Vitamin B6 inhibits activity of adenylosuccinate synthetase and growth of reference and clinical, antibiotic-resistant strains.

The current therapies against gastric pathogen are ineffective in over 20% of patients. Enzymes belonging to the purine salvage pathway are considered as novel drug targets in this pathogen. Therefore, the main aim of the current study was to determine the antibacterial activity of pyridoxal 5'-phosphate (PLP), an active form of vitamin B6, against reference and clinical strains of .

Interactions of 2,6-substituted purines with purine nucleoside phosphorylase from in solution and in the crystal, and the effects of these compounds on cell cultures of this bacterium.

represents a global health threat with around 50% of the world population infected. Due to the increasing number of antibiotic-resistant strains, new strategies for eradication of are needed. In this study, we suggest purine nucleoside phosphorylase (PNP) as a possible new drug target, by characterising its interactions with 2- and/or 6-substituted purines as well as the effect of these compounds on bacterial growth.

Interplay between DsbA1, DsbA2 and C8J_1298 Periplasmic Oxidoreductases of and Their Impact on Bacterial Physiology and Pathogenesis.

The bacterial proteins of the Dsb family catalyze the formation of disulfide bridges between cysteine residues that stabilize protein structures and ensure their proper functioning. Here, we report the detailed analysis of the Dsb pathway of . The oxidizing Dsb system of this pathogen is unique because it consists of two monomeric DsbAs (DsbA1 and DsbA2) and one dimeric bifunctional protein (C8J_1298).

A comprehensive method for determining cellular uptake of purine nucleoside phosphorylase and adenylosuccinate synthetase inhibitors by H. pylori.

Due to the growing number of Helicobacter pylori strains resistant to currently available antibiotics, there is an urgent need to design new drugs utilizing different molecular mechanisms than those that have been used up to now. Enzymes of the purine salvage pathway are possible targets of such new antibiotics because H. pylori is not able to synthetize purine nucleotides de novo.

C8J_1298, a bifunctional thiol oxidoreductase of Campylobacter jejuni, affects Dsb (disulfide bond) network functioning.

Posttranslational generation of disulfide bonds catalyzed by bacterial Dsb (disulfide bond) enzymes is essential for the oxidative folding of many proteins. Although we now have a good understanding of the Escherichia coli disulfide bond formation system, there are significant gaps in our knowledge concerning the Dsb systems of other bacteria, including Campylobacter jejuni, a food-borne, zoonotic pathogen. We attempted to gain a more complete understanding of the process by thorough analysis of C8J_1298 functioning in vitro and in vivo.

Engineering of the Dsb (disulfide bond) proteins - contribution towards understanding their mechanism of action and their applications in biotechnology and medicine.

The Dsb protein family in prokaryotes catalyzes the generation of disulfide bonds between thiol groups of cysteine residues in nascent proteins, ensuring their proper three-dimensional structure; these bonds are crucial for protein stability and function. The first Dsb protein, DsbA, was described in 1991. Since then, many details of the bond-formation process have been described through microbiological, biochemical, biophysical and bioinformatics strategies.

Bacterial thiol oxidoreductases - from basic research to new antibacterial strategies.

The recent, rapid increase in bacterial antimicrobial resistance has become a major public health concern. One approach to generate new classes of antibacterials is targeting virulence rather than the viability of bacteria. Proteins of the Dsb system, which play a key role in the virulence of many pathogenic microorganisms, represent potential new drug targets.

Helicobacter pylori HP0231 Influences Bacterial Virulence and Is Essential for Gastric Colonization.

The Dsb protein family is responsible for introducing disulfide bonds into nascent proteins in prokaryotes, stabilizing the structure of many proteins. Helicobacter pylori HP0231 is a Dsb-like protein, shown to catalyze disulfide bond formation and to participate in redox homeostasis. Notably, many H.

Lactic acid bacteria--20 years exploring their potential as live vectors for mucosal vaccination.

