Non-viral vaccination through cationic guanidium polymer-pDNA polyplex mediated gene transfer.

Vaccination through cellular transfection of nucleotide-based vaccines is a powerful approach to combatting disease. Plasmid DNA (pDNA) vaccines are particularly promising vectors for non-viral immunomodulation that afford high degrees of potency and flexibility. Versatile guanidinium-functionalized poly(oxanorbornene)imide (PONI-Guan) homopolymers were used to facilitate non-disruptive pDNA condensation into discrete polyplexes, enabling efficient transfection of endothelial cells and HD-11 macrophages.

Combined Transcriptome Sequencing of and Infected Pig Lung Tissue Reveals Up-Regulation of Bacterial F1-Like ATPase and Down-Regulation of the P102 Cilium Adhesin .

() causes enzootic pneumonia in pigs but it is still largely unknown which host-pathogen interactions enable persistent infection and cause disease. In this study, we analyzed the host and bacterial transcriptomes during infection using RNA sequencing. Comparison of the transcriptome of lung lesion tissue from infected pigs with lung tissue from non-infected animals, identified 424 differentially expressed genes (FDR < 0.

Risk-Based Bioengineering Strategies for Reliable Bacterial Vaccine Production.

Design of a reliable process for bacterial antigen production requires understanding of and control over critical process parameters. Current methods for process design use extensive screening experiments for determining ranges of critical process parameters yet fail to give clear insights into how they influence antigen potency. To address this gap, we propose to apply constraint-based, genome-scale metabolic models to reduce the need of experimental screening for strain selection and to optimize strains based on model driven iterative Design-Build-Test-Learn (DBTL) cycles.

The antibody response in the bovine mammary gland is influenced by the adjuvant and the site of subcutaneous vaccination.

Intramammary infections in cattle resulting in mastitis have detrimental effects on cows' well-being, lifespan and milk production. In the host defense against S. aureus mastitis antibodies are thought to play an important role.

Metabolic modeling of energy balances in Mycoplasma hyopneumoniae shows that pyruvate addition increases growth rate.

Mycoplasma hyopneumoniae is cultured on large-scale to produce antigen for inactivated whole-cell vaccines against respiratory disease in pigs. However, the fastidious nutrient requirements of this minimal bacterium and the low growth rate make it challenging to reach sufficient biomass yield for antigen production. In this study, we sequenced the genome of M.

Persistence of Functional Protein Domains in Mycoplasma Species and their Role in Host Specificity and Synthetic Minimal Life.

Mycoplasmas are the smallest self-replicating organisms and obligate parasites of a specific vertebrate host. An in-depth analysis of the functional capabilities of mycoplasma species is fundamental to understand how some of simplest forms of life on Earth succeeded in subverting complex hosts with highly sophisticated immune systems. In this study we present a genome-scale comparison, focused on identification of functional protein domains, of 80 publically available mycoplasma genomes which were consistently re-annotated using a standardized annotation pipeline embedded in a semantic framework to keep track of the data provenance.

Platelet endothelial cell adhesion molecule-1, a putative receptor for the adhesion of Streptococcus pneumoniae to the vascular endothelium of the blood-brain barrier.

The Gram-positive bacterium Streptococcus pneumoniae is the main causative agent of bacterial meningitis. S. pneumoniae is thought to invade the central nervous system via the bloodstream by crossing the vascular endothelium of the blood-brain barrier.

Streptococcus pneumoniae Interacts with pIgR expressed by the brain microvascular endothelium but does not co-localize with PAF receptor.

Streptococcus pneumoniae is thought to adhere to the blood-brain barrier (BBB) endothelium prior to causing meningitis. The platelet activating factor receptor (PAFR) has been implicated in this adhesion but there is a paucity of data demonstrating direct binding of the bacteria to PAFR. Additionally, studies that inhibit PAFR strongly suggest that alternative receptors for pneumococci are present on the endothelium.

Influence of impaired lipoprotein biogenesis on surface and exoproteome of Streptococcus pneumoniae.

