Bacteria-targeted imaging using vancomycin-based positron emission tomography tracers can distinguish infection from sterile inflammation.

Introduction: Bacterial infections pose major challenges in medicine. To guide effective infection treatment, faster and more accurate diagnostic modalities are needed. Bacteria-targeted molecular imaging can meet these needs.

Activation of the general stress response sigma factor SigB prevents competence development in .

Unlabelled: Seemingly simple bacteria mount intricate adaptive responses when exposed to physical stress or nutrient limitation, and the activation of these responses is governed by complex signal transduction networks. Upon entry into the stationary growth phase, the soil bacterium may develop natural competence, form biofilms or stress-resistant cells, or ultimately trigger a cellular differentiation program leading to spore formation. Master regulators, such as Spo0A, ComK, SinR, and SigB, constantly monitor the bacterium's environment and then determine appropriate adaptive responses.

Functional and Proteomic Dissection of the Contributions of CodY, SigB and the Hibernation Promoting Factor HPF to Interactions of USA300 with Human Lung Epithelial Cells.

is a leading cause of severe pneumonia. Our recent proteomic investigations into invasion of human lung epithelial cells revealed three key adaptive responses: activation of the SigB and CodY regulons and upregulation of the hibernation-promoting factor SaHPF. Therefore, our present study aimed at a functional and proteomic dissection of the contributions of CodY, SigB and SaHPF to host invasion using transposon mutants of the methicillin-resistant USA300.

Bacillus subtilis grown in a "breathing" vessel without sparger aeration.

Here we present a "breathing" vessel consisting of expanded polytetrafluoroethylene, which allows gas exchange but no liquid permeation. The bacterial culture inside needs only agitation to promote air supply. Using this setup, a Bacillus subtilis cell factory for scyllo-inositol production grew to produce scyllo-inositol efficiently.

Functional profiling of CHAP domain-containing peptidoglycan hydrolases of Staphylococcus aureus USA300 uncovers potential targets for anti-staphylococcal therapies.

The bacterial pathogen Staphylococcus aureus employs a thick cell wall for protection against physical and chemical insults. This wall requires continuous maintenance to ensure strength and barrier integrity, but also to permit bacterial growth and division. The main cell wall component is peptidoglycan.

Nosocomial transmission of , and -carrying conferring resistance to eravacycline and omadacycline, the Netherlands, March to August 2021.

Carbapenem-resistant (CRAb) is an important pathogen causing serious nosocomial infections. We describe an outbreak of CRAb in an intensive care unit in the Netherlands in 2021. During an outbreak of non-resistant , while infection control measures were in place, CRAb isolates carrying highly similar and encoding plasmids were isolated from three patients over a period of several months.

Metabolic Profile of the Genome-Reduced Strain IIG-Bs-27-39: An Attractive Chassis for Recombinant Protein Production.

The Gram-positive bacterium is extensively used in the industry for the secretory production of proteins with commercial value. To further improve its performance, this microbe has been the subject of extensive genome engineering efforts, especially the removal of large genomic regions that are dispensable or even counterproductive. Here, we present the genome-reduced strain IIG-Bs-27-39, which was obtained through systematic deletion of mobile genetic elements, as well as genes for extracellular proteases, sporulation, flagella formation, and antibiotic production.

From the outer space to the inner cell: deconvoluting the complexity of disulfide stress responses by redox state and absolute abundance quantification of extracellular, membrane, and cytosolic proteins.

Unlabelled: Understanding cellular mechanisms of stress management relies on omics data as a valuable resource. However, the lack of absolute quantitative data on protein abundances remains a significant limitation, particularly when comparing protein abundances across different cell compartments. In this study, we aimed to gain deeper insights into the proteomic responses of the Gram-positive model bacterium to disulfide stress.

Post-translational secretion stress regulation in Bacillus subtilis is controlled by intra- and extracellular proteases.

The Gram-positive bacterium Bacillus subtilis is a prolific producer of industrial enzymes that are effectively harvested from the fermentation broth. However, the high capacity of B. subtilis for protein secretion has so far not been exploited to the full due to particular bottlenecks, including product degradation by extracellular proteases and counterproductive secretion stress responses.

TLR4 sensing of IsdB of induces a proinflammatory cytokine response via the NLRP3-caspase-1 inflammasome cascade.

The prevalence of multidrug-resistant is of global concern, and vaccines are urgently needed. The iron-regulated surface determinant protein B (IsdB) of was investigated as a vaccine candidate because of its essential role in bacterial iron acquisition but failed in clinical trials despite strong immunogenicity. Here, we reveal an unexpected second function for IsdB in pathogen-host interaction: the bacterial fitness factor IsdB triggers a strong inflammatory response in innate immune cells via Toll-like receptor 4 and the inflammasome, thus acting as a novel pathogen-associated molecular pattern of .

Let There Be Light: Genome Reduction Enables to Produce Disulfide-Bonded Luciferase.

is a major workhorse for enzyme production in industrially relevant quantities. Compared to mammalian-based expression systems, presents intrinsic advantages, such as high growth rates, high space-time yield, unique protein secretion capabilities, and low maintenance costs. However, shows clear limitations in the production of biopharmaceuticals, especially proteins from eukaryotic origin that contain multiple disulfide bonds.

A fluorogenic micrococcal nuclease-based probe for fast detection and optical imaging of Staphylococcus aureus in prosthetic joint and fracture-related infections.

Purpose: Staphylococcus aureus is the most common and impactful multi-drug resistant pathogen implicated in (periprosthetic) joint infections (PJI) and fracture-related infections (FRI). Therefore, the present proof-of-principle study was aimed at the rapid detection of S. aureus in synovial fluids and biofilms on extracted osteosynthesis materials through bacteria-targeted fluorescence imaging with the 'smart-activatable' DNA-based AttoPolyT probe.

