing hemocyte types. With histological, zymographic, and cytometric methods and with a set of hemocyte binding lectins and antibodies, the hemocytes of H.

The Epipeptide Biosynthesis Locus epeXEPAB Is Widely Distributed in Firmicutes and Triggers Intrinsic Cell Envelope Stress.

The epeXEPAB (formerly yydFGHIJ) locus of Bacillus subtilis encodes a minimalistic biosynthetic pathway for a linear antimicrobial epipeptide, EpeX, which is ribosomally produced and post-translationally processed by the action of the radical-SAM epimerase, EpeE, and a membrane-anchored signal 2 peptide peptidase, EpeP. The ABC transporter EpeAB provides intrinsic immunity against self-produced EpeX, without conferring resistance against extrinsically added EpeX. EpeX specifically targets, and severely perturbs the integrity of the cytoplasmic membrane, which leads to the induction of the Lia-dependent envelope stress response.

With or without you: crosstalk between cell division and flagellum assembly.

In this issue of Developmental Cell, Siwach et al. describe a novel mechanism found in α-proteobacteria that links flagellar biosynthesis and cell division via a regulator that senses proper flagellar assembly. This spatial and temporal checkpoint control helps ensure inheritance of a flagellum during cell division.

Silver (I) -Heterocyclic Carbenes Carbosilane Dendritic Systems and Their Imidazolium-Terminated Analogues as Antibacterial Agents: Study of Their Mode of Action.

Spherical dendrimers and dendrons containing silver(I) -heterocyclic carbenes (Ag(I)-NHC) and additionally bow-tie metal-free dendritic systems were synthesized in a simple and straightforward synthetic procedure and subsequently characterized. The antibacterial activity was evaluated, and in parallel, a comparative study with the cationic analogue precursors was performed to explore the effect of silver ions in the dendritic structure. Other parameters, such as topology, generation, and hydrophobicity, of the imidazole substituents were also studied.

Amphotericin B Specifically Induces the Two-Component System LnrJK: Development of a Novel Whole-Cell Biosensor for the Detection of Amphotericin-Like Polyenes.

The rise of drug-resistant fungal pathogens urges for the development of new tools for the discovery of novel antifungal compounds. Polyene antibiotics are potent agents against fungal infections in humans and animals. They inhibit the growth of fungal cells by binding to sterols in the cytoplasmic membrane that subsequently causes pore formation and eventually results in cell death.

Development of a novel heterologous β-lactam-specific whole-cell biosensor in .

Background: Whole-cell biosensors are a powerful and easy-to-use screening tool for the fast and sensitive detection of chemical compounds, such as antibiotics. β-Lactams still represent one of the most important antibiotic groups in therapeutic use. They interfere with late stages of the bacterial cell wall biosynthesis and result in irreversible perturbations of cell division and growth, ultimately leading to cell lysis.

Network changes in patients with phobic postural vertigo.

Introduction: Functional dizziness comprises a class of dizziness disorders, including phobic postural vertigo (PPV), that cause vestibular symptoms in the absence of a structural organic origin. For this reason, functional brain mechanisms have been implicated in these disorders.

Methods: Here, functional network organization was investigated in 17 PPV patients and 18 healthy controls (HCs) during functional magnetic resonance imaging with a visual motion stimulus, data initially collected and described by Popp et al.

The Epipeptide YydF Intrinsically Triggers the Cell Envelope Stress Response of and Causes Severe Membrane Perturbations.

The Gram-positive model organism and soil bacterium naturally produces a variety of antimicrobial peptides (AMPs), including the ribosomally synthesized and post-translationally modified AMP YydF, which is encoded in the locus. The gene encodes the pre-pro-peptide, which is, in a unique manner, initially modified at two amino acid positions by the radical SAM epimerase YydG. Subsequently, the membrane-anchored putative protease YydH is thought to cleave and release the mature AMP, YydF, to the environment.

Assembly of a G-Quadruplex Repair Complex by the FANCJ DNA Helicase and the REV1 Polymerase.

The FANCJ helicase unfolds G-quadruplexes (G4s) in human cells to support DNA replication. This action is coupled to the recruitment of REV1 polymerase to synthesize DNA across from a guanine template. The precise mechanisms of these reactions remain unclear.

Coordinated Cell Death in Isogenic Bacterial Populations: Sacrificing Some for the Benefit of Many?

Antibiotics are classically perceived as biological weapons that bacteria produce to hold their ground against competing species in their natural habitat. But in the context of multicellular differentiation processes, antimicrobial compounds sometimes also play a role in intraspecies competition, resulting in the death of a sub-population of genetically identical siblings for the benefit of the population. Such a strategy is based on the diversification and hence phenotypic heterogeneity of an isogenic bacterial population.

Cortical alterations in phobic postural vertigo - a multimodal imaging approach.

Objective: Functional dizziness syndromes are among the most common diagnoses made in patients with chronic dizziness, but their underlying neural characteristics are largely unknown. The aim of this neuroimaging study was to analyze the disease-specific brain changes in patients with phobic postural vertigo (PPV).

Methods: We measured brain morphology, task response, and functional connectivity in 44 patients with PPV and 44 healthy controls.

The Bacillus BioBrick Box 2.0: expanding the genetic toolbox for the standardized work with Bacillus subtilis.

Standardized and well-characterized genetic building blocks allow the convenient assembly of novel genetic modules and devices, ensuring reusability of parts and reproducibility of experiments. In the first Bacillus subtilis-specific toolbox using the BioBrick standard, we presented integrative vectors, promoters, reporter genes and epitope tags for this Gram-positive model bacterium. With the Bacillus BioBrick Box 2.

Factors associated with acute-phase response of bisphosphonate-naïve or pretreated women with osteoporosis receiving an intravenous first dose of zoledronate or ibandronate.

Unlabelled: A first intravenous dose of bisphosphonates may be associated with an acute-phase response (APR). In bisphosphonate-naïve women with postmenopausal osteoporosis, the characteristics and frequency of APR may differ by compound. Prior bisphosphonate exposure was predictive of APR risk and severity.