Surface proteins are important for the fitness and virulence of the Gram-positive pathogen Streptococcus pneumoniae. They are crucial for interaction of the pathogen with its human host during infection. Therefore, the analysis of the pneumococcal surface proteome is an important task that requires powerful tools.

Interactions between blood-borne Streptococcus pneumoniae and the blood-brain barrier preceding meningitis.

Streptococcus pneumoniae (the pneumococcus) is a Gram-positive bacterium and the predominant cause of bacterial meningitis. Meningitis is thought to occur as the result of pneumococci crossing the blood-brain barrier to invade the Central Nervous System (CNS); yet little is known about the steps preceding immediate disease development. To study the interactions between pneumococci and the vascular endothelium of the blood-brain barrier prior to meningitis we used an established bacteremia-derived meningitis model in combination with immunofluorescent imaging.

Pyruvate oxidase influences the sugar utilization pattern and capsule production in Streptococcus pneumoniae.

Pyruvate oxidase is a key function in the metabolism and lifestyle of many lactic acid bacteria and its activity depends on the presence of environmental oxygen. In Streptococcus pneumoniae the protein has been suggested to play a major role in metabolism and has been implicated in virulence, oxidative stress survival and death in stationary phase. Under semi-aerobic conditions, transcriptomic and metabolite profiling analysis of a spxB mutant grown on glucose showed minor changes compared to the wild type, apart from the significant induction of two operons involved in carbohydrate uptake and processing.

Streptococcus pneumoniae invades endothelial host cells via multiple pathways and is killed in a lysosome dependent manner.

Streptococcus pneumoniae is one of the major causative agents of pneumonia, sepsis, meningitis and other morbidities. In spite of its heavy disease burden, surprisingly little is known about the mechanisms involved in the switch of life style, from commensal colonizer of the nasopharynx to invasive pathogen. In vitro experiments, and mouse models have shown that S.

Signalling or binding: the role of the platelet-activating factor receptor in invasive pneumococcal disease.

Streptococcus pneumoniae (the pneumococcus) is an opportunistic human pathogen, which causes serious invasive disease such as pneumonia, bacteraemia and meningitis. The interaction of the bacteria with host receptors precedes the development of invasive disease. One host receptor implicated in pneumococcal adhesion to, invasion of and ultimately translocation of cell layers is the platelet-activating factor receptor (PAFR).

Streptococcus pneumoniae and reactive oxygen species: an unusual approach to living with radicals.

Streptococcus pneumoniae, an aerotolerant anaerobe, is an important human pathogen that regularly encounters toxic oxygen radicals from the atmosphere and from the host metabolism and immune system. Additionally, S. pneumoniae produces large amounts of H2O2 as a byproduct of its metabolism, which contributes to its virulence but also has adverse effects on its biology.

Pneumococcal gene complex involved in resistance to extracellular oxidative stress.

Streptococcus pneumoniae is a gram-positive bacterium which is a member of the normal human nasopharyngeal flora but can also cause serious disease such as pneumonia, bacteremia, and meningitis. Throughout its life cycle, S. pneumoniae is exposed to significant oxidative stress derived from endogenously produced hydrogen peroxide (H(2)O(2)) and from the host through the oxidative burst.

Deletion of a cation transporter promotes lysis in Streptococcus pneumoniae.

Streptococcus pneumoniae is a significant human pathogen which causes respiratory and serious invasive diseases. Mg(2+) is essential for life, and its concentration varies throughout the human body. Magnesium uptake plays an important role in the virulence of many bacterial pathogens.

Carbonic anhydrase is essential for Streptococcus pneumoniae growth in environmental ambient air.

The respiratory tract pathogen Streptococcus pneumoniae needs to adapt to the different levels of carbon dioxide (CO(2)) it encounters during transmission, colonization, and infection. Since CO(2) is important for various cellular processes, factors that allow optimal CO(2) sequestering are likely to be important for pneumococcal growth and survival. In this study, we showed that the putative pneumococcal carbonic anhydrase (PCA) is essential for in vitro growth of S.