Lactic acid bacteria (LAB) are a diverse group of Gram-positive, nonsporulating, low G + C content bacteria. Many of them have been given generally regarded as safe status. Over the past two decades, intensive genetic and molecular research carried out on LAB, mainly Lactococcus lactis and some species of the Lactobacillus genus, has revealed new, potential biomedical LAB applications, including the use of LAB as adjuvants, immunostimulators, or therapeutic drug delivery systems, or as factories to produce therapeutic molecules.

Lactic acid bacteria as a surface display platform for Campylobacter jejuni antigens.

Background: Food poisoning and diarrheal diseases continue to pose serious health care and socioeconomic problems worldwide. Campylobacter spp. is a very widespread cause of gastroenteritis.

Evaluation of the immunogenicity of Campylobacter jejuni CjaA protein delivered by Salmonella enterica sv. Typhimurium strain with regulated delayed attenuation in chickens.

Campylobacter spp. are regarded as the most common bacterial cause of gastroenteritis worldwide, and consumption of chicken meat contaminated by Campylobacter is considered to be one of the most frequent sources of human infection in developed countries. Here we evaluated the immunogenicity and protective efficacy of Salmonella Typhimurium χ9718 producing the Campylobacter jejuni CjaA protein as a chicken anti-Campylobacter vaccine.

[Application of microorganisms as delivery vehicles in cancer gene therapies].

Gene therapy represents a potential new strategy for cancer treatment. In order to deliver a transgene into target tumor cells, a vector system is required. To date, most of the cancer therapies are based on the use of different viral vectors.

Peptidoglycan-associated lipoprotein (Pal) of Gram-negative bacteria: function, structure, role in pathogenesis and potential application in immunoprophylaxis.

The protein Pal (peptidoglycan-associated lipoprotein) is anchored in the outer membrane (OM) of Gram-negative bacteria and interacts with Tol proteins. Tol-Pal proteins form two complexes: the first is composed of three inner membrane Tol proteins (TolA, TolQ and TolR); the second consists of the TolB and Pal proteins linked to the cell's OM. These complexes interact with one another forming a multiprotein membrane-spanning system.

Proteomic technology in the design of new effective antibacterial vaccines.

Infectious diseases still remain the main cause of human premature deaths, especially in developing countries. Vaccines constitute the most cost-effective tool for prophylaxis of infectious diseases. Elucidation of the complete genomes of many bacterial pathogens has provided a new blueprint for the search of novel vaccine candidates.

Update on Campylobacter jejuni vaccine development for preventing human campylobacteriosis.

Campylobacteriosis constitutes a serious medical and socioeconomic problem worldwide. Rapidly increasing antibiotic resistance of bacterial strains compels us to develop alternative therapeutic strategies and to search for efficient immunoprophylactic methods. The vast majority of Campylobacter infections in developed countries occur as sporadic cases, mainly caused by eating undercooked Campylobacter-contaminated poultry.

[Immunoproteomics of Helicobacter pylori--strategy for improvement of diagnostic tests and vaccine development].

Helicobacter pylori, Gram-negative spiral-shaped bacteria, member of epsilon-Proteobacteria, colonizes the gastric mucosa of humans. H. pylori has been identified as the causative agent of chronic inflammation, chronic gastritis and peptic ulceration and is considered a risk factor for the development of mucosa-associated lymphoid tissue lymphoma and adenocarcinoma of the stomach.

[Influence of human gastrointestinal tract bacterial pathogens on host cell apoptosis].

Several pathogenic bacteria are able to trigger apoptosis in the host cell, but the mechanisms by which it occurs differ, and the resulting pathology can take different courses. Induction and/or blockage of programmed cell death upon infection is a result of complex interaction of bacterial proteins with cellular proteins involved in signal transduction and apoptosis. In this review we focus on pro/anti-apoptotic activities exhibited by two enteric pathogens Salmonella enterica, Yersinia spp.

Oral immunization of chickens with avirulent Salmonella vaccine strain carrying C. jejuni 72Dz/92 cjaA gene elicits specific humoral immune response associated with protection against challenge with wild-type Campylobacter.

It is well documented that poultry and poultry products are the major source of human campylobacteriosis and salmonellosis. This study examined the general efficacy of avirulent Salmonella vaccine strains expressing Campylobacter antigen as a bivalent chicken vaccine prototype. Three C.