Evaluation of Kdo-8-N incorporation into lipopolysaccharides of various strains.

8-Azido-3,8-dideoxy-α/β-d--oct-2-ulosonic acid (Kdo-8-N) is a Kdo derivative used in metabolic labeling of lipopolysaccharide (LPS) structures found on the cell membrane of Gram-negative bacteria. Several studies have reported successful labeling of LPS using Kdo-8-N and visualization of LPS by a fluorescent reagent through click chemistry on a selection of Gram-negative bacteria such as strains, , and . Motivated by the promise of Kdo-8-N to be useful in the investigation of LPS biosynthesis and cell surface labeling across different strains, we set out to explore the variability in nature and efficiency of LPS labeling using Kdo-8-N in a variety of strains and serotypes.

Diamide-based screening method for the isolation of improved oxidative stress tolerance phenotypes in mutant libraries.

During their life cycle, bacteria are exposed to a range of different stresses that need to be managed appropriately in order to ensure their growth and viability. This applies not only to bacteria in their natural habitats but also to bacteria employed in biotechnological production processes. Oxidative stress is one of these stresses that may originate either from bacterial metabolism or external factors.

Enhancing bacterial fitness and recombinant enzyme yield by engineering the quality control protease HtrA of .

In the expanding market of recombinant proteins, microbial cell factories such as are key players. Microbial cell factories experience secretion stress during high-level production of secreted proteins, which can negatively impact product yield and cell viability. The CssRS two-component system and CssRS-regulated quality control proteases HtrA and HtrB play critical roles in the secretion stress response.

Preclinical evaluation of 2-[F]fluorodeoxysorbitol as a tracer for targeted imaging of Enterobacterales infection.

Fluorine-18-fluorodeoxyglucose ([F]FDG) positron emission tomography (F-FDG-PET) is widely used for the detection of inflammatory and infectious diseases. Although this modality has proven to be a useful diagnostic tool, reliable distinction of bacterial infection from sterile inflammation or even from a malignancy remains challenging. Therefore, there is a need for bacteria-specific tracers for PET imaging that facilitate a reliable distinction of bacterial infection from other pathology.

First evaluation of a commercial multiplex PCR panel for rapid detection of pathogens associated with acute joint infections.

: prompt recognition and identification of the causative microorganism in acute septic arthritis of native and prosthetic joints is vital to increase the chances of successful treatment. The aim of this study was to independently assess the diagnostic accuracy of the multiplex BIOFIRE Joint Infection (JI) Panel (investigational use only) in synovial fluid for rapid diagnosis. : synovial fluid samples were collected at the University Medical Center Groningen from patients who had a clinical suspicion of a native septic arthritis, early acute (post-operative, within 3 months after arthroplasty) periprosthetic joint infection (PJI) or late acute (hematogenous, months after arthroplasty) PJI.

Signal Peptide Efficiency: From High-Throughput Data to Prediction and Explanation.

The passage of proteins across biological membranes via the general secretory (Sec) pathway is a universally conserved process with critical functions in cell physiology and important industrial applications. Proteins are directed into the Sec pathway by a signal peptide at their N-terminus. Estimating the impact of physicochemical signal peptide features on protein secretion levels has not been achieved so far, partially due to the extreme sequence variability of signal peptides.

Dual Action of Eeyarestatin 24 on Sec-Dependent Protein Secretion and Bacterial DNA.

Eeyarestatin 24 (ES24) is a promising new antibiotic with broad-spectrum activity. It shares structural similarity with nitrofurantoin (NFT), yet appears to have a distinct and novel mechanism: ES24 was found to inhibit SecYEG-mediated protein transport and membrane insertion in Gram-negative bacteria. However, possible additional targets have not yet been explored.

Staphylococcus aureus populations from the gut and the blood are not distinguished by virulence traits-a critical role of host barrier integrity.

Background: The opportunistic pathogen Staphylococcus aureus is an asymptomatically carried member of the microbiome of about one third of the human population at any given point in time. Body sites known to harbor S. aureus are the skin, nasopharynx, and gut.

Differential Virulence of Aggregatibacter actinomycetemcomitans Serotypes Explained by Exoproteome Heterogeneity.

Aggregatibacter actinomycetemcomitans () is a Gram-negative bacterial pathogen associated with periodontitis and nonoral diseases like rheumatoid arthritis and Alzheimer´s disease. isolates with the serotypes a, b, and c are globally most prevalent. Importantly, isolates displaying these serotypes have different clinical presentations.

Specific associations between fungi and bacteria in broncho-alveolar aspirates from mechanically ventilated intensive care unit patients.

The detection of fungi in the human respiratory tract may represent contamination, colonization or a respiratory infection. To develop effective management strategies, a more accurate and comprehensive understanding of the lung fungal microbiome is required. Therefore, the objective of the present study was to define the "mycobiome" of mechanically ventilated patients admitted to an intensive care unit (ICU) using broncho-alveolar aspirate ("sputum") samples and correlate this with clinical parameters and the bacterial microbiota.

Exploration of oxygen-mediated disinfection of medical devices reveals a high sensitivity of Pseudomonas aeruginosa to elevated oxygen levels.

The microbiological safety of medical devices is of paramount importance for patients and manufacturers alike. However, during usage medical devices will inevitably become contaminated with microorganisms, including opportunistic pathogens. This is a particular problem if these devices come in contact with body sites that carry high bacterial loads, such as the oral cavity.