Production of a class II two-component lantibiotic of Streptococcus pneumoniae using the class I nisin synthetic machinery and leader sequence.

Recent studies showed that the nisin modification machinery can successfully dehydrate serines and threonines and introduce lanthionine rings in small peptides that are fused to the nisin leader sequence. This opens up exciting possibilities to produce and engineer larger antimicrobial peptides in vivo. Here we demonstrate the exploitation of the class I nisin production machinery to generate, modify, and secrete biologically active, previously not-yet-isolated and -characterized class II two-component lantibiotics that have no sequence homology to nisin.

Generic and specific adaptive responses of Streptococcus pneumoniae to challenge with three distinct antimicrobial peptides, bacitracin, LL-37, and nisin.

To investigate the response of Streptococcus pneumoniae to three distinct antimicrobial peptides (AMPs), bacitracin, nisin, and LL-37, transcriptome analysis of challenged bacteria was performed. Only a limited number of genes were found to be up- or downregulated in all cases. Several of these common highly induced genes were chosen for further analysis, i.

Opposite effects of Mn2+ and Zn2+ on PsaR-mediated expression of the virulence genes pcpA, prtA, and psaBCA of Streptococcus pneumoniae.

Homeostasis of Zn(2+) and Mn(2+) is important for the physiology and virulence of the human pathogen Streptococcus pneumoniae. Here, transcriptome analysis was used to determine the response of S. pneumoniae D39 to a high concentration of Zn(2+).

The novel transcriptional regulator SczA mediates protection against Zn2+ stress by activation of the Zn2+-resistance gene czcD in Streptococcus pneumoniae.

Maintenance of the intracellular homeostasis of metal ions is important for the virulence of many bacterial pathogens. Here, we demonstrate that the czcD gene of the human pathogen Streptococcus pneumoniae is involved in resistance against Zn2+, and that its transcription is induced by the transition-metal ions Zn2+, Co2+ and Ni2+. Upstream of czcD a gene was identified, encoding a novel TetR family regulator, SczA, that is responsible for the metal ion-dependent activation of czcD expression.

Search for genes essential for pneumococcal transformation: the RADA DNA repair protein plays a role in genomic recombination of donor DNA.

We applied a novel negative selection strategy called genomic array footprinting (GAF) to identify genes required for genetic transformation of the gram-positive bacterium Streptococcus pneumoniae. Genome-wide mariner transposon mutant libraries in S. pneumoniae strain R6 were challenged by transformation with an antibiotic resistance cassette and growth in the presence of the corresponding antibiotic.

Development of genomic array footprinting for identification of conditionally essential genes in Streptococcus pneumoniae.

Streptococcus pneumoniae is a major cause of serious infections such as pneumonia and meningitis in both children and adults worldwide. Here, we describe the development of a high-throughput, genome-wide technique, genomic array footprinting (GAF), for the identification of genes essential for this bacterium at various stages during infection. GAF enables negative screens by means of a combination of transposon mutagenesis and microarray technology for the detection of transposon insertion sites.

BAGEL: a web-based bacteriocin genome mining tool.

A common problem in the annotation of open reading frames (ORFs) is the identification of genes that are functionally similar but have limited or no sequence homology. This is particularly the case for bacteriocins, a very diverse group of antimicrobial peptides produced by bacteria and usually encoded by small, poorly conserved ORFs. ORFs surrounding bacteriocin genes are often biosynthetic genes.

Regulation of glutamine and glutamate metabolism by GlnR and GlnA in Streptococcus pneumoniae.

Several genes involved in nitrogen metabolism are known to contribute to the virulence of pathogenic bacteria. Here, we studied the function of the nitrogen regulatory protein GlnR in the Gram-positive human pathogen Streptococcus pneumoniae. We demonstrate that GlnR mediates transcriptional repression of genes involved in glutamine synthesis and uptake (glnA and glnPQ), glutamate synthesis (gdhA), and the gene encoding the pentose phosphate pathway enzyme Zwf, which forms an operon with glnPQ.